Adapt to new shrinker API #8

bergwolf · 2013-06-05T10:13:17Z

The patchset adapts Lustre shrinker implementation to new count/scan shrinker API.

The count/scan shrinker is still under review but is likely to be merged in next merge window. So we'd better prepare for it to avoid breaking build when Lustre is merged in the same merge window.

Peng Tao (4):
staging/lustre/ldlm: convert to shrinkers to count/scan API
staging/lustre/obdclass: convert lu_object shrinker to count/scan API
staging/lustre/ptlrpc: convert to new shrinker API
staging/lustre/libcfs: cleanup linux-mem.h

.../lustre/include/linux/libcfs/linux/linux-mem.h | 38 ------
drivers/staging/lustre/lustre/ldlm/ldlm_pool.c | 133 +++++++++++---------
drivers/staging/lustre/lustre/obdclass/lu_object.c | 96 ++++++++-------
drivers/staging/lustre/lustre/ptlrpc/sec_bulk.c | 74 ++++++-----
4 files changed, 161 insertions(+), 180 deletions(-)

convert ldlm shrinker to new count/scan API. Signed-off-by: Peng Tao <tao.peng@emc.com>

convert lu_object shrinker to new count/scan API. Signed-off-by: Peng Tao <tao.peng@emc.com>

Convert sptlrpc encode pool shrinker to use scan/count API. Signed-off-by: Peng Tao <tao.peng@emc.com>

remove shrinker related wrappers. Signed-off-by: Peng Tao <tao.peng@emc.com>

Daniel Petre reported crashes in icmp_dst_unreach() with following call graph: #3 [ffff88003fc03938] __stack_chk_fail at ffffffff81037f77 #4 [ffff88003fc03948] icmp_send at ffffffff814d5fec #5 [ffff88003fc03ae8] ipv4_link_failure at ffffffff814a1795 #6 [ffff88003fc03af8] ipgre_tunnel_xmit at ffffffff814e7965 #7 [ffff88003fc03b78] dev_hard_start_xmit at ffffffff8146e032 #8 [ffff88003fc03bc8] sch_direct_xmit at ffffffff81487d66 #9 [ffff88003fc03c08] __qdisc_run at ffffffff81487efd #10 [ffff88003fc03c48] dev_queue_xmit at ffffffff8146e5a7 #11 [ffff88003fc03c88] ip_finish_output at ffffffff814ab596 Daniel found a similar problem mentioned in http://lkml.indiana.edu/hypermail/linux/kernel/1007.0/00961.html And indeed this is the root cause : skb->cb[] contains data fooling IP stack. We must clear IPCB in ip_tunnel_xmit() sooner in case dst_link_failure() is called. Or else skb->cb[] might contain garbage from GSO segmentation layer. A similar fix was tested on linux-3.9, but gre code was refactored in linux-3.10. I'll send patches for stable kernels as well. Many thanks to Daniel for providing reports, patches and testing ! Reported-by: Daniel Petre <daniel.petre@rcs-rds.ro> Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>

…rnel/git/dhowells/linux-fs Pull FS-Cache updates from David Howells: "This contains a number of fixes for various FS-Cache issues plus some cleanups. The commits are, in order: 1) Provide a system wait_on_atomic_t() and wake_up_atomic_t() sharing the bit-wait table (enhancement for #8). 2) Don't put spin_lock() in a while-condition as spin_lock() may have a do {} while(0) wrapper (cleanup). 3) Symbolically name i_mutex lock classes rather than using numbers in CacheFiles (cleanup). 4) Don't sleep in page release if __GFP_FS is not set (deadlock vs ext4). 5) Uninline fscache_object_init() (cleanup for #7). 6) Wrap checks on object state (cleanup for #7). 7) Simplify the object state machine by separating work states from wait states. 8) Simplify cookie retention by objects (NULL pointer deref fix). 9) Remove unused list_to_page() macro (cleanup). 10) Make the remaining-pages counter in the retrieval op atomic (assertion failure fix). 11) Don't use spin_is_locked() in assertions (assertion failure fix)" * tag 'fscache-20130702' of git://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-fs: FS-Cache: Don't use spin_is_locked() in assertions FS-Cache: The retrieval remaining-pages counter needs to be atomic_t cachefiles: remove unused macro list_to_page() FS-Cache: Simplify cookie retention for fscache_objects, fixing oops FS-Cache: Fix object state machine to have separate work and wait states FS-Cache: Wrap checks on object state FS-Cache: Uninline fscache_object_init() FS-Cache: Don't sleep in page release if __GFP_FS is not set CacheFiles: name i_mutex lock class explicitly fs/fscache: remove spin_lock() from the condition in while() Add wait_on_atomic_t() and wake_up_atomic_t()

Several people reported the warning: "kernel BUG at kernel/timer.c:729!" and the stack trace is: #7 [ffff880214d25c10] mod_timer+501 at ffffffff8106d905 #8 [ffff880214d25c50] br_multicast_del_pg.isra.20+261 at ffffffffa0731d25 [bridge] #9 [ffff880214d25c80] br_multicast_disable_port+88 at ffffffffa0732948 [bridge] #10 [ffff880214d25cb0] br_stp_disable_port+154 at ffffffffa072bcca [bridge] #11 [ffff880214d25ce8] br_device_event+520 at ffffffffa072a4e8 [bridge] #12 [ffff880214d25d18] notifier_call_chain+76 at ffffffff8164aafc #13 [ffff880214d25d50] raw_notifier_call_chain+22 at ffffffff810858f6 #14 [ffff880214d25d60] call_netdevice_notifiers+45 at ffffffff81536aad #15 [ffff880214d25d80] dev_close_many+183 at ffffffff81536d17 #16 [ffff880214d25dc0] rollback_registered_many+168 at ffffffff81537f68 #17 [ffff880214d25de8] rollback_registered+49 at ffffffff81538101 #18 [ffff880214d25e10] unregister_netdevice_queue+72 at ffffffff815390d8 #19 [ffff880214d25e30] __tun_detach+272 at ffffffffa074c2f0 [tun] #20 [ffff880214d25e88] tun_chr_close+45 at ffffffffa074c4bd [tun] #21 [ffff880214d25ea8] __fput+225 at ffffffff8119b1f1 #22 [ffff880214d25ef0] ____fput+14 at ffffffff8119b3fe #23 [ffff880214d25f00] task_work_run+159 at ffffffff8107cf7f #24 [ffff880214d25f30] do_notify_resume+97 at ffffffff810139e1 #25 [ffff880214d25f50] int_signal+18 at ffffffff8164f292 this is due to I forgot to check if mp->timer is armed in br_multicast_del_pg(). This bug is introduced by commit 9f00b2e (bridge: only expire the mdb entry when query is received). Same for __br_mdb_del(). Tested-by: poma <pomidorabelisima@gmail.com> Reported-by: LiYonghua <809674045@qq.com> Reported-by: Robert Hancock <hancockrwd@gmail.com> Cc: Herbert Xu <herbert@gondor.apana.org.au> Cc: Stephen Hemminger <stephen@networkplumber.org> Cc: "David S. Miller" <davem@davemloft.net> Signed-off-by: Cong Wang <amwang@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>

…ifier In fd4363f ("x86: Introduce int3 (breakpoint)-based instruction patching"), the mechanism that was introduced for notifying alternatives code from int3 exception handler that and exception occured was die_notifier. This is however problematic, as early code might be using jump labels even before the notifier registration has been performed, which will then lead to an oops due to unhandled exception. One of such occurences has been encountered by Fengguang: int3: 0000 [#1] PREEMPT SMP DEBUG_PAGEALLOC Modules linked in: CPU: 1 PID: 0 Comm: swapper/1 Not tainted 3.11.0-rc1-01429-g04bf576 #8 task: ffff88000da1b040 ti: ffff88000da1c000 task.ti: ffff88000da1c000 RIP: 0010:[<ffffffff811098cc>] [<ffffffff811098cc>] ttwu_do_wakeup+0x28/0x225 RSP: 0000:ffff88000dd03f10 EFLAGS: 00000006 RAX: 0000000000000000 RBX: ffff88000dd12940 RCX: ffffffff81769c40 RDX: 0000000000000002 RSI: 0000000000000000 RDI: 0000000000000001 RBP: ffff88000dd03f28 R08: ffffffff8176a8c0 R09: 0000000000000002 R10: ffffffff810ff484 R11: ffff88000dd129e8 R12: ffff88000dbc90c0 R13: ffff88000dbc90c0 R14: ffff88000da1dfd8 R15: ffff88000da1dfd8 FS: 0000000000000000(0000) GS:ffff88000dd00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 000000008005003b CR2: 00000000ffffffff CR3: 0000000001c88000 CR4: 00000000000006e0 Stack: ffff88000dd12940 ffff88000dbc90c0 ffff88000da1dfd8 ffff88000dd03f48 ffffffff81109e2b ffff88000dd12940 0000000000000000 ffff88000dd03f68 ffffffff81109e9e 0000000000000000 0000000000012940 ffff88000dd03f98 Call Trace: <IRQ> [<ffffffff81109e2b>] ttwu_do_activate.constprop.56+0x6d/0x79 [<ffffffff81109e9e>] sched_ttwu_pending+0x67/0x84 [<ffffffff8110c845>] scheduler_ipi+0x15a/0x2b0 [<ffffffff8104dfb4>] smp_reschedule_interrupt+0x38/0x41 [<ffffffff8173bf5d>] reschedule_interrupt+0x6d/0x80 <EOI> [<ffffffff810ff484>] ? __atomic_notifier_call_chain+0x5/0xc1 [<ffffffff8105cc30>] ? native_safe_halt+0xd/0x16 [<ffffffff81015f10>] default_idle+0x147/0x282 [<ffffffff81017026>] arch_cpu_idle+0x3d/0x5d [<ffffffff81127d6a>] cpu_idle_loop+0x46d/0x5db [<ffffffff81127f5c>] cpu_startup_entry+0x84/0x84 [<ffffffff8104f4f8>] start_secondary+0x3c8/0x3d5 [...] Fix this by directly calling poke_int3_handler() from the int3 exception handler (analogically to what ftrace has been doing already), instead of relying on notifier, registration of which might not have yet been finalized by the time of the first trap. Reported-and-tested-by: Fengguang Wu <fengguang.wu@intel.com> Signed-off-by: Jiri Kosina <jkosina@suse.cz> Acked-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> Cc: H. Peter Anvin <hpa@linux.intel.com> Cc: Fengguang Wu <fengguang.wu@intel.com> Cc: Steven Rostedt <rostedt@goodmis.org> Link: http://lkml.kernel.org/r/alpine.LNX.2.00.1307231007490.14024@pobox.suse.cz Signed-off-by: Ingo Molnar <mingo@kernel.org>

We used to keep the port's char device structs and the /sys entries around till the last reference to the port was dropped. This is actually unnecessary, and resulted in buggy behaviour: 1. Open port in guest 2. Hot-unplug port 3. Hot-plug a port with the same 'name' property as the unplugged one This resulted in hot-plug being unsuccessful, as a port with the same name already exists (even though it was unplugged). This behaviour resulted in a warning message like this one: -------------------8<--------------------------------------- WARNING: at fs/sysfs/dir.c:512 sysfs_add_one+0xc9/0x130() (Not tainted) Hardware name: KVM sysfs: cannot create duplicate filename '/devices/pci0000:00/0000:00:04.0/virtio0/virtio-ports/vport0p1' Call Trace: [<ffffffff8106b607>] ? warn_slowpath_common+0x87/0xc0 [<ffffffff8106b6f6>] ? warn_slowpath_fmt+0x46/0x50 [<ffffffff811f2319>] ? sysfs_add_one+0xc9/0x130 [<ffffffff811f23e8>] ? create_dir+0x68/0xb0 [<ffffffff811f2469>] ? sysfs_create_dir+0x39/0x50 [<ffffffff81273129>] ? kobject_add_internal+0xb9/0x260 [<ffffffff812733d8>] ? kobject_add_varg+0x38/0x60 [<ffffffff812734b4>] ? kobject_add+0x44/0x70 [<ffffffff81349de4>] ? get_device_parent+0xf4/0x1d0 [<ffffffff8134b389>] ? device_add+0xc9/0x650 -------------------8<--------------------------------------- Instead of relying on guest applications to release all references to the ports, we should go ahead and unregister the port from all the core layers. Any open/read calls on the port will then just return errors, and an unplug/plug operation on the host will succeed as expected. This also caused buggy behaviour in case of the device removal (not just a port): when the device was removed (which means all ports on that device are removed automatically as well), the ports with active users would clean up only when the last references were dropped -- and it would be too late then to be referencing char device pointers, resulting in oopses: -------------------8<--------------------------------------- PID: 6162 TASK: ffff8801147ad500 CPU: 0 COMMAND: "cat" #0 [ffff88011b9d5a90] machine_kexec at ffffffff8103232b #1 [ffff88011b9d5af0] crash_kexec at ffffffff810b9322 #2 [ffff88011b9d5bc0] oops_end at ffffffff814f4a50 #3 [ffff88011b9d5bf0] die at ffffffff8100f26b #4 [ffff88011b9d5c20] do_general_protection at ffffffff814f45e2 #5 [ffff88011b9d5c50] general_protection at ffffffff814f3db5 [exception RIP: strlen+2] RIP: ffffffff81272ae2 RSP: ffff88011b9d5d00 RFLAGS: 00010246 RAX: 0000000000000000 RBX: ffff880118901c18 RCX: 0000000000000000 RDX: ffff88011799982c RSI: 00000000000000d0 RDI: 3a303030302f3030 RBP: ffff88011b9d5d38 R8: 0000000000000006 R9: ffffffffa0134500 R10: 0000000000001000 R11: 0000000000001000 R12: ffff880117a1cc10 R13: 00000000000000d0 R14: 0000000000000017 R15: ffffffff81aff700 ORIG_RAX: ffffffffffffffff CS: 0010 SS: 0018 #6 [ffff88011b9d5d00] kobject_get_path at ffffffff8126dc5d #7 [ffff88011b9d5d40] kobject_uevent_env at ffffffff8126e551 #8 [ffff88011b9d5dd0] kobject_uevent at ffffffff8126e9eb #9 [ffff88011b9d5de0] device_del at ffffffff813440c7 -------------------8<--------------------------------------- So clean up when we have all the context, and all that's left to do when the references to the port have dropped is to free up the port struct itself. CC: <stable@vger.kernel.org> Reported-by: chayang <chayang@redhat.com> Reported-by: YOGANANTH SUBRAMANIAN <anantyog@in.ibm.com> Reported-by: FuXiangChun <xfu@redhat.com> Reported-by: Qunfang Zhang <qzhang@redhat.com> Reported-by: Sibiao Luo <sluo@redhat.com> Signed-off-by: Amit Shah <amit.shah@redhat.com> Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>

In several places, this snippet is used when removing neigh entries: list_del(&neigh->list); ipoib_neigh_free(neigh); The list_del() removes neigh from the associated struct ipoib_path, while ipoib_neigh_free() removes neigh from the device's neigh entry lookup table. Both of these operations are protected by the priv->lock spinlock. The table however is also protected via RCU, and so naturally the lock is not held when doing reads. This leads to a race condition, in which a thread may successfully look up a neigh entry that has already been deleted from neigh->list. Since the previous deletion will have marked the entry with poison, a second list_del() on the object will cause a panic: #5 [ffff8802338c3c70] general_protection at ffffffff815108c5 [exception RIP: list_del+16] RIP: ffffffff81289020 RSP: ffff8802338c3d20 RFLAGS: 00010082 RAX: dead000000200200 RBX: ffff880433e60c88 RCX: 0000000000009e6c RDX: 0000000000000246 RSI: ffff8806012ca298 RDI: ffff880433e60c88 RBP: ffff8802338c3d30 R8: ffff8806012ca2e8 R9: 00000000ffffffff R10: 0000000000000001 R11: 0000000000000000 R12: ffff8804346b2020 R13: ffff88032a3e7540 R14: ffff8804346b26e0 R15: 0000000000000246 ORIG_RAX: ffffffffffffffff CS: 0010 SS: 0000 #6 [ffff8802338c3d38] ipoib_cm_tx_handler at ffffffffa066fe0a [ib_ipoib] #7 [ffff8802338c3d98] cm_process_work at ffffffffa05149a7 [ib_cm] #8 [ffff8802338c3de8] cm_work_handler at ffffffffa05161aa [ib_cm] #9 [ffff8802338c3e38] worker_thread at ffffffff81090e10 #10 [ffff8802338c3ee8] kthread at ffffffff81096c66 #11 [ffff8802338c3f48] kernel_thread at ffffffff8100c0ca We move the list_del() into ipoib_neigh_free(), so that deletion happens only once, after the entry has been successfully removed from the lookup table. This same behavior is already used in ipoib_del_neighs_by_gid() and __ipoib_reap_neigh(). Signed-off-by: Jim Foraker <foraker1@llnl.gov> Reviewed-by: Or Gerlitz <ogerlitz@mellanox.com> Reviewed-by: Jack Wang <jinpu.wang@profitbricks.com> Reviewed-by: Shlomo Pongratz <shlomop@mellanox.com> Signed-off-by: Roland Dreier <roland@purestorage.com>

When 2 devices are registered at the same time, in Part 2 both will get the same minor number, making Part6 crash, because it cannot create a create a device with a duplicated minor: [ 7.157648] ------------[ cut here ]------------ [ 7.157666] WARNING: at fs/sysfs/dir.c:530 sysfs_add_one+0xbd/0xe0() [ 7.157669] sysfs: cannot create duplicate filename '/dev/char/81:1' [ 7.157672] Modules linked in: qtec_xform(+) qt5023_video(+) videobuf2_vmalloc videobuf2_dma_sg videobuf2_memops videobuf2_core gpio_xilinx(+) qtec_white qtec_cmosis(+) qtec_pcie qt5023 [ 7.157694] CPU: 0 PID: 120 Comm: systemd-udevd Not tainted 3.10.0-qtec-standard #8 [ 7.157698] Hardware name: QTechnology QT5022/QT5022, BIOS PM_2.1.0.309 X64 05/23/2013 [ 7.157702] 0000000000000009 ffff8801788358e8 ffffffff8176c487 ffff880178835928 [ 7.157707] ffffffff8106f6f0 ffff880175759770 00000000ffffffef ffff880175759930 [ 7.157712] ffff8801788359e8 ffff880178bff000 ffff880175759930 ffff880178835988 [ 7.157718] Call Trace: [ 7.157728] [<ffffffff8176c487>] dump_stack+0x19/0x1b [ 7.157735] [<ffffffff8106f6f0>] warn_slowpath_common+0x70/0xa0 [ 7.157740] [<ffffffff8106f7d6>] warn_slowpath_fmt+0x46/0x50 [ 7.157746] [<ffffffff81324b35>] ? strlcat+0x65/0x90 [ 7.157750] [<ffffffff811d516d>] sysfs_add_one+0xbd/0xe0 [ 7.157755] [<ffffffff811d5c6b>] sysfs_do_create_link_sd+0xdb/0x200 [ 7.157760] [<ffffffff811d5db1>] sysfs_create_link+0x21/0x40 [ 7.157765] [<ffffffff813e277b>] device_add+0x21b/0x6d0 [ 7.157772] [<ffffffff813f2985>] ? pm_runtime_init+0xe5/0xf0 [ 7.157776] [<ffffffff813e2c4e>] device_register+0x1e/0x30 [ 7.157782] [<ffffffff8153e8c3>] __video_register_device+0x313/0x610 [ 7.157791] [<ffffffffa00957c5>] qtec_xform_probe+0x465/0x7a4 [qtec_xform] [ 7.157797] [<ffffffff813e7b13>] platform_drv_probe+0x43/0x80 [ 7.157802] [<ffffffff813e531a>] ? driver_sysfs_add+0x7a/0xb0 [ 7.157807] [<ffffffff813e584b>] driver_probe_device+0x8b/0x3a0 [ 7.157812] [<ffffffff813e5c0b>] __driver_attach+0xab/0xb0 [ 7.157816] [<ffffffff813e5b60>] ? driver_probe_device+0x3a0/0x3a0 [ 7.157820] [<ffffffff813e37fd>] bus_for_each_dev+0x5d/0xa0 [ 7.157825] [<ffffffff813e529e>] driver_attach+0x1e/0x20 [ 7.157829] [<ffffffff813e4d3e>] bus_add_driver+0x10e/0x280 [ 7.157833] [<ffffffffa0099000>] ? 0xffffffffa0098fff [ 7.157837] [<ffffffffa0099000>] ? 0xffffffffa0098fff [ 7.157842] [<ffffffff813e6317>] driver_register+0x77/0x170 [ 7.157848] [<ffffffff81151bcc>] ? __vunmap+0x9c/0x110 [ 7.157852] [<ffffffffa0099000>] ? 0xffffffffa0098fff [ 7.157857] [<ffffffff813e7236>] platform_driver_register+0x46/0x50 [ 7.157863] [<ffffffffa0099010>] qtec_xform_plat_driver_init+0x10/0x12 [qtec_xform] [ 7.157869] [<ffffffff810002ea>] do_one_initcall+0xea/0x1a0 [ 7.157875] [<ffffffff810cf1f1>] load_module+0x1a91/0x2630 [ 7.157880] [<ffffffff8133bee0>] ? ddebug_proc_show+0xe0/0xe0 [ 7.157887] [<ffffffff817760f2>] ? page_fault+0x22/0x30 [ 7.157892] [<ffffffff810cfe7a>] SyS_init_module+0xea/0x140 [ 7.157898] [<ffffffff8177e5b9>] tracesys+0xd0/0xd5 [ 7.157902] ---[ end trace 660cc3a65a4bf01b ]--- [ 7.157939] __video_register_device: device_register failed Signed-off-by: Ricardo Ribalda Delgado <ricardo.ribalda@gmail.com> Acked-by: Sakari Ailus <sakari.ailus@iki.fi> Acked-by: Hans Verkuil <hans.verkuil@cisco.com> Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com> Signed-off-by: Mauro Carvalho Chehab <m.chehab@samsung.com>

When booting secondary CPUs, announce_cpu() is called to show which cpu has been brought up. For example: [ 0.402751] smpboot: Booting Node 0, Processors #1 #2 #3 #4 #5 OK [ 0.525667] smpboot: Booting Node 1, Processors #6 #7 #8 #9 #10 #11 OK [ 0.755592] smpboot: Booting Node 0, Processors #12 #13 #14 #15 #16 #17 OK [ 0.890495] smpboot: Booting Node 1, Processors #18 #19 #20 #21 #22 #23 But the last "OK" is lost, because 'nr_cpu_ids-1' represents the maximum possible cpu id. It should use the maximum present cpu id in case not all CPUs booted up. Signed-off-by: Libin <huawei.libin@huawei.com> Cc: <guohanjun@huawei.com> Cc: <wangyijing@huawei.com> Cc: <fenghua.yu@intel.com> Cc: <paul.gortmaker@windriver.com> Link: http://lkml.kernel.org/r/1378378676-18276-1-git-send-email-huawei.libin@huawei.com [ tweaked the changelog, removed unnecessary line break, tweaked the format to align the fields vertically. ] Signed-off-by: Ingo Molnar <mingo@kernel.org>

Enable only those interrupts that we can handle & acknowledge in the interrupt handler. At least on EdgeRouter Lite, the hardware may occasionally interrupt with some error condition when the physical link status changes frequently. Since the interrupt condition is not acked properly, this leads to the following warning and the IRQ gets disabled completely: [ 41.324700] eth0: Link down [ 44.324721] eth0: 1000 Mbps Full duplex, port 0, queue 0 [ 44.885590] irq 117: nobody cared (try booting with the "irqpoll" option) [ 44.892397] CPU: 0 PID: 0 Comm: swapper/0 Not tainted 3.11.0-rc5-edge-los.git-27d042f-dirty-00950-gaa42f2d-dirty #8 [ 44.902825] Stack : ffffffff815c0000 0000000000000004 0000000000000003 0000000000000000 ffffffff81fd0000 ffffffff815c0000 0000000000000004 ffffffff8118530c ffffffff815c0000 ffffffff811858d8 0000000000000000 0000000000000000 ffffffff81fd0000 ffffffff81fc0000 ffffffff8152f3a0 ffffffff815b7bf7 ffffffff81fc6688 ffffffff815b8060 0000000000000000 0000000000000000 0000000000000000 ffffffff815346c8 ffffffff815346b0 ffffffff814a6a18 ffffffff8158b848 ffffffff81145614 ffffffff81593800 ffffffff81187174 ffffffff815b7d00 ffffffff8158b760 0000000000000000 ffffffff814a9184 0000000000000000 0000000000000000 0000000000000000 0000000000000000 0000000000000000 ffffffff811203b8 0000000000000000 0000000000000000 ... [ 44.968408] Call Trace: [ 44.970873] [<ffffffff811203b8>] show_stack+0x68/0x80 [ 44.975937] [<ffffffff814a9184>] dump_stack+0x78/0xb8 [ 44.980999] [<ffffffff811aac54>] __report_bad_irq+0x44/0x108 [ 44.986662] [<ffffffff811ab238>] note_interrupt+0x248/0x2a0 [ 44.992240] [<ffffffff811a85e4>] handle_irq_event_percpu+0x144/0x200 [ 44.998598] [<ffffffff811a86f4>] handle_irq_event+0x54/0x90 [ 45.004176] [<ffffffff811ab908>] handle_level_irq+0xd0/0x148 [ 45.009839] [<ffffffff811a7b04>] generic_handle_irq+0x34/0x50 [ 45.015589] [<ffffffff8111dae8>] do_IRQ+0x18/0x30 [ 45.020301] [<ffffffff8110486c>] plat_irq_dispatch+0x74/0xb8 [ 45.025958] [ 45.027451] handlers: [ 45.029731] [<ffffffff813fca10>] cvm_oct_rgmii_rml_interrupt [ 45.035397] Disabling IRQ #117 [ 45.038742] Port 0 receive error code 13, packet dropped [ 46.324719] eth0: Link down [ 48.324733] eth0: 1000 Mbps Full duplex, port 0, queue 0 Reported-by: "Jason A. Donenfeld" <Jason@zx2c4.com> Signed-off-by: Aaro Koskinen <aaro.koskinen@iki.fi> Acked-by: David Daney <david.daney@cavium.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: devel@driverdev.osuosl.org Cc: linux-mips@linux-mips.org Cc: Jason A. Donenfeld <Jason@zx2c4.com> Cc: richard@nod.at Patchwork: https://patchwork.linux-mips.org/patch/5810/ Signed-off-by: Ralf Baechle <ralf@linux-mips.org>

Enable only those interrupts that we can handle & acknowledge in the interrupt handler. At least on EdgeRouter Lite, the hardware may occasionally interrupt with some error condition when the physical link status changes frequently. Since the interrupt condition is not acked properly, this leads to the following warning and the IRQ gets disabled completely: [ 41.324700] eth0: Link down [ 44.324721] eth0: 1000 Mbps Full duplex, port 0, queue 0 [ 44.885590] irq 117: nobody cared (try booting with the "irqpoll" option) [ 44.892397] CPU: 0 PID: 0 Comm: swapper/0 Not tainted 3.11.0-rc5-edge-los.git-27d042f-dirty-00950-gaa42f2d-dirty #8 [ 44.902825] Stack : ffffffff815c0000 0000000000000004 0000000000000003 0000000000000000 ffffffff81fd0000 ffffffff815c0000 0000000000000004 ffffffff8118530c ffffffff815c0000 ffffffff811858d8 0000000000000000 0000000000000000 ffffffff81fd0000 ffffffff81fc0000 ffffffff8152f3a0 ffffffff815b7bf7 ffffffff81fc6688 ffffffff815b8060 0000000000000000 0000000000000000 0000000000000000 ffffffff815346c8 ffffffff815346b0 ffffffff814a6a18 ffffffff8158b848 ffffffff81145614 ffffffff81593800 ffffffff81187174 ffffffff815b7d00 ffffffff8158b760 0000000000000000 ffffffff814a9184 0000000000000000 0000000000000000 0000000000000000 0000000000000000 0000000000000000 ffffffff811203b8 0000000000000000 0000000000000000 ... [ 44.968408] Call Trace: [ 44.970873] [<ffffffff811203b8>] show_stack+0x68/0x80 [ 44.975937] [<ffffffff814a9184>] dump_stack+0x78/0xb8 [ 44.980999] [<ffffffff811aac54>] __report_bad_irq+0x44/0x108 [ 44.986662] [<ffffffff811ab238>] note_interrupt+0x248/0x2a0 [ 44.992240] [<ffffffff811a85e4>] handle_irq_event_percpu+0x144/0x200 [ 44.998598] [<ffffffff811a86f4>] handle_irq_event+0x54/0x90 [ 45.004176] [<ffffffff811ab908>] handle_level_irq+0xd0/0x148 [ 45.009839] [<ffffffff811a7b04>] generic_handle_irq+0x34/0x50 [ 45.015589] [<ffffffff8111dae8>] do_IRQ+0x18/0x30 [ 45.020301] [<ffffffff8110486c>] plat_irq_dispatch+0x74/0xb8 [ 45.025958] [ 45.027451] handlers: [ 45.029731] [<ffffffff813fca10>] cvm_oct_rgmii_rml_interrupt [ 45.035397] Disabling IRQ #117 [ 45.038742] Port 0 receive error code 13, packet dropped [ 46.324719] eth0: Link down [ 48.324733] eth0: 1000 Mbps Full duplex, port 0, queue 0 Reported-by: "Jason A. Donenfeld" <Jason@zx2c4.com> Signed-off-by: Aaro Koskinen <aaro.koskinen@iki.fi> Acked-by: David Daney <david.daney@cavium.com> Acked-by: Jason A. Donenfeld <Jason@zx2c4.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

When parsing lines from objdump a line containing source code starting with a numeric label is mistaken for a line of disassembly starting with a memory address. Current validation fails to recognise that the "memory address" is out of range and calculates an invalid offset which later causes this segfault: Program received signal SIGSEGV, Segmentation fault. 0x0000000000457315 in disasm__calc_percent (notes=0xc98970, evidx=0, offset=143705, end=2127526177, path=0x7fffffffbf50) at util/annotate.c:631 631 hits += h->addr[offset++]; (gdb) bt #0 0x0000000000457315 in disasm__calc_percent (notes=0xc98970, evidx=0, offset=143705, end=2127526177, path=0x7fffffffbf50) at util/annotate.c:631 #1 0x00000000004d65e3 in annotate_browser__calc_percent (browser=0x7fffffffd130, evsel=0xa01da0) at ui/browsers/annotate.c:364 #2 0x00000000004d7433 in annotate_browser__run (browser=0x7fffffffd130, evsel=0xa01da0, hbt=0x0) at ui/browsers/annotate.c:672 #3 0x00000000004d80c9 in symbol__tui_annotate (sym=0xc989a0, map=0xa02660, evsel=0xa01da0, hbt=0x0) at ui/browsers/annotate.c:962 #4 0x00000000004d7aa0 in hist_entry__tui_annotate (he=0xdf73f0, evsel=0xa01da0, hbt=0x0) at ui/browsers/annotate.c:823 #5 0x00000000004dd648 in perf_evsel__hists_browse (evsel=0xa01da0, nr_events=1, helpline= 0x58b768 "For a higher level overview, try: perf report --sort comm,dso", ev_name=0xa02cd0 "cycles", left_exits=false, hbt= 0x0, min_pcnt=0, env=0xa011e0) at ui/browsers/hists.c:1659 #6 0x00000000004de372 in perf_evlist__tui_browse_hists (evlist=0xa01520, help= 0x58b768 "For a higher level overview, try: perf report --sort comm,dso", hbt=0x0, min_pcnt=0, env=0xa011e0) at ui/browsers/hists.c:1950 #7 0x000000000042cf6b in __cmd_report (rep=0x7fffffffd6c0) at builtin-report.c:581 #8 0x000000000042e25d in cmd_report (argc=0, argv=0x7fffffffe4b0, prefix=0x0) at builtin-report.c:965 #9 0x000000000041a0e1 in run_builtin (p=0x801548, argc=1, argv=0x7fffffffe4b0) at perf.c:319 #10 0x000000000041a319 in handle_internal_command (argc=1, argv=0x7fffffffe4b0) at perf.c:376 #11 0x000000000041a465 in run_argv (argcp=0x7fffffffe38c, argv=0x7fffffffe380) at perf.c:420 #12 0x000000000041a707 in main (argc=1, argv=0x7fffffffe4b0) at perf.c:521 After the fix is applied the symbol can be annotated showing the problematic line "1: rep" copy_user_generic_string /usr/lib/debug/lib/modules/3.9.10-100.fc17.x86_64/vmlinux */ ENTRY(copy_user_generic_string) CFI_STARTPROC ASM_STAC andl %edx,%edx and %edx,%edx jz 4f je 37 cmpl $8,%edx cmp $0x8,%edx jb 2f /* less than 8 bytes, go to byte copy loop */ jb 33 ALIGN_DESTINATION mov %edi,%ecx and $0x7,%ecx je 28 sub $0x8,%ecx neg %ecx sub %ecx,%edx 1a: mov (%rsi),%al mov %al,(%rdi) inc %rsi inc %rdi dec %ecx jne 1a movl %edx,%ecx 28: mov %edx,%ecx shrl $3,%ecx shr $0x3,%ecx andl $7,%edx and $0x7,%edx 1: rep 100.00 rep movsq %ds:(%rsi),%es:(%rdi) movsq 2: movl %edx,%ecx 33: mov %edx,%ecx 3: rep rep movsb %ds:(%rsi),%es:(%rdi) movsb 4: xorl %eax,%eax 37: xor %eax,%eax data32 xchg %ax,%ax ASM_CLAC ret retq Signed-off-by: Adrian Hunter <adrian.hunter@intel.com> Cc: David Ahern <dsahern@gmail.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Ingo Molnar <mingo@kernel.org> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Mike Galbraith <efault@gmx.de> Cc: Namhyung Kim <namhyung@gmail.com> Cc: Paul Mackerras <paulus@samba.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Stephane Eranian <eranian@google.com> Link: http://lkml.kernel.org/r/1379009721-27667-1-git-send-email-adrian.hunter@intel.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

The crash[1] is found by xfstests/generic/208 with "-o compress", it's not reproduced everytime, but it does panic. The bug is quite interesting, it's actually introduced by a recent commit (573aeca, Btrfs: actually limit the size of delalloc range). Btrfs implements delay allocation, so during writeback, we (1) get a page A and lock it (2) search the state tree for delalloc bytes and lock all pages within the range (3) process the delalloc range, including find disk space and create ordered extent and so on. (4) submit the page A. It runs well in normal cases, but if we're in a racy case, eg. buffered compressed writes and aio-dio writes, sometimes we may fail to lock all pages in the 'delalloc' range, in which case, we need to fall back to search the state tree again with a smaller range limit(max_bytes = PAGE_CACHE_SIZE - offset). The mentioned commit has a side effect, that is, in the fallback case, we can find delalloc bytes before the index of the page we already have locked, so we're in the case of (delalloc_end <= *start) and return with (found > 0). This ends with not locking delalloc pages but making ->writepage still process them, and the crash happens. This fixes it by just thinking that we find nothing and returning to caller as the caller knows how to deal with it properly. [1]: ------------[ cut here ]------------ kernel BUG at mm/page-writeback.c:2170! [...] CPU: 2 PID: 11755 Comm: btrfs-delalloc- Tainted: G O 3.11.0+ #8 [...] RIP: 0010:[<ffffffff810f5093>] [<ffffffff810f5093>] clear_page_dirty_for_io+0x1e/0x83 [...] [ 4934.248731] Stack: [ 4934.248731] ffff8801477e5dc8 ffffea00049b9f00 ffff8801869f9ce8 ffffffffa02b841a [ 4934.248731] 0000000000000000 0000000000000000 0000000000000fff 0000000000000620 [ 4934.248731] ffff88018db59c78 ffffea0005da8d40 ffffffffa02ff860 00000001810016c0 [ 4934.248731] Call Trace: [ 4934.248731] [<ffffffffa02b841a>] extent_range_clear_dirty_for_io+0xcf/0xf5 [btrfs] [ 4934.248731] [<ffffffffa02a8889>] compress_file_range+0x1dc/0x4cb [btrfs] [ 4934.248731] [<ffffffff8104f7af>] ? detach_if_pending+0x22/0x4b [ 4934.248731] [<ffffffffa02a8bad>] async_cow_start+0x35/0x53 [btrfs] [ 4934.248731] [<ffffffffa02c694b>] worker_loop+0x14b/0x48c [btrfs] [ 4934.248731] [<ffffffffa02c6800>] ? btrfs_queue_worker+0x25c/0x25c [btrfs] [ 4934.248731] [<ffffffff810608f5>] kthread+0x8d/0x95 [ 4934.248731] [<ffffffff81060868>] ? kthread_freezable_should_stop+0x43/0x43 [ 4934.248731] [<ffffffff814fe09c>] ret_from_fork+0x7c/0xb0 [ 4934.248731] [<ffffffff81060868>] ? kthread_freezable_should_stop+0x43/0x43 [ 4934.248731] Code: ff 85 c0 0f 94 c0 0f b6 c0 59 5b 5d c3 0f 1f 44 00 00 55 48 89 e5 41 54 53 48 89 fb e8 2c de 00 00 49 89 c4 48 8b 03 a8 01 75 02 <0f> 0b 4d 85 e4 74 52 49 8b 84 24 80 00 00 00 f6 40 20 01 75 44 [ 4934.248731] RIP [<ffffffff810f5093>] clear_page_dirty_for_io+0x1e/0x83 [ 4934.248731] RSP <ffff8801869f9c48> [ 4934.280307] ---[ end trace 36f06d3f8750236a ]--- Signed-off-by: Liu Bo <bo.li.liu@oracle.com> Signed-off-by: Josef Bacik <jbacik@fusionio.com>

…ux/kernel/git/tip/tip Pull x86 boot changes from Ingo Molnar: "Two changes that prettify and compactify the SMP bootup output from: smpboot: Booting Node 0, Processors #1 #2 #3 OK smpboot: Booting Node 1, Processors #4 #5 #6 #7 OK smpboot: Booting Node 2, Processors #8 #9 #10 #11 OK smpboot: Booting Node 3, Processors #12 #13 #14 #15 OK Brought up 16 CPUs to something like: x86: Booting SMP configuration: .... node #0, CPUs: #1 #2 #3 .... node #1, CPUs: #4 #5 #6 #7 .... node #2, CPUs: #8 #9 #10 #11 .... node #3, CPUs: #12 #13 #14 #15 x86: Booted up 4 nodes, 16 CPUs" * 'x86-boot-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/boot: Further compress CPUs bootup message x86: Improve the printout of the SMP bootup CPU table

Lockdep reported that there is a potential for deadlock because vcpu->arch.tbacct_lock is not irq-safe, and is sometimes taken inside the rq_lock (run-queue lock) in the scheduler, which is taken within interrupts. The lockdep splat looks like: ====================================================== [ INFO: HARDIRQ-safe -> HARDIRQ-unsafe lock order detected ] 3.12.0-rc5-kvm+ #8 Not tainted ------------------------------------------------------ qemu-system-ppc/4803 [HC0[0]:SC0[0]:HE0:SE1] is trying to acquire: (&(&vcpu->arch.tbacct_lock)->rlock){+.+...}, at: [<c0000000000947ac>] .kvmppc_core_vcpu_put_hv+0x2c/0xa0 and this task is already holding: (&rq->lock){-.-.-.}, at: [<c000000000ac16c0>] .__schedule+0x180/0xaa0 which would create a new lock dependency: (&rq->lock){-.-.-.} -> (&(&vcpu->arch.tbacct_lock)->rlock){+.+...} but this new dependency connects a HARDIRQ-irq-safe lock: (&rq->lock){-.-.-.} ... which became HARDIRQ-irq-safe at: [<c00000000013797c>] .lock_acquire+0xbc/0x190 [<c000000000ac3c74>] ._raw_spin_lock+0x34/0x60 [<c0000000000f8564>] .scheduler_tick+0x54/0x180 [<c0000000000c2610>] .update_process_times+0x70/0xa0 [<c00000000012cdfc>] .tick_periodic+0x3c/0xe0 [<c00000000012cec8>] .tick_handle_periodic+0x28/0xb0 [<c00000000001ef40>] .timer_interrupt+0x120/0x2e0 [<c000000000002868>] decrementer_common+0x168/0x180 [<c0000000001c7ca4>] .get_page_from_freelist+0x924/0xc10 [<c0000000001c8e00>] .__alloc_pages_nodemask+0x200/0xba0 [<c0000000001c9eb8>] .alloc_pages_exact_nid+0x68/0x110 [<c000000000f4c3ec>] .page_cgroup_init+0x1e0/0x270 [<c000000000f24480>] .start_kernel+0x3e0/0x4e4 [<c000000000009d30>] .start_here_common+0x20/0x70 to a HARDIRQ-irq-unsafe lock: (&(&vcpu->arch.tbacct_lock)->rlock){+.+...} ... which became HARDIRQ-irq-unsafe at: ... [<c00000000013797c>] .lock_acquire+0xbc/0x190 [<c000000000ac3c74>] ._raw_spin_lock+0x34/0x60 [<c0000000000946ac>] .kvmppc_core_vcpu_load_hv+0x2c/0x100 [<c00000000008394c>] .kvmppc_core_vcpu_load+0x2c/0x40 [<c000000000081000>] .kvm_arch_vcpu_load+0x10/0x30 [<c00000000007afd4>] .vcpu_load+0x64/0xd0 [<c00000000007b0f8>] .kvm_vcpu_ioctl+0x68/0x730 [<c00000000025530c>] .do_vfs_ioctl+0x4dc/0x7a0 [<c000000000255694>] .SyS_ioctl+0xc4/0xe0 [<c000000000009ee4>] syscall_exit+0x0/0x98 Some users have reported this deadlock occurring in practice, though the reports have been primarily on 3.10.x-based kernels. This fixes the problem by making tbacct_lock be irq-safe. Signed-off-by: Paul Mackerras <paulus@samba.org> Signed-off-by: Alexander Graf <agraf@suse.de>

the 'soc' node in the common .dtsi for MPC5121 has an '#interrupt-cells' property although this node is not an interrupt controller remove this erroneously placed property because starting with v3.13-rc1 lookup and resolution of 'interrupts' specs for peripherals gets misled, emits 'no irq domain found' WARN() messages and breaks the boot process irq: no irq domain found for /soc@80000000 ! ------------[ cut here ]------------ WARNING: at drivers/of/platform.c:171 Modules linked in: CPU: 0 PID: 1 Comm: swapper Tainted: G W 3.13.0-rc1-00001-g8a66234 #8 task: df823bb0 ti: df834000 task.ti: df834000 NIP: c02b5190 LR: c02b5180 CTR: c01cf4e0 REGS: df835c50 TRAP: 0700 Tainted: G W (3.13.0-rc1-00001-g8a66234) MSR: 00029032 <EE,ME,IR,DR,RI> CR: 229a9d42 XER: 20000000 GPR00: c02b5180 df835d00 df823bb0 00000000 00000000 df835b18 ffffffff 00000308 GPR08: c0479cc0 c0480000 c0479cc0 00000308 00000308 00000000 c00040fc 00000000 GPR16: 00000000 00000000 00000000 00000000 00000000 00000000 00000000 df850880 GPR24: df84d670 00000000 00000001 df8561a dffffccc df85089c 00000020 00000001 NIP [c02b5190] of_device_alloc+0xf4/0x1a0 LR [c02b5180] of_device_alloc+0xe4/0x1a0 Call Trace: [df835d00] [c02b5180] of_device_alloc+0xe4/0x1a0 (unreliable) [df835d50] [c02b5278] of_platform_device_create_pdata+0x3c/0xc8 [df835d70] [c02b53fc] of_platform_bus_create+0xf8/0x170 [df835dc0] [c02b5448] of_platform_bus_create+0x144/0x170 [df835e10] [c02b55a8] of_platform_bus_probe+0x98/0xe8 [df835e30] [c0437508] mpc512x_init+0x28/0x1c4 [df835e7] [c0435de8] ppc_init+0x4c/0x60 [df835e80] [c0003b28] do_one_initcall+0x150/0x1a4 [df835ef0] [c0432048] kernel_init_freeable+0x114/0x1c0 [df835f30] [c0004114] kernel_init+0x18/0x124 [df835f40] [c000e910] ret_from_kernel_thread+0x5c/0x64 Instruction dump: 409effd4 57c9103a 57de2834 7c89f050 7f83e378 7c972214 7f45d37 48001f55 7c63d278 7c630034 5463d97e 687a0001 <0f1a0000> 2f990000 387b0010 939b0098 ---[ end trace 2257f10e5a20cbdd ]--- ... irq: no irq domain found for /soc@80000000 ! fsl-diu-fb 80002100.display: could not get DIU IRQ fsl-diu-fb: probe of 80002100.display failed with error -22 irq: no irq domain found for /soc@80000000 ! mpc512x_dma 80014000.dma: Error mapping IRQ! mpc512x_dma: probe of 80014000.dma failed with error -22 ... irq: no irq domain found for /soc@80000000 ! fs_enet: probe of 80002800.ethernet failed with error -22 ... irq: no irq domain found for /soc@80000000 ! mpc5121-rtc 80000a00.rtc: mpc5121_rtc_probe: could not request irq: 0 mpc5121-rtc: probe of 80000a00.rtc failed with error -22 ... Cc: Anatolij Gustschin <agust@denx.de> Cc: linuxppc-dev@lists.ozlabs.org Cc: devicetree@vger.kernel.org Signed-off-by: Gerhard Sittig <gsi@denx.de> Signed-off-by: Anatolij Gustschin <agust@denx.de>

…king Daniel Borkmann reported a VM_BUG_ON assertion failing: ------------[ cut here ]------------ kernel BUG at mm/mlock.c:528! invalid opcode: 0000 [#1] SMP Modules linked in: ccm arc4 iwldvm [...] video CPU: 3 PID: 2266 Comm: netsniff-ng Not tainted 3.14.0-rc2+ #8 Hardware name: LENOVO 2429BP3/2429BP3, BIOS G4ET37WW (1.12 ) 05/29/2012 task: ffff8801f87f9820 ti: ffff88002cb44000 task.ti: ffff88002cb44000 RIP: 0010:[<ffffffff81171ad0>] [<ffffffff81171ad0>] munlock_vma_pages_range+0x2e0/0x2f0 Call Trace: do_munmap+0x18f/0x3b0 vm_munmap+0x41/0x60 SyS_munmap+0x22/0x30 system_call_fastpath+0x1a/0x1f RIP munlock_vma_pages_range+0x2e0/0x2f0 ---[ end trace a0088dcf07ae10f2 ]--- because munlock_vma_pages_range() thinks it's unexpectedly in the middle of a THP page. This can be reproduced with default config since 3.11 kernels. A reproducer can be found in the kernel's selftest directory for networking by running ./psock_tpacket. The problem is that an order=2 compound page (allocated by alloc_one_pg_vec_page() is part of the munlocked VM_MIXEDMAP vma (mapped by packet_mmap()) and mistaken for a THP page and assumed to be order=9. The checks for THP in munlock came with commit ff6a6da ("mm: accelerate munlock() treatment of THP pages"), i.e. since 3.9, but did not trigger a bug. It just makes munlock_vma_pages_range() skip such compound pages until the next 512-pages-aligned page, when it encounters a head page. This is however not a problem for vma's where mlocking has no effect anyway, but it can distort the accounting. Since commit 7225522 ("mm: munlock: batch non-THP page isolation and munlock+putback using pagevec") this can trigger a VM_BUG_ON in PageTransHuge() check. This patch fixes the issue by adding VM_MIXEDMAP flag to VM_SPECIAL, a list of flags that make vma's non-mlockable and non-mergeable. The reasoning is that VM_MIXEDMAP vma's are similar to VM_PFNMAP, which is already on the VM_SPECIAL list, and both are intended for non-LRU pages where mlocking makes no sense anyway. Related Lkml discussion can be found in [2]. [1] tools/testing/selftests/net/psock_tpacket [2] https://lkml.org/lkml/2014/1/10/427 Signed-off-by: Vlastimil Babka <vbabka@suse.cz> Signed-off-by: Daniel Borkmann <dborkman@redhat.com> Reported-by: Daniel Borkmann <dborkman@redhat.com> Tested-by: Daniel Borkmann <dborkman@redhat.com> Cc: Thomas Hellstrom <thellstrom@vmware.com> Cc: John David Anglin <dave.anglin@bell.net> Cc: HATAYAMA Daisuke <d.hatayama@jp.fujitsu.com> Cc: Konstantin Khlebnikov <khlebnikov@openvz.org> Cc: Carsten Otte <cotte@de.ibm.com> Cc: Jared Hulbert <jaredeh@gmail.com> Tested-by: Hannes Frederic Sowa <hannes@stressinduktion.org> Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Acked-by: Rik van Riel <riel@redhat.com> Cc: Andrea Arcangeli <aarcange@redhat.com> Cc: <stable@vger.kernel.org> [3.11.x+] Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

vmxnet3's netpoll driver is incorrectly coded. It directly calls vmxnet3_do_poll, which is the driver internal napi poll routine. As the netpoll controller method doesn't block real napi polls in any way, there is a potential for race conditions in which the netpoll controller method and the napi poll method run concurrently. The result is data corruption causing panics such as this one recently observed: PID: 1371 TASK: ffff88023762caa0 CPU: 1 COMMAND: "rs:main Q:Reg" #0 [ffff88023abd5780] machine_kexec at ffffffff81038f3b #1 [ffff88023abd57e0] crash_kexec at ffffffff810c5d92 #2 [ffff88023abd58b0] oops_end at ffffffff8152b570 #3 [ffff88023abd58e0] die at ffffffff81010e0b #4 [ffff88023abd5910] do_trap at ffffffff8152add4 #5 [ffff88023abd5970] do_invalid_op at ffffffff8100cf95 #6 [ffff88023abd5a10] invalid_op at ffffffff8100bf9b [exception RIP: vmxnet3_rq_rx_complete+1968] RIP: ffffffffa00f1e80 RSP: ffff88023abd5ac8 RFLAGS: 00010086 RAX: 0000000000000000 RBX: ffff88023b5dcee0 RCX: 00000000000000c0 RDX: 0000000000000000 RSI: 00000000000005f2 RDI: ffff88023b5dcee0 RBP: ffff88023abd5b48 R8: 0000000000000000 R9: ffff88023a3b6048 R10: 0000000000000000 R11: 0000000000000002 R12: ffff8802398d4cd8 R13: ffff88023af35140 R14: ffff88023b60c890 R15: 0000000000000000 ORIG_RAX: ffffffffffffffff CS: 0010 SS: 0018 #7 [ffff88023abd5b50] vmxnet3_do_poll at ffffffffa00f204a [vmxnet3] #8 [ffff88023abd5b80] vmxnet3_netpoll at ffffffffa00f209c [vmxnet3] #9 [ffff88023abd5ba0] netpoll_poll_dev at ffffffff81472bb7 The fix is to do as other drivers do, and have the poll controller call the top half interrupt handler, which schedules a napi poll properly to recieve frames Tested by myself, successfully. Signed-off-by: Neil Horman <nhorman@tuxdriver.com> CC: Shreyas Bhatewara <sbhatewara@vmware.com> CC: "VMware, Inc." <pv-drivers@vmware.com> CC: "David S. Miller" <davem@davemloft.net> CC: stable@vger.kernel.org Reviewed-by: Shreyas N Bhatewara <sbhatewara@vmware.com> Signed-off-by: David S. Miller <davem@davemloft.net>

commit ec183d2 upstream. Fixes segmentation fault using, for instance: (gdb) run record -I -e intel_pt/tsc=1,noretcomp=1/u /bin/ls Starting program: /home/acme/bin/perf record -I -e intel_pt/tsc=1,noretcomp=1/u /bin/ls Missing separate debuginfos, use: dnf debuginfo-install glibc-2.22-7.fc23.x86_64 [Thread debugging using libthread_db enabled] Using host libthread_db library "/lib64/libthread_db.so.1". Program received signal SIGSEGV, Segmentation fault. 0 x00000000004b9ea5 in tracepoint_error (e=0x0, err=13, sys=0x19b1370 "sched", name=0x19a5d00 "sched_switch") at util/parse-events.c:410 (gdb) bt #0 0x00000000004b9ea5 in tracepoint_error (e=0x0, err=13, sys=0x19b1370 "sched", name=0x19a5d00 "sched_switch") at util/parse-events.c:410 #1 0x00000000004b9fc5 in add_tracepoint (list=0x19a5d20, idx=0x7fffffffb8c0, sys_name=0x19b1370 "sched", evt_name=0x19a5d00 "sched_switch", err=0x0, head_config=0x0) at util/parse-events.c:433 #2 0x00000000004ba334 in add_tracepoint_event (list=0x19a5d20, idx=0x7fffffffb8c0, sys_name=0x19b1370 "sched", evt_name=0x19a5d00 "sched_switch", err=0x0, head_config=0x0) at util/parse-events.c:498 #3 0x00000000004bb699 in parse_events_add_tracepoint (list=0x19a5d20, idx=0x7fffffffb8c0, sys=0x19b1370 "sched", event=0x19a5d00 "sched_switch", err=0x0, head_config=0x0) at util/parse-events.c:936 #4 0x00000000004f6eda in parse_events_parse (_data=0x7fffffffb8b0, scanner=0x19a49d0) at util/parse-events.y:391 #5 0x00000000004bc8e5 in parse_events__scanner (str=0x663ff2 "sched:sched_switch", data=0x7fffffffb8b0, start_token=258) at util/parse-events.c:1361 #6 0x00000000004bca57 in parse_events (evlist=0x19a5220, str=0x663ff2 "sched:sched_switch", err=0x0) at util/parse-events.c:1401 #7 0x0000000000518d5f in perf_evlist__can_select_event (evlist=0x19a3b90, str=0x663ff2 "sched:sched_switch") at util/record.c:253 #8 0x0000000000553c42 in intel_pt_track_switches (evlist=0x19a3b90) at arch/x86/util/intel-pt.c:364 #9 0x00000000005549d1 in intel_pt_recording_options (itr=0x19a2c40, evlist=0x19a3b90, opts=0x8edf68 <record+232>) at arch/x86/util/intel-pt.c:664 #10 0x000000000051e076 in auxtrace_record__options (itr=0x19a2c40, evlist=0x19a3b90, opts=0x8edf68 <record+232>) at util/auxtrace.c:539 #11 0x0000000000433368 in cmd_record (argc=1, argv=0x7fffffffde60, prefix=0x0) at builtin-record.c:1264 #12 0x000000000049bec2 in run_builtin (p=0x8fa2a8 <commands+168>, argc=5, argv=0x7fffffffde60) at perf.c:390 #13 0x000000000049c12a in handle_internal_command (argc=5, argv=0x7fffffffde60) at perf.c:451 #14 0x000000000049c278 in run_argv (argcp=0x7fffffffdcbc, argv=0x7fffffffdcb0) at perf.c:495 #15 0x000000000049c60a in main (argc=5, argv=0x7fffffffde60) at perf.c:618 (gdb) Intel PT attempts to find the sched:sched_switch tracepoint but that seg faults if tracefs is not readable, because the error reporting structure is null, as errors are not reported when automatically adding tracepoints. Fix by checking before using. Committer note: This doesn't take place in a kernel that supports perf_event_attr.context_switch, that is the default way that will be used for tracking context switches, only in older kernels, like 4.2, in a machine with Intel PT (e.g. Broadwell) for non-priviledged users. Further info from a similar patch by Wang: The error is in tracepoint_error: it assumes the 'e' parameter is valid. However, there are many situation a parse_event() can be called without parse_events_error. See result of $ grep 'parse_events(.*NULL)' ./tools/perf/ -r' Signed-off-by: Adrian Hunter <adrian.hunter@intel.com> Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Josh Poimboeuf <jpoimboe@redhat.com> Cc: Tong Zhang <ztong@vt.edu> Cc: Wang Nan <wangnan0@huawei.com> Fixes: 1965817 ("perf tools: Enhance parsing events tracepoint error output") Link: http://lkml.kernel.org/r/1453809921-24596-2-git-send-email-adrian.hunter@intel.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

commit 420902c upstream. If we hold the superblock lock while calling reiserfs_quota_on_mount(), we can deadlock our own worker - mount blocks kworker/3:2, sleeps forever more. crash> ps|grep UN 715 2 3 ffff880220734d30 UN 0.0 0 0 [kworker/3:2] 9369 9341 2 ffff88021ffb7560 UN 1.3 493404 123184 Xorg 9665 9664 3 ffff880225b92ab0 UN 0.0 47368 812 udisks-daemon 10635 10403 3 ffff880222f22c70 UN 0.0 14904 936 mount crash> bt ffff880220734d30 PID: 715 TASK: ffff880220734d30 CPU: 3 COMMAND: "kworker/3:2" #0 [ffff8802244c3c20] schedule at ffffffff8144584b #1 [ffff8802244c3cc8] __rt_mutex_slowlock at ffffffff814472b3 #2 [ffff8802244c3d28] rt_mutex_slowlock at ffffffff814473f5 #3 [ffff8802244c3dc8] reiserfs_write_lock at ffffffffa05f28fd [reiserfs] #4 [ffff8802244c3de8] flush_async_commits at ffffffffa05ec91d [reiserfs] #5 [ffff8802244c3e08] process_one_work at ffffffff81073726 #6 [ffff8802244c3e68] worker_thread at ffffffff81073eba #7 [ffff8802244c3ec8] kthread at ffffffff810782e0 #8 [ffff8802244c3f48] kernel_thread_helper at ffffffff81450064 crash> rd ffff8802244c3cc8 10 ffff8802244c3cc8: ffffffff814472b3 ffff880222f23250 .rD.....P2.".... ffff8802244c3cd8: 0000000000000000 0000000000000286 ................ ffff8802244c3ce8: ffff8802244c3d30 ffff880220734d80 0=L$.....Ms .... ffff8802244c3cf8: ffff880222e8f628 0000000000000000 (.."............ ffff8802244c3d08: 0000000000000000 0000000000000002 ................ crash> struct rt_mutex ffff880222e8f628 struct rt_mutex { wait_lock = { raw_lock = { slock = 65537 } }, wait_list = { node_list = { next = 0xffff8802244c3d48, prev = 0xffff8802244c3d48 } }, owner = 0xffff880222f22c71, save_state = 0 } crash> bt 0xffff880222f22c70 PID: 10635 TASK: ffff880222f22c70 CPU: 3 COMMAND: "mount" #0 [ffff8802216a9868] schedule at ffffffff8144584b #1 [ffff8802216a9910] schedule_timeout at ffffffff81446865 #2 [ffff8802216a99a0] wait_for_common at ffffffff81445f74 #3 [ffff8802216a9a30] flush_work at ffffffff810712d3 #4 [ffff8802216a9ab0] schedule_on_each_cpu at ffffffff81074463 #5 [ffff8802216a9ae0] invalidate_bdev at ffffffff81178aba #6 [ffff8802216a9af0] vfs_load_quota_inode at ffffffff811a3632 #7 [ffff8802216a9b50] dquot_quota_on_mount at ffffffff811a375c #8 [ffff8802216a9b80] finish_unfinished at ffffffffa05dd8b0 [reiserfs] #9 [ffff8802216a9cc0] reiserfs_fill_super at ffffffffa05de825 [reiserfs] RIP: 00007f7b9303997a RSP: 00007ffff443c7a8 RFLAGS: 00010202 RAX: 00000000000000a5 RBX: ffffffff8144ef12 RCX: 00007f7b932e9ee0 RDX: 00007f7b93d9a400 RSI: 00007f7b93d9a3e0 RDI: 00007f7b93d9a3c0 RBP: 00007f7b93d9a2c0 R8: 00007f7b93d9a550 R9: 0000000000000001 R10: ffffffffc0ed040e R11: 0000000000000202 R12: 000000000000040e R13: 0000000000000000 R14: 00000000c0ed040e R15: 00007ffff443ca20 ORIG_RAX: 00000000000000a5 CS: 0033 SS: 002b Signed-off-by: Mike Galbraith <efault@gmx.de> Acked-by: Frederic Weisbecker <fweisbec@gmail.com> Acked-by: Mike Galbraith <mgalbraith@suse.de> Signed-off-by: Jan Kara <jack@suse.cz> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

commit b6bc1c7 upstream. Function ib_create_qp() was failing to return an error when rdma_rw_init_mrs() fails, causing a crash further down in ib_create_qp() when trying to dereferece the qp pointer which was actually a negative errno. The crash: crash> log|grep BUG [ 136.458121] BUG: unable to handle kernel NULL pointer dereference at 0000000000000098 crash> bt PID: 3736 TASK: ffff8808543215c0 CPU: 2 COMMAND: "kworker/u64:2" #0 [ffff88084d323340] machine_kexec at ffffffff8105fbb0 #1 [ffff88084d3233b0] __crash_kexec at ffffffff81116758 #2 [ffff88084d323480] crash_kexec at ffffffff8111682d #3 [ffff88084d3234b0] oops_end at ffffffff81032bd6 #4 [ffff88084d3234e0] no_context at ffffffff8106e431 #5 [ffff88084d323530] __bad_area_nosemaphore at ffffffff8106e610 #6 [ffff88084d323590] bad_area_nosemaphore at ffffffff8106e6f4 #7 [ffff88084d3235a0] __do_page_fault at ffffffff8106ebdc #8 [ffff88084d323620] do_page_fault at ffffffff8106f057 #9 [ffff88084d323660] page_fault at ffffffff816e3148 [exception RIP: ib_create_qp+427] RIP: ffffffffa02554fb RSP: ffff88084d323718 RFLAGS: 00010246 RAX: 0000000000000004 RBX: fffffffffffffff4 RCX: 000000018020001f RDX: ffff880830997fc0 RSI: 0000000000000001 RDI: ffff88085f407200 RBP: ffff88084d323778 R8: 0000000000000001 R9: ffffea0020bae210 R10: ffffea0020bae218 R11: 0000000000000001 R12: ffff88084d3237c8 R13: 00000000fffffff4 R14: ffff880859fa5000 R15: ffff88082eb89800 ORIG_RAX: ffffffffffffffff CS: 0010 SS: 0018 #10 [ffff88084d323780] rdma_create_qp at ffffffffa0782681 [rdma_cm] #11 [ffff88084d3237b0] nvmet_rdma_create_queue_ib at ffffffffa07c43f3 [nvmet_rdma] #12 [ffff88084d323860] nvmet_rdma_alloc_queue at ffffffffa07c5ba9 [nvmet_rdma] #13 [ffff88084d323900] nvmet_rdma_queue_connect at ffffffffa07c5c96 [nvmet_rdma] #14 [ffff88084d323980] nvmet_rdma_cm_handler at ffffffffa07c6450 [nvmet_rdma] #15 [ffff88084d3239b0] iw_conn_req_handler at ffffffffa0787480 [rdma_cm] #16 [ffff88084d323a60] cm_conn_req_handler at ffffffffa0775f06 [iw_cm] #17 [ffff88084d323ab0] process_event at ffffffffa0776019 [iw_cm] #18 [ffff88084d323af0] cm_work_handler at ffffffffa0776170 [iw_cm] #19 [ffff88084d323cb0] process_one_work at ffffffff810a1483 #20 [ffff88084d323d90] worker_thread at ffffffff810a211d #21 [ffff88084d323ec0] kthread at ffffffff810a6c5c #22 [ffff88084d323f50] ret_from_fork at ffffffff816e1ebf Fixes: 632bc3f ("IB/core, RDMA RW API: Do not exceed QP SGE send limit") Signed-off-by: Steve Wise <swise@opengridcomputing.com> Reviewed-by: Bart Van Assche <bart.vanassche@sandisk.com> Signed-off-by: Doug Ledford <dledford@redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

commit 346e997 upstream. If a device is unplugged and replugged during Sx system suspend some Intel xHC hosts will overwrite the CAS (Cold attach status) flag and no device connection is noticed in resume. A device in this state can be identified in resume if its link state is in polling or compliance mode, and the current connect status is 0. A device in this state needs to be warm reset. Intel 100/c230 series PCH specification update Doc #332692-006 Errata #8 Observed on Cherryview and Apollolake as they go into compliance mode if LFPS times out during polling, and re-plugged devices are not discovered at resume. Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

commit f46c445 upstream. When I push NFSv4.1 / RDMA hard, (xfstests generic/089, for example), I get this crash on the server: Oct 28 22:04:30 klimt kernel: general protection fault: 0000 [#1] SMP DEBUG_PAGEALLOC Oct 28 22:04:30 klimt kernel: Modules linked in: cts rpcsec_gss_krb5 iTCO_wdt iTCO_vendor_support sb_edac edac_core x86_pkg_temp_thermal intel_powerclamp coretemp kvm_intel kvm btrfs irqbypass crct10dif_pclmul crc32_pclmul ghash_clmulni_intel aesni_intel lrw gf128mul glue_helper ablk_helper cryptd xor pcspkr raid6_pq i2c_i801 i2c_smbus lpc_ich mfd_core sg mei_me mei ioatdma shpchp wmi ipmi_si ipmi_msghandler rpcrdma ib_ipoib rdma_ucm acpi_power_meter acpi_pad ib_ucm ib_uverbs ib_umad rdma_cm ib_cm iw_cm nfsd auth_rpcgss nfs_acl lockd grace sunrpc ip_tables xfs libcrc32c mlx4_ib mlx4_en ib_core sr_mod cdrom sd_mod ast drm_kms_helper syscopyarea sysfillrect sysimgblt fb_sys_fops ttm drm crc32c_intel igb ahci libahci ptp mlx4_core pps_core dca libata i2c_algo_bit i2c_core dm_mirror dm_region_hash dm_log dm_mod Oct 28 22:04:30 klimt kernel: CPU: 7 PID: 1558 Comm: nfsd Not tainted 4.9.0-rc2-00005-g82cd754 #8 Oct 28 22:04:30 klimt kernel: Hardware name: Supermicro Super Server/X10SRL-F, BIOS 1.0c 09/09/2015 Oct 28 22:04:30 klimt kernel: task: ffff880835c3a100 task.stack: ffff8808420d8000 Oct 28 22:04:30 klimt kernel: RIP: 0010:[<ffffffffa05a759f>] [<ffffffffa05a759f>] release_lock_stateid+0x1f/0x60 [nfsd] Oct 28 22:04:30 klimt kernel: RSP: 0018:ffff8808420dbce0 EFLAGS: 00010246 Oct 28 22:04:30 klimt kernel: RAX: ffff88084e6660f0 RBX: ffff88084e667020 RCX: 0000000000000000 Oct 28 22:04:30 klimt kernel: RDX: 0000000000000007 RSI: 0000000000000000 RDI: ffff88084e667020 Oct 28 22:04:30 klimt kernel: RBP: ffff8808420dbcf8 R08: 0000000000000001 R09: 0000000000000000 Oct 28 22:04:30 klimt kernel: R10: ffff880835c3a100 R11: ffff880835c3aca8 R12: 6b6b6b6b6b6b6b6b Oct 28 22:04:30 klimt kernel: R13: ffff88084e6670d8 R14: ffff880835f546f0 R15: ffff880835f1c548 Oct 28 22:04:30 klimt kernel: FS: 0000000000000000(0000) GS:ffff88087bdc0000(0000) knlGS:0000000000000000 Oct 28 22:04:30 klimt kernel: CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 Oct 28 22:04:30 klimt kernel: CR2: 00007ff020389000 CR3: 0000000001c06000 CR4: 00000000001406e0 Oct 28 22:04:30 klimt kernel: Stack: Oct 28 22:04:30 klimt kernel: ffff88084e667020 0000000000000000 ffff88084e6670d8 ffff8808420dbd20 Oct 28 22:04:30 klimt kernel: ffffffffa05ac80d ffff880835f54548 ffff88084e640008 ffff880835f545b0 Oct 28 22:04:30 klimt kernel: ffff8808420dbd70 ffffffffa059803d ffff880835f1c768 0000000000000870 Oct 28 22:04:30 klimt kernel: Call Trace: Oct 28 22:04:30 klimt kernel: [<ffffffffa05ac80d>] nfsd4_free_stateid+0xfd/0x1b0 [nfsd] Oct 28 22:04:30 klimt kernel: [<ffffffffa059803d>] nfsd4_proc_compound+0x40d/0x690 [nfsd] Oct 28 22:04:30 klimt kernel: [<ffffffffa0583114>] nfsd_dispatch+0xd4/0x1d0 [nfsd] Oct 28 22:04:30 klimt kernel: [<ffffffffa047bbf9>] svc_process_common+0x3d9/0x700 [sunrpc] Oct 28 22:04:30 klimt kernel: [<ffffffffa047ca64>] svc_process+0xf4/0x330 [sunrpc] Oct 28 22:04:30 klimt kernel: [<ffffffffa05827ca>] nfsd+0xfa/0x160 [nfsd] Oct 28 22:04:30 klimt kernel: [<ffffffffa05826d0>] ? nfsd_destroy+0x170/0x170 [nfsd] Oct 28 22:04:30 klimt kernel: [<ffffffff810b367b>] kthread+0x10b/0x120 Oct 28 22:04:30 klimt kernel: [<ffffffff810b3570>] ? kthread_stop+0x280/0x280 Oct 28 22:04:30 klimt kernel: [<ffffffff8174e8ba>] ret_from_fork+0x2a/0x40 Oct 28 22:04:30 klimt kernel: Code: c3 66 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 55 48 89 e5 41 55 41 54 53 48 8b 87 b0 00 00 00 48 89 fb 4c 8b a0 98 00 00 00 <49> 8b 44 24 20 48 8d b8 80 03 00 00 e8 10 66 1a e1 48 89 df e8 Oct 28 22:04:30 klimt kernel: RIP [<ffffffffa05a759f>] release_lock_stateid+0x1f/0x60 [nfsd] Oct 28 22:04:30 klimt kernel: RSP <ffff8808420dbce0> Oct 28 22:04:30 klimt kernel: ---[ end trace cf5d0b371973e167 ]--- Jeff Layton says: > Hm...now that I look though, this is a little suspicious: > > struct nfs4_openowner *oo = openowner(stp->st_openstp->st_stateowner); > > I wonder if it's possible for the openstateid to have already been > destroyed at this point. > > We might be better off doing something like this to get the client pointer: > > stp->st_stid.sc_client; > > ...which should be more direct and less dependent on other stateids > staying valid. With the suggested change, I am no longer able to reproduce the above oops. v2: Fix unhash_lock_stateid() as well Fix-suggested-by: Jeff Layton <jlayton@redhat.com> Fixes: 4269139 ('nfsd: Fix race between FREE_STATEID and LOCK') Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Reviewed-by: Jeff Layton <jlayton@redhat.com> Signed-off-by: J. Bruce Fields <bfields@redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

[ Upstream commit 45caeaa ] As Eric Dumazet pointed out this also needs to be fixed in IPv6. v2: Contains the IPv6 tcp/Ipv6 dccp patches as well. We have seen a few incidents lately where a dst_enty has been freed with a dangling TCP socket reference (sk->sk_dst_cache) pointing to that dst_entry. If the conditions/timings are right a crash then ensues when the freed dst_entry is referenced later on. A Common crashing back trace is: #8 [] page_fault at ffffffff8163e648 [exception RIP: __tcp_ack_snd_check+74] . . #9 [] tcp_rcv_established at ffffffff81580b64 #10 [] tcp_v4_do_rcv at ffffffff8158b54a #11 [] tcp_v4_rcv at ffffffff8158cd02 #12 [] ip_local_deliver_finish at ffffffff815668f4 #13 [] ip_local_deliver at ffffffff81566bd9 #14 [] ip_rcv_finish at ffffffff8156656d #15 [] ip_rcv at ffffffff81566f06 #16 [] __netif_receive_skb_core at ffffffff8152b3a2 #17 [] __netif_receive_skb at ffffffff8152b608 #18 [] netif_receive_skb at ffffffff8152b690 #19 [] vmxnet3_rq_rx_complete at ffffffffa015eeaf [vmxnet3] #20 [] vmxnet3_poll_rx_only at ffffffffa015f32a [vmxnet3] #21 [] net_rx_action at ffffffff8152bac2 #22 [] __do_softirq at ffffffff81084b4f #23 [] call_softirq at ffffffff8164845c #24 [] do_softirq at ffffffff81016fc5 #25 [] irq_exit at ffffffff81084ee5 #26 [] do_IRQ at ffffffff81648ff8 Of course it may happen with other NIC drivers as well. It's found the freed dst_entry here: 224 static bool tcp_in_quickack_mode(struct sock *sk)↩ 225 {↩ 226 ▹ const struct inet_connection_sock *icsk = inet_csk(sk);↩ 227 ▹ const struct dst_entry *dst = __sk_dst_get(sk);↩ 228 ↩ 229 ▹ return (dst && dst_metric(dst, RTAX_QUICKACK)) ||↩ 230 ▹ ▹ (icsk->icsk_ack.quick && !icsk->icsk_ack.pingpong);↩ 231 }↩ But there are other backtraces attributed to the same freed dst_entry in netfilter code as well. All the vmcores showed 2 significant clues: - Remote hosts behind the default gateway had always been redirected to a different gateway. A rtable/dst_entry will be added for that host. Making more dst_entrys with lower reference counts. Making this more probable. - All vmcores showed a postitive LockDroppedIcmps value, e.g: LockDroppedIcmps 267 A closer look at the tcp_v4_err() handler revealed that do_redirect() will run regardless of whether user space has the socket locked. This can result in a race condition where the same dst_entry cached in sk->sk_dst_entry can be decremented twice for the same socket via: do_redirect()->__sk_dst_check()-> dst_release(). Which leads to the dst_entry being prematurely freed with another socket pointing to it via sk->sk_dst_cache and a subsequent crash. To fix this skip do_redirect() if usespace has the socket locked. Instead let the redirect take place later when user space does not have the socket locked. The dccp/IPv6 code is very similar in this respect, so fixing it there too. As Eric Garver pointed out the following commit now invalidates routes. Which can set the dst->obsolete flag so that ipv4_dst_check() returns null and triggers the dst_release(). Fixes: ceb3320 ("ipv4: Kill routes during PMTU/redirect updates.") Cc: Eric Garver <egarver@redhat.com> Cc: Hannes Sowa <hsowa@redhat.com> Signed-off-by: Jon Maxwell <jmaxwell37@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Dmitry reported a lockdep splat [1] (false positive) that we can fix by releasing the spinlock before calling icmp_send() from ip_expire() This is a false positive because sending an ICMP message can not possibly re-enter the IP frag engine. [1] [ INFO: possible circular locking dependency detected ] 4.10.0+ #29 Not tainted ------------------------------------------------------- modprobe/12392 is trying to acquire lock: (_xmit_ETHER#2){+.-...}, at: [<ffffffff837a8182>] spin_lock include/linux/spinlock.h:299 [inline] (_xmit_ETHER#2){+.-...}, at: [<ffffffff837a8182>] __netif_tx_lock include/linux/netdevice.h:3486 [inline] (_xmit_ETHER#2){+.-...}, at: [<ffffffff837a8182>] sch_direct_xmit+0x282/0x6d0 net/sched/sch_generic.c:180 but task is already holding lock: (&(&q->lock)->rlock){+.-...}, at: [<ffffffff8389a4d1>] spin_lock include/linux/spinlock.h:299 [inline] (&(&q->lock)->rlock){+.-...}, at: [<ffffffff8389a4d1>] ip_expire+0x51/0x6c0 net/ipv4/ip_fragment.c:201 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #1 (&(&q->lock)->rlock){+.-...}: validate_chain kernel/locking/lockdep.c:2267 [inline] __lock_acquire+0x2149/0x3430 kernel/locking/lockdep.c:3340 lock_acquire+0x2a1/0x630 kernel/locking/lockdep.c:3755 __raw_spin_lock include/linux/spinlock_api_smp.h:142 [inline] _raw_spin_lock+0x33/0x50 kernel/locking/spinlock.c:151 spin_lock include/linux/spinlock.h:299 [inline] ip_defrag+0x3a2/0x4130 net/ipv4/ip_fragment.c:669 ip_check_defrag+0x4e3/0x8b0 net/ipv4/ip_fragment.c:713 packet_rcv_fanout+0x282/0x800 net/packet/af_packet.c:1459 deliver_skb net/core/dev.c:1834 [inline] dev_queue_xmit_nit+0x294/0xa90 net/core/dev.c:1890 xmit_one net/core/dev.c:2903 [inline] dev_hard_start_xmit+0x16b/0xab0 net/core/dev.c:2923 sch_direct_xmit+0x31f/0x6d0 net/sched/sch_generic.c:182 __dev_xmit_skb net/core/dev.c:3092 [inline] __dev_queue_xmit+0x13e5/0x1e60 net/core/dev.c:3358 dev_queue_xmit+0x17/0x20 net/core/dev.c:3423 neigh_resolve_output+0x6b9/0xb10 net/core/neighbour.c:1308 neigh_output include/net/neighbour.h:478 [inline] ip_finish_output2+0x8b8/0x15a0 net/ipv4/ip_output.c:228 ip_do_fragment+0x1d93/0x2720 net/ipv4/ip_output.c:672 ip_fragment.constprop.54+0x145/0x200 net/ipv4/ip_output.c:545 ip_finish_output+0x82d/0xe10 net/ipv4/ip_output.c:314 NF_HOOK_COND include/linux/netfilter.h:246 [inline] ip_output+0x1f0/0x7a0 net/ipv4/ip_output.c:404 dst_output include/net/dst.h:486 [inline] ip_local_out+0x95/0x170 net/ipv4/ip_output.c:124 ip_send_skb+0x3c/0xc0 net/ipv4/ip_output.c:1492 ip_push_pending_frames+0x64/0x80 net/ipv4/ip_output.c:1512 raw_sendmsg+0x26de/0x3a00 net/ipv4/raw.c:655 inet_sendmsg+0x164/0x5b0 net/ipv4/af_inet.c:761 sock_sendmsg_nosec net/socket.c:633 [inline] sock_sendmsg+0xca/0x110 net/socket.c:643 ___sys_sendmsg+0x4a3/0x9f0 net/socket.c:1985 __sys_sendmmsg+0x25c/0x750 net/socket.c:2075 SYSC_sendmmsg net/socket.c:2106 [inline] SyS_sendmmsg+0x35/0x60 net/socket.c:2101 do_syscall_64+0x2e8/0x930 arch/x86/entry/common.c:281 return_from_SYSCALL_64+0x0/0x7a -> #0 (_xmit_ETHER#2){+.-...}: check_prev_add kernel/locking/lockdep.c:1830 [inline] check_prevs_add+0xa8f/0x19f0 kernel/locking/lockdep.c:1940 validate_chain kernel/locking/lockdep.c:2267 [inline] __lock_acquire+0x2149/0x3430 kernel/locking/lockdep.c:3340 lock_acquire+0x2a1/0x630 kernel/locking/lockdep.c:3755 __raw_spin_lock include/linux/spinlock_api_smp.h:142 [inline] _raw_spin_lock+0x33/0x50 kernel/locking/spinlock.c:151 spin_lock include/linux/spinlock.h:299 [inline] __netif_tx_lock include/linux/netdevice.h:3486 [inline] sch_direct_xmit+0x282/0x6d0 net/sched/sch_generic.c:180 __dev_xmit_skb net/core/dev.c:3092 [inline] __dev_queue_xmit+0x13e5/0x1e60 net/core/dev.c:3358 dev_queue_xmit+0x17/0x20 net/core/dev.c:3423 neigh_hh_output include/net/neighbour.h:468 [inline] neigh_output include/net/neighbour.h:476 [inline] ip_finish_output2+0xf6c/0x15a0 net/ipv4/ip_output.c:228 ip_finish_output+0xa29/0xe10 net/ipv4/ip_output.c:316 NF_HOOK_COND include/linux/netfilter.h:246 [inline] ip_output+0x1f0/0x7a0 net/ipv4/ip_output.c:404 dst_output include/net/dst.h:486 [inline] ip_local_out+0x95/0x170 net/ipv4/ip_output.c:124 ip_send_skb+0x3c/0xc0 net/ipv4/ip_output.c:1492 ip_push_pending_frames+0x64/0x80 net/ipv4/ip_output.c:1512 icmp_push_reply+0x372/0x4d0 net/ipv4/icmp.c:394 icmp_send+0x156c/0x1c80 net/ipv4/icmp.c:754 ip_expire+0x40e/0x6c0 net/ipv4/ip_fragment.c:239 call_timer_fn+0x241/0x820 kernel/time/timer.c:1268 expire_timers kernel/time/timer.c:1307 [inline] __run_timers+0x960/0xcf0 kernel/time/timer.c:1601 run_timer_softirq+0x21/0x80 kernel/time/timer.c:1614 __do_softirq+0x31f/0xbe7 kernel/softirq.c:284 invoke_softirq kernel/softirq.c:364 [inline] irq_exit+0x1cc/0x200 kernel/softirq.c:405 exiting_irq arch/x86/include/asm/apic.h:657 [inline] smp_apic_timer_interrupt+0x76/0xa0 arch/x86/kernel/apic/apic.c:962 apic_timer_interrupt+0x93/0xa0 arch/x86/entry/entry_64.S:707 __read_once_size include/linux/compiler.h:254 [inline] atomic_read arch/x86/include/asm/atomic.h:26 [inline] rcu_dynticks_curr_cpu_in_eqs kernel/rcu/tree.c:350 [inline] __rcu_is_watching kernel/rcu/tree.c:1133 [inline] rcu_is_watching+0x83/0x110 kernel/rcu/tree.c:1147 rcu_read_lock_held+0x87/0xc0 kernel/rcu/update.c:293 radix_tree_deref_slot include/linux/radix-tree.h:238 [inline] filemap_map_pages+0x6d4/0x1570 mm/filemap.c:2335 do_fault_around mm/memory.c:3231 [inline] do_read_fault mm/memory.c:3265 [inline] do_fault+0xbd5/0x2080 mm/memory.c:3370 handle_pte_fault mm/memory.c:3600 [inline] __handle_mm_fault+0x1062/0x2cb0 mm/memory.c:3714 handle_mm_fault+0x1e2/0x480 mm/memory.c:3751 __do_page_fault+0x4f6/0xb60 arch/x86/mm/fault.c:1397 do_page_fault+0x54/0x70 arch/x86/mm/fault.c:1460 page_fault+0x28/0x30 arch/x86/entry/entry_64.S:1011 other info that might help us debug this: Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(&(&q->lock)->rlock); lock(_xmit_ETHER#2); lock(&(&q->lock)->rlock); lock(_xmit_ETHER#2); *** DEADLOCK *** 10 locks held by modprobe/12392: #0: (&mm->mmap_sem){++++++}, at: [<ffffffff81329758>] __do_page_fault+0x2b8/0xb60 arch/x86/mm/fault.c:1336 #1: (rcu_read_lock){......}, at: [<ffffffff8188cab6>] filemap_map_pages+0x1e6/0x1570 mm/filemap.c:2324 #2: (&(ptlock_ptr(page))->rlock#2){+.+...}, at: [<ffffffff81984a78>] spin_lock include/linux/spinlock.h:299 [inline] #2: (&(ptlock_ptr(page))->rlock#2){+.+...}, at: [<ffffffff81984a78>] pte_alloc_one_map mm/memory.c:2944 [inline] #2: (&(ptlock_ptr(page))->rlock#2){+.+...}, at: [<ffffffff81984a78>] alloc_set_pte+0x13b8/0x1b90 mm/memory.c:3072 #3: (((&q->timer))){+.-...}, at: [<ffffffff81627e72>] lockdep_copy_map include/linux/lockdep.h:175 [inline] #3: (((&q->timer))){+.-...}, at: [<ffffffff81627e72>] call_timer_fn+0x1c2/0x820 kernel/time/timer.c:1258 #4: (&(&q->lock)->rlock){+.-...}, at: [<ffffffff8389a4d1>] spin_lock include/linux/spinlock.h:299 [inline] #4: (&(&q->lock)->rlock){+.-...}, at: [<ffffffff8389a4d1>] ip_expire+0x51/0x6c0 net/ipv4/ip_fragment.c:201 #5: (rcu_read_lock){......}, at: [<ffffffff8389a633>] ip_expire+0x1b3/0x6c0 net/ipv4/ip_fragment.c:216 #6: (slock-AF_INET){+.-...}, at: [<ffffffff839b3313>] spin_trylock include/linux/spinlock.h:309 [inline] #6: (slock-AF_INET){+.-...}, at: [<ffffffff839b3313>] icmp_xmit_lock net/ipv4/icmp.c:219 [inline] #6: (slock-AF_INET){+.-...}, at: [<ffffffff839b3313>] icmp_send+0x803/0x1c80 net/ipv4/icmp.c:681 #7: (rcu_read_lock_bh){......}, at: [<ffffffff838ab9a1>] ip_finish_output2+0x2c1/0x15a0 net/ipv4/ip_output.c:198 #8: (rcu_read_lock_bh){......}, at: [<ffffffff836d1dee>] __dev_queue_xmit+0x23e/0x1e60 net/core/dev.c:3324 #9: (dev->qdisc_running_key ?: &qdisc_running_key){+.....}, at: [<ffffffff836d3a27>] dev_queue_xmit+0x17/0x20 net/core/dev.c:3423 stack backtrace: CPU: 0 PID: 12392 Comm: modprobe Not tainted 4.10.0+ #29 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: <IRQ> __dump_stack lib/dump_stack.c:16 [inline] dump_stack+0x2ee/0x3ef lib/dump_stack.c:52 print_circular_bug+0x307/0x3b0 kernel/locking/lockdep.c:1204 check_prev_add kernel/locking/lockdep.c:1830 [inline] check_prevs_add+0xa8f/0x19f0 kernel/locking/lockdep.c:1940 validate_chain kernel/locking/lockdep.c:2267 [inline] __lock_acquire+0x2149/0x3430 kernel/locking/lockdep.c:3340 lock_acquire+0x2a1/0x630 kernel/locking/lockdep.c:3755 __raw_spin_lock include/linux/spinlock_api_smp.h:142 [inline] _raw_spin_lock+0x33/0x50 kernel/locking/spinlock.c:151 spin_lock include/linux/spinlock.h:299 [inline] __netif_tx_lock include/linux/netdevice.h:3486 [inline] sch_direct_xmit+0x282/0x6d0 net/sched/sch_generic.c:180 __dev_xmit_skb net/core/dev.c:3092 [inline] __dev_queue_xmit+0x13e5/0x1e60 net/core/dev.c:3358 dev_queue_xmit+0x17/0x20 net/core/dev.c:3423 neigh_hh_output include/net/neighbour.h:468 [inline] neigh_output include/net/neighbour.h:476 [inline] ip_finish_output2+0xf6c/0x15a0 net/ipv4/ip_output.c:228 ip_finish_output+0xa29/0xe10 net/ipv4/ip_output.c:316 NF_HOOK_COND include/linux/netfilter.h:246 [inline] ip_output+0x1f0/0x7a0 net/ipv4/ip_output.c:404 dst_output include/net/dst.h:486 [inline] ip_local_out+0x95/0x170 net/ipv4/ip_output.c:124 ip_send_skb+0x3c/0xc0 net/ipv4/ip_output.c:1492 ip_push_pending_frames+0x64/0x80 net/ipv4/ip_output.c:1512 icmp_push_reply+0x372/0x4d0 net/ipv4/icmp.c:394 icmp_send+0x156c/0x1c80 net/ipv4/icmp.c:754 ip_expire+0x40e/0x6c0 net/ipv4/ip_fragment.c:239 call_timer_fn+0x241/0x820 kernel/time/timer.c:1268 expire_timers kernel/time/timer.c:1307 [inline] __run_timers+0x960/0xcf0 kernel/time/timer.c:1601 run_timer_softirq+0x21/0x80 kernel/time/timer.c:1614 __do_softirq+0x31f/0xbe7 kernel/softirq.c:284 invoke_softirq kernel/softirq.c:364 [inline] irq_exit+0x1cc/0x200 kernel/softirq.c:405 exiting_irq arch/x86/include/asm/apic.h:657 [inline] smp_apic_timer_interrupt+0x76/0xa0 arch/x86/kernel/apic/apic.c:962 apic_timer_interrupt+0x93/0xa0 arch/x86/entry/entry_64.S:707 RIP: 0010:__read_once_size include/linux/compiler.h:254 [inline] RIP: 0010:atomic_read arch/x86/include/asm/atomic.h:26 [inline] RIP: 0010:rcu_dynticks_curr_cpu_in_eqs kernel/rcu/tree.c:350 [inline] RIP: 0010:__rcu_is_watching kernel/rcu/tree.c:1133 [inline] RIP: 0010:rcu_is_watching+0x83/0x110 kernel/rcu/tree.c:1147 RSP: 0000:ffff8801c391f120 EFLAGS: 00000a03 ORIG_RAX: ffffffffffffff10 RAX: dffffc0000000000 RBX: ffff8801c391f148 RCX: 0000000000000000 RDX: 0000000000000000 RSI: 000055edd4374000 RDI: ffff8801dbe1ae0c RBP: ffff8801c391f1a0 R08: 0000000000000002 R09: 0000000000000000 R10: dffffc0000000000 R11: 0000000000000002 R12: 1ffff10038723e25 R13: ffff8801dbe1ae00 R14: ffff8801c391f680 R15: dffffc0000000000 </IRQ> rcu_read_lock_held+0x87/0xc0 kernel/rcu/update.c:293 radix_tree_deref_slot include/linux/radix-tree.h:238 [inline] filemap_map_pages+0x6d4/0x1570 mm/filemap.c:2335 do_fault_around mm/memory.c:3231 [inline] do_read_fault mm/memory.c:3265 [inline] do_fault+0xbd5/0x2080 mm/memory.c:3370 handle_pte_fault mm/memory.c:3600 [inline] __handle_mm_fault+0x1062/0x2cb0 mm/memory.c:3714 handle_mm_fault+0x1e2/0x480 mm/memory.c:3751 __do_page_fault+0x4f6/0xb60 arch/x86/mm/fault.c:1397 do_page_fault+0x54/0x70 arch/x86/mm/fault.c:1460 page_fault+0x28/0x30 arch/x86/entry/entry_64.S:1011 RIP: 0033:0x7f83172f2786 RSP: 002b:00007fffe859ae80 EFLAGS: 00010293 RAX: 000055edd4373040 RBX: 00007f83175111c8 RCX: 000055edd4373238 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 00007f8317510970 RBP: 00007fffe859afd0 R08: 0000000000000009 R09: 0000000000000000 R10: 0000000000000064 R11: 0000000000000000 R12: 000055edd4373040 R13: 0000000000000000 R14: 00007fffe859afe8 R15: 0000000000000000 Signed-off-by: Eric Dumazet <edumazet@google.com> Reported-by: Dmitry Vyukov <dvyukov@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>

Our chosen ic_dev may be anywhere in our list of ic_devs, and we may free it before attempting to close others. When we compare d->dev and ic_dev->dev, we're potentially dereferencing memory returned to the allocator. This causes KASAN to scream for each subsequent ic_dev we check. As there's a 1-1 mapping between ic_devs and netdevs, we can instead compare d and ic_dev directly, which implicitly handles the !ic_dev case, and avoids the use-after-free. The ic_dev pointer may be stale, but we will not dereference it. Original splat: [ 6.487446] ================================================================== [ 6.494693] BUG: KASAN: use-after-free in ic_close_devs+0xc4/0x154 at addr ffff800367efa708 [ 6.503013] Read of size 8 by task swapper/0/1 [ 6.507452] CPU: 5 PID: 1 Comm: swapper/0 Not tainted 4.11.0-rc3-00002-gda42158 #8 [ 6.514993] Hardware name: AppliedMicro Mustang/Mustang, BIOS 3.05.05-beta_rc Jan 27 2016 [ 6.523138] Call trace: [ 6.525590] [<ffff200008094778>] dump_backtrace+0x0/0x570 [ 6.530976] [<ffff200008094d08>] show_stack+0x20/0x30 [ 6.536017] [<ffff200008bee928>] dump_stack+0x120/0x188 [ 6.541231] [<ffff20000856d5e4>] kasan_object_err+0x24/0xa0 [ 6.546790] [<ffff20000856d924>] kasan_report_error+0x244/0x738 [ 6.552695] [<ffff20000856dfec>] __asan_report_load8_noabort+0x54/0x80 [ 6.559204] [<ffff20000aae86ac>] ic_close_devs+0xc4/0x154 [ 6.564590] [<ffff20000aaedbac>] ip_auto_config+0x2ed4/0x2f1c [ 6.570321] [<ffff200008084b04>] do_one_initcall+0xcc/0x370 [ 6.575882] [<ffff20000aa31de8>] kernel_init_freeable+0x5f8/0x6c4 [ 6.581959] [<ffff20000a16df00>] kernel_init+0x18/0x190 [ 6.587171] [<ffff200008084710>] ret_from_fork+0x10/0x40 [ 6.592468] Object at ffff800367efa700, in cache kmalloc-128 size: 128 [ 6.598969] Allocated: [ 6.601324] PID = 1 [ 6.603427] save_stack_trace_tsk+0x0/0x418 [ 6.607603] save_stack_trace+0x20/0x30 [ 6.611430] kasan_kmalloc+0xd8/0x188 [ 6.615087] ip_auto_config+0x8c4/0x2f1c [ 6.619002] do_one_initcall+0xcc/0x370 [ 6.622832] kernel_init_freeable+0x5f8/0x6c4 [ 6.627178] kernel_init+0x18/0x190 [ 6.630660] ret_from_fork+0x10/0x40 [ 6.634223] Freed: [ 6.636233] PID = 1 [ 6.638334] save_stack_trace_tsk+0x0/0x418 [ 6.642510] save_stack_trace+0x20/0x30 [ 6.646337] kasan_slab_free+0x88/0x178 [ 6.650167] kfree+0xb8/0x478 [ 6.653131] ic_close_devs+0x130/0x154 [ 6.656875] ip_auto_config+0x2ed4/0x2f1c [ 6.660875] do_one_initcall+0xcc/0x370 [ 6.664705] kernel_init_freeable+0x5f8/0x6c4 [ 6.669051] kernel_init+0x18/0x190 [ 6.672534] ret_from_fork+0x10/0x40 [ 6.676098] Memory state around the buggy address: [ 6.680880] ffff800367efa600: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 [ 6.688078] ffff800367efa680: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc [ 6.695276] >ffff800367efa700: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 6.702469] ^ [ 6.705952] ffff800367efa780: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc [ 6.713149] ffff800367efa800: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 6.720343] ================================================================== [ 6.727536] Disabling lock debugging due to kernel taint Signed-off-by: Mark Rutland <mark.rutland@arm.com> Cc: Alexey Kuznetsov <kuznet@ms2.inr.ac.ru> Cc: David S. Miller <davem@davemloft.net> Cc: Hideaki YOSHIFUJI <yoshfuji@linux-ipv6.org> Cc: James Morris <jmorris@namei.org> Cc: Patrick McHardy <kaber@trash.net> Cc: netdev@vger.kernel.org Signed-off-by: David S. Miller <davem@davemloft.net>

We have several places across the kernel where we want to access another task's syscall arguments, such as ptrace(2), seccomp(2), etc., by making a call to syscall_get_arguments(). This works for register arguments right away by accessing the task's `regs' member of `struct pt_regs', however for stack arguments seen with 32-bit/o32 kernels things are more complicated. Technically they ought to be obtained from the user stack with calls to an access_remote_vm(), but we have an easier way available already. So as to be able to access syscall stack arguments as regular function arguments following the MIPS calling convention we copy them over from the user stack to the kernel stack in arch/mips/kernel/scall32-o32.S, in handle_sys(), to the current stack frame's outgoing argument space at the top of the stack, which is where the handler called expects to see its incoming arguments. This area is also pointed at by the `pt_regs' pointer obtained by task_pt_regs(). Make the o32 stack argument space a proper member of `struct pt_regs' then, by renaming the existing member from `pad0' to `args' and using generated offsets to access the space. No functional change though. With the change in place the o32 kernel stack frame layout at the entry to a syscall handler invoked by handle_sys() is therefore as follows: $sp + 68 -> | ... | <- pt_regs.regs[9] +---------------------+ $sp + 64 -> | $t0 | <- pt_regs.regs[8] +---------------------+ $sp + 60 -> | $a3/argument #4 | <- pt_regs.regs[7] +---------------------+ $sp + 56 -> | $a2/argument #3 | <- pt_regs.regs[6] +---------------------+ $sp + 52 -> | $a1/argument #2 | <- pt_regs.regs[5] +---------------------+ $sp + 48 -> | $a0/argument #1 | <- pt_regs.regs[4] +---------------------+ $sp + 44 -> | $v1 | <- pt_regs.regs[3] +---------------------+ $sp + 40 -> | $v0 | <- pt_regs.regs[2] +---------------------+ $sp + 36 -> | $at | <- pt_regs.regs[1] +---------------------+ $sp + 32 -> | $zero | <- pt_regs.regs[0] +---------------------+ $sp + 28 -> | stack argument #8 | <- pt_regs.args[7] +---------------------+ $sp + 24 -> | stack argument #7 | <- pt_regs.args[6] +---------------------+ $sp + 20 -> | stack argument #6 | <- pt_regs.args[5] +---------------------+ $sp + 16 -> | stack argument #5 | <- pt_regs.args[4] +---------------------+ $sp + 12 -> | psABI space for $a3 | <- pt_regs.args[3] +---------------------+ $sp + 8 -> | psABI space for $a2 | <- pt_regs.args[2] +---------------------+ $sp + 4 -> | psABI space for $a1 | <- pt_regs.args[1] +---------------------+ $sp + 0 -> | psABI space for $a0 | <- pt_regs.args[0] +---------------------+ holding user data received and with the first 4 frame slots reserved by the psABI for the compiler to spill the incoming arguments from $a0-$a3 registers (which it sometimes does according to its needs) and the next 4 frame slots designated by the psABI for any stack function arguments that follow. This data is also available for other tasks to peek/poke at as reqired and where permitted. Signed-off-by: Maciej W. Rozycki <macro@orcam.me.uk> Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>

This makes ptrace/get_syscall_info selftest pass on mips o32 and mips64 o32 by fixing the following two test assertions: 1. get_syscall_info test assertion on mips o32: # get_syscall_info.c:218:get_syscall_info:Expected exp_args[5] (3134521044) == info.entry.args[4] (4911432) # get_syscall_info.c:219:get_syscall_info:wait #1: entry stop mismatch 2. get_syscall_info test assertion on mips64 o32: # get_syscall_info.c:209:get_syscall_info:Expected exp_args[2] (3134324433) == info.entry.args[1] (18446744072548908753) # get_syscall_info.c:210:get_syscall_info:wait #1: entry stop mismatch The first assertion happens due to mips_get_syscall_arg() trying to access another task's context but failing to do it properly because get_user() it calls just peeks at the current task's context. It usually does not crash because the default user stack always gets assigned the same VMA, but it is pure luck which mips_get_syscall_arg() wouldn't have if e.g. the stack was switched (via setcontext(3) or however) or a non-default process's thread peeked at, and in any case irrelevant data is obtained just as observed with the test case. mips_get_syscall_arg() ought to be using access_remote_vm() instead to retrieve the other task's stack contents, but given that the data has been already obtained and saved in `struct pt_regs' it would be an overkill. The first assertion is fixed for mips o32 by using struct pt_regs.args instead of get_user() to obtain syscall arguments. This approach works due to this piece in arch/mips/kernel/scall32-o32.S: /* * Ok, copy the args from the luser stack to the kernel stack. */ .set push .set noreorder .set nomacro load_a4: user_lw(t5, 16(t0)) # argument #5 from usp load_a5: user_lw(t6, 20(t0)) # argument #6 from usp load_a6: user_lw(t7, 24(t0)) # argument #7 from usp load_a7: user_lw(t8, 28(t0)) # argument #8 from usp loads_done: sw t5, PT_ARG4(sp) # argument #5 to ksp sw t6, PT_ARG5(sp) # argument #6 to ksp sw t7, PT_ARG6(sp) # argument #7 to ksp sw t8, PT_ARG7(sp) # argument #8 to ksp .set pop .section __ex_table,"a" PTR_WD load_a4, bad_stack_a4 PTR_WD load_a5, bad_stack_a5 PTR_WD load_a6, bad_stack_a6 PTR_WD load_a7, bad_stack_a7 .previous arch/mips/kernel/scall64-o32.S has analogous code for mips64 o32 that allows fixing the issue by obtaining syscall arguments from struct pt_regs.regs[4..11] instead of the erroneous use of get_user(). The second assertion is fixed by truncating 64-bit values to 32-bit syscall arguments. Fixes: c0ff3c5 ("MIPS: Enable HAVE_ARCH_TRACEHOOK.") Signed-off-by: Dmitry V. Levin <ldv@strace.io> Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>

KMSAN reported a use-after-free issue in eth_skb_pkt_type()[1]. The cause of the issue was that eth_skb_pkt_type() accessed skb's data that didn't contain an Ethernet header. This occurs when bpf_prog_test_run_xdp() passes an invalid value as the user_data argument to bpf_test_init(). Fix this by returning an error when user_data is less than ETH_HLEN in bpf_test_init(). Additionally, remove the check for "if (user_size > size)" as it is unnecessary. [1] BUG: KMSAN: use-after-free in eth_skb_pkt_type include/linux/etherdevice.h:627 [inline] BUG: KMSAN: use-after-free in eth_type_trans+0x4ee/0x980 net/ethernet/eth.c:165 eth_skb_pkt_type include/linux/etherdevice.h:627 [inline] eth_type_trans+0x4ee/0x980 net/ethernet/eth.c:165 __xdp_build_skb_from_frame+0x5a8/0xa50 net/core/xdp.c:635 xdp_recv_frames net/bpf/test_run.c:272 [inline] xdp_test_run_batch net/bpf/test_run.c:361 [inline] bpf_test_run_xdp_live+0x2954/0x3330 net/bpf/test_run.c:390 bpf_prog_test_run_xdp+0x148e/0x1b10 net/bpf/test_run.c:1318 bpf_prog_test_run+0x5b7/0xa30 kernel/bpf/syscall.c:4371 __sys_bpf+0x6a6/0xe20 kernel/bpf/syscall.c:5777 __do_sys_bpf kernel/bpf/syscall.c:5866 [inline] __se_sys_bpf kernel/bpf/syscall.c:5864 [inline] __x64_sys_bpf+0xa4/0xf0 kernel/bpf/syscall.c:5864 x64_sys_call+0x2ea0/0x3d90 arch/x86/include/generated/asm/syscalls_64.h:322 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xd9/0x1d0 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f Uninit was created at: free_pages_prepare mm/page_alloc.c:1056 [inline] free_unref_page+0x156/0x1320 mm/page_alloc.c:2657 __free_pages+0xa3/0x1b0 mm/page_alloc.c:4838 bpf_ringbuf_free kernel/bpf/ringbuf.c:226 [inline] ringbuf_map_free+0xff/0x1e0 kernel/bpf/ringbuf.c:235 bpf_map_free kernel/bpf/syscall.c:838 [inline] bpf_map_free_deferred+0x17c/0x310 kernel/bpf/syscall.c:862 process_one_work kernel/workqueue.c:3229 [inline] process_scheduled_works+0xa2b/0x1b60 kernel/workqueue.c:3310 worker_thread+0xedf/0x1550 kernel/workqueue.c:3391 kthread+0x535/0x6b0 kernel/kthread.c:389 ret_from_fork+0x6e/0x90 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 CPU: 1 UID: 0 PID: 17276 Comm: syz.1.16450 Not tainted 6.12.0-05490-g9bb88c659673 #8 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.16.3-3.fc41 04/01/2014 Fixes: be3d72a ("bpf: move user_size out of bpf_test_init") Reported-by: syzkaller <syzkaller@googlegroups.com> Suggested-by: Martin KaFai Lau <martin.lau@linux.dev> Signed-off-by: Shigeru Yoshida <syoshida@redhat.com> Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org> Acked-by: Stanislav Fomichev <sdf@fomichev.me> Acked-by: Daniel Borkmann <daniel@iogearbox.net> Link: https://patch.msgid.link/20250121150643.671650-1-syoshida@redhat.com Signed-off-by: Alexei Starovoitov <ast@kernel.org>

napi_schedule() is expected to be called either: * From an interrupt, where raised softirqs are handled on IRQ exit * From a softirq disabled section, where raised softirqs are handled on the next call to local_bh_enable(). * From a softirq handler, where raised softirqs are handled on the next round in do_softirq(), or further deferred to a dedicated kthread. Other bare tasks context may end up ignoring the raised NET_RX vector until the next random softirq handling opportunity, which may not happen before a while if the CPU goes idle afterwards with the tick stopped. Such "misuses" have been detected on several places thanks to messages of the kind: "NOHZ tick-stop error: local softirq work is pending, handler #8!!!" For example: __raise_softirq_irqoff __napi_schedule rtl8152_runtime_resume.isra.0 rtl8152_resume usb_resume_interface.isra.0 usb_resume_both __rpm_callback rpm_callback rpm_resume __pm_runtime_resume usb_autoresume_device usb_remote_wakeup hub_event process_one_work worker_thread kthread ret_from_fork ret_from_fork_asm And also: * drivers/net/usb/r8152.c::rtl_work_func_t * drivers/net/netdevsim/netdev.c::nsim_start_xmit There is a long history of issues of this kind: 019edd0 ("ath10k: sdio: Add missing BH locking around napi_schdule()") 3300685 ("idpf: disable local BH when scheduling napi for marker packets") e3d5d70 ("net: lan78xx: fix "softirq work is pending" error") e55c27e ("mt76: mt7615: add missing bh-disable around rx napi schedule") c0182aa ("mt76: mt7915: add missing bh-disable around tx napi enable/schedule") 970be1d ("mt76: disable BH around napi_schedule() calls") 019edd0 ("ath10k: sdio: Add missing BH locking around napi_schdule()") 30bfec4 ("can: rx-offload: can_rx_offload_threaded_irq_finish(): add new function to be called from threaded interrupt") e63052a ("mlx5e: add add missing BH locking around napi_schdule()") 83a0c6e ("i40e: Invoke softirqs after napi_reschedule") bd4ce94 ("mlx4: Invoke softirqs after napi_reschedule") 8cf699e ("mlx4: do not call napi_schedule() without care") ec13ee8 ("virtio_net: invoke softirqs after __napi_schedule") This shows that relying on the caller to arrange a proper context for the softirqs to be handled while calling napi_schedule() is very fragile and error prone. Also fixing them can also prove challenging if the caller may be called from different kinds of contexts. Therefore fix this from napi_schedule() itself with waking up ksoftirqd when softirqs are raised from task contexts. Reported-by: Paul Menzel <pmenzel@molgen.mpg.de> Reported-by: Jakub Kicinski <kuba@kernel.org> Reported-by: Francois Romieu <romieu@fr.zoreil.com> Closes: https://lore.kernel.org/lkml/354a2690-9bbf-4ccb-8769-fa94707a9340@molgen.mpg.de/ Cc: Breno Leitao <leitao@debian.org> Signed-off-by: Frederic Weisbecker <frederic@kernel.org> Reviewed-by: Eric Dumazet <edumazet@google.com> Link: https://patch.msgid.link/20250223221708.27130-1-frederic@kernel.org Signed-off-by: Jakub Kicinski <kuba@kernel.org>

Chia-Yu Chang says: ==================== AccECN protocol preparation patch series Please find the v7 v7 (03-Mar-2025) - Move 2 new patches added in v6 to the next AccECN patch series v6 (27-Dec-2024) - Avoid removing removing the potential CA_ACK_WIN_UPDATE in ack_ev_flags of patch #1 (Eric Dumazet <edumazet@google.com>) - Add reviewed-by tag in patches #2, #3, #4, #5, #6, #7, #8, #12, #14 - Foloiwng 2 new pathces are added after patch #9 (Patch that adds SKB_GSO_TCP_ACCECN) * New patch #10 to replace exisiting SKB_GSO_TCP_ECN with SKB_GSO_TCP_ACCECN in the driver to avoid CWR flag corruption * New patch #11 adds AccECN for virtio by adding new negotiation flag (VIRTIO_NET_F_HOST/GUEST_ACCECN) in feature handshake and translating Accurate ECN GSO flag between virtio_net_hdr (VIRTIO_NET_HDR_GSO_ACCECN) and skb header (SKB_GSO_TCP_ACCECN) - Add detailed changelog and comments in #13 (Eric Dumazet <edumazet@google.com>) - Move patch #14 to the next AccECN patch series (Eric Dumazet <edumazet@google.com>) v5 (5-Nov-2024) - Add helper function "tcp_flags_ntohs" to preserve last 2 bytes of TCP flags of patch #4 (Paolo Abeni <pabeni@redhat.com>) - Fix reverse X-max tree order of patches #4, #11 (Paolo Abeni <pabeni@redhat.com>) - Rename variable "delta" as "timestamp_delta" of patch #2 fo clariety - Remove patch #14 in this series (Paolo Abeni <pabeni@redhat.com>, Joel Granados <joel.granados@kernel.org>) v4 (21-Oct-2024) - Fix line length warning of patches #2, #4, #8, #10, #11, #14 - Fix spaces preferred around '|' (ctx:VxV) warning of patch #7 - Add missing CC'ed of patches #4, #12, #14 v3 (19-Oct-2024) - Fix build error in v2 v2 (18-Oct-2024) - Fix warning caused by NETIF_F_GSO_ACCECN_BIT in patch #9 (Jakub Kicinski <kuba@kernel.org>) The full patch series can be found in https://github.com/L4STeam/linux-net-next/commits/upstream_l4steam/ The Accurate ECN draft can be found in https://datatracker.ietf.org/doc/html/draft-ietf-tcpm-accurate-ecn-28 ==================== Signed-off-by: David S. Miller <davem@davemloft.net>

perf test 11 hwmon fails on s390 with this error # ./perf test -Fv 11 --- start --- ---- end ---- 11.1: Basic parsing test : Ok --- start --- Testing 'temp_test_hwmon_event1' Using CPUID IBM,3931,704,A01,3.7,002f temp_test_hwmon_event1 -> hwmon_a_test_hwmon_pmu/temp_test_hwmon_event1/ FAILED tests/hwmon_pmu.c:189 Unexpected config for 'temp_test_hwmon_event1', 292470092988416 != 655361 ---- end ---- 11.2: Parsing without PMU name : FAILED! --- start --- Testing 'hwmon_a_test_hwmon_pmu/temp_test_hwmon_event1/' FAILED tests/hwmon_pmu.c:189 Unexpected config for 'hwmon_a_test_hwmon_pmu/temp_test_hwmon_event1/', 292470092988416 != 655361 ---- end ---- 11.3: Parsing with PMU name : FAILED! # The root cause is in member test_event::config which is initialized to 0xA0001 or 655361. During event parsing a long list event parsing functions are called and end up with this gdb call stack: #0 hwmon_pmu__config_term (hwm=0x168dfd0, attr=0x3ffffff5ee8, term=0x168db60, err=0x3ffffff81c8) at util/hwmon_pmu.c:623 #1 hwmon_pmu__config_terms (pmu=0x168dfd0, attr=0x3ffffff5ee8, terms=0x3ffffff5ea8, err=0x3ffffff81c8) at util/hwmon_pmu.c:662 #2 0x00000000012f870c in perf_pmu__config_terms (pmu=0x168dfd0, attr=0x3ffffff5ee8, terms=0x3ffffff5ea8, zero=false, apply_hardcoded=false, err=0x3ffffff81c8) at util/pmu.c:1519 #3 0x00000000012f88a4 in perf_pmu__config (pmu=0x168dfd0, attr=0x3ffffff5ee8, head_terms=0x3ffffff5ea8, apply_hardcoded=false, err=0x3ffffff81c8) at util/pmu.c:1545 #4 0x00000000012680c4 in parse_events_add_pmu (parse_state=0x3ffffff7fb8, list=0x168dc00, pmu=0x168dfd0, const_parsed_terms=0x3ffffff6090, auto_merge_stats=true, alternate_hw_config=10) at util/parse-events.c:1508 #5 0x00000000012684c6 in parse_events_multi_pmu_add (parse_state=0x3ffffff7fb8, event_name=0x168ec10 "temp_test_hwmon_event1", hw_config=10, const_parsed_terms=0x0, listp=0x3ffffff6230, loc_=0x3ffffff70e0) at util/parse-events.c:1592 #6 0x00000000012f0e4e in parse_events_parse (_parse_state=0x3ffffff7fb8, scanner=0x16878c0) at util/parse-events.y:293 #7 0x00000000012695a0 in parse_events__scanner (str=0x3ffffff81d8 "temp_test_hwmon_event1", input=0x0, parse_state=0x3ffffff7fb8) at util/parse-events.c:1867 #8 0x000000000126a1e8 in __parse_events (evlist=0x168b580, str=0x3ffffff81d8 "temp_test_hwmon_event1", pmu_filter=0x0, err=0x3ffffff81c8, fake_pmu=false, warn_if_reordered=true, fake_tp=false) at util/parse-events.c:2136 #9 0x00000000011e36aa in parse_events (evlist=0x168b580, str=0x3ffffff81d8 "temp_test_hwmon_event1", err=0x3ffffff81c8) at /root/linux/tools/perf/util/parse-events.h:41 #10 0x00000000011e3e64 in do_test (i=0, with_pmu=false, with_alias=false) at tests/hwmon_pmu.c:164 #11 0x00000000011e422c in test__hwmon_pmu (with_pmu=false) at tests/hwmon_pmu.c:219 #12 0x00000000011e431c in test__hwmon_pmu_without_pmu (test=0x1610368 <suite.hwmon_pmu>, subtest=1) at tests/hwmon_pmu.c:23 where the attr::config is set to value 292470092988416 or 0x10a0000000000 in line 625 of file ./util/hwmon_pmu.c: attr->config = key.type_and_num; However member key::type_and_num is defined as union and bit field: union hwmon_pmu_event_key { long type_and_num; struct { int num :16; enum hwmon_type type :8; }; }; s390 is big endian and Intel is little endian architecture. The events for the hwmon dummy pmu have num = 1 or num = 2 and type is set to HWMON_TYPE_TEMP (which is 10). On s390 this assignes member key::type_and_num the value of 0x10a0000000000 (which is 292470092988416) as shown in above trace output. Fix this and export the structure/union hwmon_pmu_event_key so the test shares the same implementation as the event parsing functions for union and bit fields. This should avoid endianess issues on all platforms. Output after: # ./perf test -F 11 11.1: Basic parsing test : Ok 11.2: Parsing without PMU name : Ok 11.3: Parsing with PMU name : Ok # Fixes: 531ee0f ("perf test: Add hwmon "PMU" test") Signed-off-by: Thomas Richter <tmricht@linux.ibm.com> Reviewed-by: Ian Rogers <irogers@google.com> Link: https://lore.kernel.org/r/20250131112400.568975-1-tmricht@linux.ibm.com Signed-off-by: Namhyung Kim <namhyung@kernel.org>

Ian told me that there are many memory leaks in the hierarchy mode. I can easily reproduce it with the follwing command. $ make DEBUG=1 EXTRA_CFLAGS=-fsanitize=leak $ perf record --latency -g -- ./perf test -w thloop $ perf report -H --stdio ... Indirect leak of 168 byte(s) in 21 object(s) allocated from: #0 0x7f3414c16c65 in malloc ../../../../src/libsanitizer/lsan/lsan_interceptors.cpp:75 #1 0x55ed3602346e in map__get util/map.h:189 #2 0x55ed36024cc4 in hist_entry__init util/hist.c:476 #3 0x55ed36025208 in hist_entry__new util/hist.c:588 #4 0x55ed36027c05 in hierarchy_insert_entry util/hist.c:1587 #5 0x55ed36027e2e in hists__hierarchy_insert_entry util/hist.c:1638 #6 0x55ed36027fa4 in hists__collapse_insert_entry util/hist.c:1685 #7 0x55ed360283e8 in hists__collapse_resort util/hist.c:1776 #8 0x55ed35de0323 in report__collapse_hists /home/namhyung/project/linux/tools/perf/builtin-report.c:735 #9 0x55ed35de15b4 in __cmd_report /home/namhyung/project/linux/tools/perf/builtin-report.c:1119 #10 0x55ed35de43dc in cmd_report /home/namhyung/project/linux/tools/perf/builtin-report.c:1867 #11 0x55ed35e66767 in run_builtin /home/namhyung/project/linux/tools/perf/perf.c:351 #12 0x55ed35e66a0e in handle_internal_command /home/namhyung/project/linux/tools/perf/perf.c:404 #13 0x55ed35e66b67 in run_argv /home/namhyung/project/linux/tools/perf/perf.c:448 #14 0x55ed35e66eb0 in main /home/namhyung/project/linux/tools/perf/perf.c:556 #15 0x7f340ac33d67 in __libc_start_call_main ../sysdeps/nptl/libc_start_call_main.h:58 ... $ perf report -H --stdio 2>&1 | grep -c '^Indirect leak' 93 I found that hist_entry__delete() missed to release child entries in the hierarchy tree (hroot_{in,out}). It needs to iterate the child entries and call hist_entry__delete() recursively. After this change: $ perf report -H --stdio 2>&1 | grep -c '^Indirect leak' 0 Reported-by: Ian Rogers <irogers@google.com> Tested-by Thomas Falcon <thomas.falcon@intel.com> Reviewed-by: Ian Rogers <irogers@google.com> Link: https://lore.kernel.org/r/20250307061250.320849-2-namhyung@kernel.org Signed-off-by: Namhyung Kim <namhyung@kernel.org>

The env.pmu_mapping can be leaked when it reads data from a pipe on AMD. For a pipe data, it reads the header data including pmu_mapping from PERF_RECORD_HEADER_FEATURE runtime. But it's already set in: perf_session__new() __perf_session__new() evlist__init_trace_event_sample_raw() evlist__has_amd_ibs() perf_env__nr_pmu_mappings() Then it'll overwrite that when it processes the HEADER_FEATURE record. Here's a report from address sanitizer. Direct leak of 2689 byte(s) in 1 object(s) allocated from: #0 0x7fed8f814596 in realloc ../../../../src/libsanitizer/lsan/lsan_interceptors.cpp:98 #1 0x5595a7d416b1 in strbuf_grow util/strbuf.c:64 #2 0x5595a7d414ef in strbuf_init util/strbuf.c:25 #3 0x5595a7d0f4b7 in perf_env__read_pmu_mappings util/env.c:362 #4 0x5595a7d12ab7 in perf_env__nr_pmu_mappings util/env.c:517 #5 0x5595a7d89d2f in evlist__has_amd_ibs util/amd-sample-raw.c:315 #6 0x5595a7d87fb2 in evlist__init_trace_event_sample_raw util/sample-raw.c:23 #7 0x5595a7d7f893 in __perf_session__new util/session.c:179 #8 0x5595a7b79572 in perf_session__new util/session.h:115 #9 0x5595a7b7e9dc in cmd_report builtin-report.c:1603 #10 0x5595a7c019eb in run_builtin perf.c:351 #11 0x5595a7c01c92 in handle_internal_command perf.c:404 #12 0x5595a7c01deb in run_argv perf.c:448 #13 0x5595a7c02134 in main perf.c:556 #14 0x7fed85833d67 in __libc_start_call_main ../sysdeps/nptl/libc_start_call_main.h:58 Let's free the existing pmu_mapping data if any. Cc: Ravi Bangoria <ravi.bangoria@amd.com> Link: https://lore.kernel.org/r/20250311000416.817631-1-namhyung@kernel.org Signed-off-by: Namhyung Kim <namhyung@kernel.org>

When a bio with REQ_PREFLUSH is submitted to dm, __send_empty_flush() generates a flush_bio with REQ_OP_WRITE | REQ_PREFLUSH | REQ_SYNC, which causes the flush_bio to be throttled by wbt_wait(). An example from v5.4, similar problem also exists in upstream: crash> bt 2091206 PID: 2091206 TASK: ffff2050df92a300 CPU: 109 COMMAND: "kworker/u260:0" #0 [ffff800084a2f7f0] __switch_to at ffff80004008aeb8 #1 [ffff800084a2f820] __schedule at ffff800040bfa0c4 #2 [ffff800084a2f880] schedule at ffff800040bfa4b4 #3 [ffff800084a2f8a0] io_schedule at ffff800040bfa9c4 #4 [ffff800084a2f8c0] rq_qos_wait at ffff8000405925bc #5 [ffff800084a2f940] wbt_wait at ffff8000405bb3a0 #6 [ffff800084a2f9a0] __rq_qos_throttle at ffff800040592254 #7 [ffff800084a2f9c0] blk_mq_make_request at ffff80004057cf38 #8 [ffff800084a2fa60] generic_make_request at ffff800040570138 #9 [ffff800084a2fae0] submit_bio at ffff8000405703b4 #10 [ffff800084a2fb50] xlog_write_iclog at ffff800001280834 [xfs] #11 [ffff800084a2fbb0] xlog_sync at ffff800001280c3c [xfs] #12 [ffff800084a2fbf0] xlog_state_release_iclog at ffff800001280df4 [xfs] #13 [ffff800084a2fc10] xlog_write at ffff80000128203c [xfs] #14 [ffff800084a2fcd0] xlog_cil_push at ffff8000012846dc [xfs] #15 [ffff800084a2fda0] xlog_cil_push_work at ffff800001284a2c [xfs] #16 [ffff800084a2fdb0] process_one_work at ffff800040111d08 #17 [ffff800084a2fe00] worker_thread at ffff8000401121cc #18 [ffff800084a2fe70] kthread at ffff800040118de4 After commit 2def284 ("xfs: don't allow log IO to be throttled"), the metadata submitted by xlog_write_iclog() should not be throttled. But due to the existence of the dm layer, throttling flush_bio indirectly causes the metadata bio to be throttled. Fix this by conditionally adding REQ_IDLE to flush_bio.bi_opf, which makes wbt_should_throttle() return false to avoid wbt_wait(). Signed-off-by: Jinliang Zheng <alexjlzheng@tencent.com> Reviewed-by: Tianxiang Peng <txpeng@tencent.com> Reviewed-by: Hao Peng <flyingpeng@tencent.com> Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>

v2: - Created a single error handling unlock and exit in veth_pool_store - Greatly expanded commit message with previous explanatory-only text Summary: Use rtnl_mutex to synchronize veth_pool_store with itself, ibmveth_close and ibmveth_open, preventing multiple calls in a row to napi_disable. Background: Two (or more) threads could call veth_pool_store through writing to /sys/devices/vio/30000002/pool*/*. You can do this easily with a little shell script. This causes a hang. I configured LOCKDEP, compiled ibmveth.c with DEBUG, and built a new kernel. I ran this test again and saw: Setting pool0/active to 0 Setting pool1/active to 1 [ 73.911067][ T4365] ibmveth 30000002 eth0: close starting Setting pool1/active to 1 Setting pool1/active to 0 [ 73.911367][ T4366] ibmveth 30000002 eth0: close starting [ 73.916056][ T4365] ibmveth 30000002 eth0: close complete [ 73.916064][ T4365] ibmveth 30000002 eth0: open starting [ 110.808564][ T712] systemd-journald[712]: Sent WATCHDOG=1 notification. [ 230.808495][ T712] systemd-journald[712]: Sent WATCHDOG=1 notification. [ 243.683786][ T123] INFO: task stress.sh:4365 blocked for more than 122 seconds. [ 243.683827][ T123] Not tainted 6.14.0-01103-g2df0c02dab82-dirty #8 [ 243.683833][ T123] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. [ 243.683838][ T123] task:stress.sh state:D stack:28096 pid:4365 tgid:4365 ppid:4364 task_flags:0x400040 flags:0x00042000 [ 243.683852][ T123] Call Trace: [ 243.683857][ T123] [c00000000c38f690] [0000000000000001] 0x1 (unreliable) [ 243.683868][ T123] [c00000000c38f840] [c00000000001f908] __switch_to+0x318/0x4e0 [ 243.683878][ T123] [c00000000c38f8a0] [c000000001549a70] __schedule+0x500/0x12a0 [ 243.683888][ T123] [c00000000c38f9a0] [c00000000154a878] schedule+0x68/0x210 [ 243.683896][ T123] [c00000000c38f9d0] [c00000000154ac80] schedule_preempt_disabled+0x30/0x50 [ 243.683904][ T123] [c00000000c38fa00] [c00000000154dbb0] __mutex_lock+0x730/0x10f0 [ 243.683913][ T123] [c00000000c38fb10] [c000000001154d40] napi_enable+0x30/0x60 [ 243.683921][ T123] [c00000000c38fb40] [c000000000f4ae94] ibmveth_open+0x68/0x5dc [ 243.683928][ T123] [c00000000c38fbe0] [c000000000f4aa20] veth_pool_store+0x220/0x270 [ 243.683936][ T123] [c00000000c38fc70] [c000000000826278] sysfs_kf_write+0x68/0xb0 [ 243.683944][ T123] [c00000000c38fcb0] [c0000000008240b8] kernfs_fop_write_iter+0x198/0x2d0 [ 243.683951][ T123] [c00000000c38fd00] [c00000000071b9ac] vfs_write+0x34c/0x650 [ 243.683958][ T123] [c00000000c38fdc0] [c00000000071bea8] ksys_write+0x88/0x150 [ 243.683966][ T123] [c00000000c38fe10] [c0000000000317f4] system_call_exception+0x124/0x340 [ 243.683973][ T123] [c00000000c38fe50] [c00000000000d05c] system_call_vectored_common+0x15c/0x2ec ... [ 243.684087][ T123] Showing all locks held in the system: [ 243.684095][ T123] 1 lock held by khungtaskd/123: [ 243.684099][ T123] #0: c00000000278e370 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x50/0x248 [ 243.684114][ T123] 4 locks held by stress.sh/4365: [ 243.684119][ T123] #0: c00000003a4cd3f8 (sb_writers#3){.+.+}-{0:0}, at: ksys_write+0x88/0x150 [ 243.684132][ T123] #1: c000000041aea888 (&of->mutex#2){+.+.}-{3:3}, at: kernfs_fop_write_iter+0x154/0x2d0 [ 243.684143][ T123] #2: c0000000366fb9a8 (kn->active#64){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x160/0x2d0 [ 243.684155][ T123] #3: c000000035ff4cb8 (&dev->lock){+.+.}-{3:3}, at: napi_enable+0x30/0x60 [ 243.684166][ T123] 5 locks held by stress.sh/4366: [ 243.684170][ T123] #0: c00000003a4cd3f8 (sb_writers#3){.+.+}-{0:0}, at: ksys_write+0x88/0x150 [ 243.684183][ T123] #1: c00000000aee2288 (&of->mutex#2){+.+.}-{3:3}, at: kernfs_fop_write_iter+0x154/0x2d0 [ 243.684194][ T123] #2: c0000000366f4ba8 (kn->active#64){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x160/0x2d0 [ 243.684205][ T123] #3: c000000035ff4cb8 (&dev->lock){+.+.}-{3:3}, at: napi_disable+0x30/0x60 [ 243.684216][ T123] #4: c0000003ff9bbf18 (&rq->__lock){-.-.}-{2:2}, at: __schedule+0x138/0x12a0 From the ibmveth debug, two threads are calling veth_pool_store, which calls ibmveth_close and ibmveth_open. Here's the sequence: T4365 T4366 ----------------- ----------------- --------- veth_pool_store veth_pool_store ibmveth_close ibmveth_close napi_disable napi_disable ibmveth_open napi_enable <- HANG ibmveth_close calls napi_disable at the top and ibmveth_open calls napi_enable at the top. https://docs.kernel.org/networking/napi.html]] says The control APIs are not idempotent. Control API calls are safe against concurrent use of datapath APIs but an incorrect sequence of control API calls may result in crashes, deadlocks, or race conditions. For example, calling napi_disable() multiple times in a row will deadlock. In the normal open and close paths, rtnl_mutex is acquired to prevent other callers. This is missing from veth_pool_store. Use rtnl_mutex in veth_pool_store fixes these hangs. Signed-off-by: Dave Marquardt <davemarq@linux.ibm.com> Fixes: 860f242 ("[PATCH] ibmveth change buffer pools dynamically") Reviewed-by: Nick Child <nnac123@linux.ibm.com> Reviewed-by: Simon Horman <horms@kernel.org> Link: https://patch.msgid.link/20250402154403.386744-1-davemarq@linux.ibm.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>

ACPICA commit 1c28da2242783579d59767617121035dafba18c3 This was originally done in NetBSD: NetBSD/src@b69d1ac and is the correct alternative to the smattering of `memcpy`s I previously contributed to this repository. This also sidesteps the newly strict checks added in UBSAN: llvm/llvm-project@7926744 Before this change we see the following UBSAN stack trace in Fuchsia: #0 0x000021afcfdeca5e in acpi_rs_get_address_common(struct acpi_resource*, union aml_resource*) ../../third_party/acpica/source/components/resources/rsaddr.c:329 <platform-bus-x86.so>+0x6aca5e #1.2 0x000021982bc4af3c in ubsan_get_stack_trace() compiler-rt/lib/ubsan/ubsan_diag.cpp:41 <libclang_rt.asan.so>+0x41f3c #1.1 0x000021982bc4af3c in maybe_print_stack_trace() compiler-rt/lib/ubsan/ubsan_diag.cpp:51 <libclang_rt.asan.so>+0x41f3c #1 0x000021982bc4af3c in ~scoped_report() compiler-rt/lib/ubsan/ubsan_diag.cpp:395 <libclang_rt.asan.so>+0x41f3c #2 0x000021982bc4bb6f in handletype_mismatch_impl() compiler-rt/lib/ubsan/ubsan_handlers.cpp:137 <libclang_rt.asan.so>+0x42b6f #3 0x000021982bc4b723 in __ubsan_handle_type_mismatch_v1 compiler-rt/lib/ubsan/ubsan_handlers.cpp:142 <libclang_rt.asan.so>+0x42723 #4 0x000021afcfdeca5e in acpi_rs_get_address_common(struct acpi_resource*, union aml_resource*) ../../third_party/acpica/source/components/resources/rsaddr.c:329 <platform-bus-x86.so>+0x6aca5e #5 0x000021afcfdf2089 in acpi_rs_convert_aml_to_resource(struct acpi_resource*, union aml_resource*, struct acpi_rsconvert_info*) ../../third_party/acpica/source/components/resources/rsmisc.c:355 <platform-bus-x86.so>+0x6b2089 #6 0x000021afcfded169 in acpi_rs_convert_aml_to_resources(u8*, u32, u32, u8, void**) ../../third_party/acpica/source/components/resources/rslist.c:137 <platform-bus-x86.so>+0x6ad169 #7 0x000021afcfe2d24a in acpi_ut_walk_aml_resources(struct acpi_walk_state*, u8*, acpi_size, acpi_walk_aml_callback, void**) ../../third_party/acpica/source/components/utilities/utresrc.c:237 <platform-bus-x86.so>+0x6ed24a #8 0x000021afcfde66b7 in acpi_rs_create_resource_list(union acpi_operand_object*, struct acpi_buffer*) ../../third_party/acpica/source/components/resources/rscreate.c:199 <platform-bus-x86.so>+0x6a66b7 #9 0x000021afcfdf6979 in acpi_rs_get_method_data(acpi_handle, const char*, struct acpi_buffer*) ../../third_party/acpica/source/components/resources/rsutils.c:770 <platform-bus-x86.so>+0x6b6979 #10 0x000021afcfdf708f in acpi_walk_resources(acpi_handle, char*, acpi_walk_resource_callback, void*) ../../third_party/acpica/source/components/resources/rsxface.c:731 <platform-bus-x86.so>+0x6b708f #11 0x000021afcfa95dcf in acpi::acpi_impl::walk_resources(acpi::acpi_impl*, acpi_handle, const char*, acpi::Acpi::resources_callable) ../../src/devices/board/lib/acpi/acpi-impl.cc:41 <platform-bus-x86.so>+0x355dcf #12 0x000021afcfaa8278 in acpi::device_builder::gather_resources(acpi::device_builder*, acpi::Acpi*, fidl::any_arena&, acpi::Manager*, acpi::device_builder::gather_resources_callback) ../../src/devices/board/lib/acpi/device-builder.cc:84 <platform-bus-x86.so>+0x368278 #13 0x000021afcfbddb87 in acpi::Manager::configure_discovered_devices(acpi::Manager*) ../../src/devices/board/lib/acpi/manager.cc:75 <platform-bus-x86.so>+0x49db87 #14 0x000021afcf99091d in publish_acpi_devices(acpi::Manager*, zx_device_t*, zx_device_t*) ../../src/devices/board/drivers/x86/acpi-nswalk.cc:95 <platform-bus-x86.so>+0x25091d #15 0x000021afcf9c1d4e in x86::X86::do_init(x86::X86*) ../../src/devices/board/drivers/x86/x86.cc:60 <platform-bus-x86.so>+0x281d4e #16 0x000021afcf9e33ad in λ(x86::X86::ddk_init::(anon class)*) ../../src/devices/board/drivers/x86/x86.cc:77 <platform-bus-x86.so>+0x2a33ad #17 0x000021afcf9e313e in fit::internal::target<(lambda at../../src/devices/board/drivers/x86/x86.cc:76:19), false, false, std::__2::allocator<std::byte>, void>::invoke(void*) ../../sdk/lib/fit/include/lib/fit/internal/function.h:183 <platform-bus-x86.so>+0x2a313e #18 0x000021afcfbab4c7 in fit::internal::function_base<16UL, false, void(), std::__2::allocator<std::byte>>::invoke(const fit::internal::function_base<16UL, false, void (), std::__2::allocator<std::byte> >*) ../../sdk/lib/fit/include/lib/fit/internal/function.h:522 <platform-bus-x86.so>+0x46b4c7 #19 0x000021afcfbab342 in fit::function_impl<16UL, false, void(), std::__2::allocator<std::byte>>::operator()(const fit::function_impl<16UL, false, void (), std::__2::allocator<std::byte> >*) ../../sdk/lib/fit/include/lib/fit/function.h:315 <platform-bus-x86.so>+0x46b342 #20 0x000021afcfcd98c3 in async::internal::retained_task::Handler(async_dispatcher_t*, async_task_t*, zx_status_t) ../../sdk/lib/async/task.cc:24 <platform-bus-x86.so>+0x5998c3 #21 0x00002290f9924616 in λ(const driver_runtime::Dispatcher::post_task::(anon class)*, std::__2::unique_ptr<driver_runtime::callback_request, std::__2::default_delete<driver_runtime::callback_request> >, zx_status_t) ../../src/devices/bin/driver_runtime/dispatcher.cc:789 <libdriver_runtime.so>+0x10a616 #22 0x00002290f9924323 in fit::internal::target<(lambda at../../src/devices/bin/driver_runtime/dispatcher.cc:788:7), true, false, std::__2::allocator<std::byte>, void, std::__2::unique_ptr<driver_runtime::callback_request, std::__2::default_delete<driver_runtime::callback_request>>, int>::invoke(void*, std::__2::unique_ptr<driver_runtime::callback_request, std::__2::default_delete<driver_runtime::callback_request> >, int) ../../sdk/lib/fit/include/lib/fit/internal/function.h:128 <libdriver_runtime.so>+0x10a323 #23 0x00002290f9904b76 in fit::internal::function_base<24UL, true, void(std::__2::unique_ptr<driver_runtime::callback_request, std::__2::default_delete<driver_runtime::callback_request>>, int), std::__2::allocator<std::byte>>::invoke(const fit::internal::function_base<24UL, true, void (std::__2::unique_ptr<driver_runtime::callback_request, std::__2::default_delete<driver_runtime::callback_request> >, int), std::__2::allocator<std::byte> >*, std::__2::unique_ptr<driver_runtime::callback_request, std::__2::default_delete<driver_runtime::callback_request> >, int) ../../sdk/lib/fit/include/lib/fit/internal/function.h:522 <libdriver_runtime.so>+0xeab76 #24 0x00002290f9904831 in fit::callback_impl<24UL, true, void(std::__2::unique_ptr<driver_runtime::callback_request, std::__2::default_delete<driver_runtime::callback_request>>, int), std::__2::allocator<std::byte>>::operator()(fit::callback_impl<24UL, true, void (std::__2::unique_ptr<driver_runtime::callback_request, std::__2::default_delete<driver_runtime::callback_request> >, int), std::__2::allocator<std::byte> >*, std::__2::unique_ptr<driver_runtime::callback_request, std::__2::default_delete<driver_runtime::callback_request> >, int) ../../sdk/lib/fit/include/lib/fit/function.h:471 <libdriver_runtime.so>+0xea831 #25 0x00002290f98d5adc in driver_runtime::callback_request::Call(driver_runtime::callback_request*, std::__2::unique_ptr<driver_runtime::callback_request, std::__2::default_delete<driver_runtime::callback_request> >, zx_status_t) ../../src/devices/bin/driver_runtime/callback_request.h:74 <libdriver_runtime.so>+0xbbadc #26 0x00002290f98e1e58 in driver_runtime::Dispatcher::dispatch_callback(driver_runtime::Dispatcher*, std::__2::unique_ptr<driver_runtime::callback_request, std::__2::default_delete<driver_runtime::callback_request> >) ../../src/devices/bin/driver_runtime/dispatcher.cc:1248 <libdriver_runtime.so>+0xc7e58 #27 0x00002290f98e4159 in driver_runtime::Dispatcher::dispatch_callbacks(driver_runtime::Dispatcher*, std::__2::unique_ptr<driver_runtime::Dispatcher::event_waiter, std::__2::default_delete<driver_runtime::Dispatcher::event_waiter> >, fbl::ref_ptr<driver_runtime::Dispatcher>) ../../src/devices/bin/driver_runtime/dispatcher.cc:1308 <libdriver_runtime.so>+0xca159 #28 0x00002290f9918414 in λ(const driver_runtime::Dispatcher::create_with_adder::(anon class)*, std::__2::unique_ptr<driver_runtime::Dispatcher::event_waiter, std::__2::default_delete<driver_runtime::Dispatcher::event_waiter> >, fbl::ref_ptr<driver_runtime::Dispatcher>) ../../src/devices/bin/driver_runtime/dispatcher.cc:353 <libdriver_runtime.so>+0xfe414 #29 0x00002290f991812d in fit::internal::target<(lambda at../../src/devices/bin/driver_runtime/dispatcher.cc:351:7), true, false, std::__2::allocator<std::byte>, void, std::__2::unique_ptr<driver_runtime::Dispatcher::event_waiter, std::__2::default_delete<driver_runtime::Dispatcher::event_waiter>>, fbl::ref_ptr<driver_runtime::Dispatcher>>::invoke(void*, std::__2::unique_ptr<driver_runtime::Dispatcher::event_waiter, std::__2::default_delete<driver_runtime::Dispatcher::event_waiter> >, fbl::ref_ptr<driver_runtime::Dispatcher>) ../../sdk/lib/fit/include/lib/fit/internal/function.h:128 <libdriver_runtime.so>+0xfe12d #30 0x00002290f9906fc7 in fit::internal::function_base<8UL, true, void(std::__2::unique_ptr<driver_runtime::Dispatcher::event_waiter, std::__2::default_delete<driver_runtime::Dispatcher::event_waiter>>, fbl::ref_ptr<driver_runtime::Dispatcher>), std::__2::allocator<std::byte>>::invoke(const fit::internal::function_base<8UL, true, void (std::__2::unique_ptr<driver_runtime::Dispatcher::event_waiter, std::__2::default_delete<driver_runtime::Dispatcher::event_waiter> >, fbl::ref_ptr<driver_runtime::Dispatcher>), std::__2::allocator<std::byte> >*, std::__2::unique_ptr<driver_runtime::Dispatcher::event_waiter, std::__2::default_delete<driver_runtime::Dispatcher::event_waiter> >, fbl::ref_ptr<driver_runtime::Dispatcher>) ../../sdk/lib/fit/include/lib/fit/internal/function.h:522 <libdriver_runtime.so>+0xecfc7 #31 0x00002290f9906c66 in fit::function_impl<8UL, true, void(std::__2::unique_ptr<driver_runtime::Dispatcher::event_waiter, std::__2::default_delete<driver_runtime::Dispatcher::event_waiter>>, fbl::ref_ptr<driver_runtime::Dispatcher>), std::__2::allocator<std::byte>>::operator()(const fit::function_impl<8UL, true, void (std::__2::unique_ptr<driver_runtime::Dispatcher::event_waiter, std::__2::default_delete<driver_runtime::Dispatcher::event_waiter> >, fbl::ref_ptr<driver_runtime::Dispatcher>), std::__2::allocator<std::byte> >*, std::__2::unique_ptr<driver_runtime::Dispatcher::event_waiter, std::__2::default_delete<driver_runtime::Dispatcher::event_waiter> >, fbl::ref_ptr<driver_runtime::Dispatcher>) ../../sdk/lib/fit/include/lib/fit/function.h:315 <libdriver_runtime.so>+0xecc66 #32 0x00002290f98e73d9 in driver_runtime::Dispatcher::event_waiter::invoke_callback(driver_runtime::Dispatcher::event_waiter*, std::__2::unique_ptr<driver_runtime::Dispatcher::event_waiter, std::__2::default_delete<driver_runtime::Dispatcher::event_waiter> >, fbl::ref_ptr<driver_runtime::Dispatcher>) ../../src/devices/bin/driver_runtime/dispatcher.h:543 <libdriver_runtime.so>+0xcd3d9 #33 0x00002290f98e700d in driver_runtime::Dispatcher::event_waiter::handle_event(std::__2::unique_ptr<driver_runtime::Dispatcher::event_waiter, std::__2::default_delete<driver_runtime::Dispatcher::event_waiter> >, async_dispatcher_t*, async::wait_base*, zx_status_t, zx_packet_signal_t const*) ../../src/devices/bin/driver_runtime/dispatcher.cc:1442 <libdriver_runtime.so>+0xcd00d #34 0x00002290f9918983 in async_loop_owned_event_handler<driver_runtime::Dispatcher::event_waiter>::handle_event(async_loop_owned_event_handler<driver_runtime::Dispatcher::event_waiter>*, async_dispatcher_t*, async::wait_base*, zx_status_t, zx_packet_signal_t const*) ../../src/devices/bin/driver_runtime/async_loop_owned_event_handler.h:59 <libdriver_runtime.so>+0xfe983 #35 0x00002290f9918b9e in async::wait_method<async_loop_owned_event_handler<driver_runtime::Dispatcher::event_waiter>, &async_loop_owned_event_handler<driver_runtime::Dispatcher::event_waiter>::handle_event>::call_handler(async_dispatcher_t*, async_wait_t*, zx_status_t, zx_packet_signal_t const*) ../../sdk/lib/async/include/lib/async/cpp/wait.h:201 <libdriver_runtime.so>+0xfeb9e #36 0x00002290f99bf509 in async_loop_dispatch_wait(async_loop_t*, async_wait_t*, zx_status_t, zx_packet_signal_t const*) ../../sdk/lib/async-loop/loop.c:394 <libdriver_runtime.so>+0x1a5509 #37 0x00002290f99b9958 in async_loop_run_once(async_loop_t*, zx_time_t) ../../sdk/lib/async-loop/loop.c:343 <libdriver_runtime.so>+0x19f958 #38 0x00002290f99b9247 in async_loop_run(async_loop_t*, zx_time_t, _Bool) ../../sdk/lib/async-loop/loop.c:301 <libdriver_runtime.so>+0x19f247 #39 0x00002290f99ba962 in async_loop_run_thread(void*) ../../sdk/lib/async-loop/loop.c:860 <libdriver_runtime.so>+0x1a0962 #40 0x000041afd176ef30 in start_c11(void*) ../../zircon/third_party/ulib/musl/pthread/pthread_create.c:63 <libc.so>+0x84f30 #41 0x000041afd18a448d in thread_trampoline(uintptr_t, uintptr_t) ../../zircon/system/ulib/runtime/thread.cc:100 <libc.so>+0x1ba48d Link: acpica/acpica@1c28da22 Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Link: https://patch.msgid.link/4664267.LvFx2qVVIh@rjwysocki.net Signed-off-by: Tamir Duberstein <tamird@gmail.com> [ rjw: Pick up the tag from Tamir ] Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

Biju Das <biju.das.jz@bp.renesas.com> says: The CAN-FD module on RZ/G3E is very similar to the one on both R-Car V4H and RZ/G2L, but differs in some hardware parameters: * No external clock, but instead has ram clock. * Support up to 6 channels. * 20 interrupts. v8->v9: * Collected tags. * Added missing header bitfield.h. * Fixed logical error ch->BIT(ch) in rcar_canfd_global_error(). * Removed unneeded double space in rcar_canfd_setrnc(). * Updated commit description in patch#15. v7->v8: * Collected tags. * Updated commit description for patch#{5,9,15,16,17}. * Replaced the macro RCANFD_GERFL_EEF0_7->RCANFD_GERFL_EEF. * Dropped the redundant macro RCANFD_GERFL_EEF(ch). * Added patch for dropping the mask operation in RCANFD_GAFLCFG_SETRNC macro. * Converted RCANFD_GAFLCFG_SETRNC->rcar_canfd_setrnc(). * Updated RCANFD_GAFLCFG macro by replacing the parameter ch->w, where w is the GAFLCFG index used in the hardware manual. * Renamed the parameter x->page_num in RCANFD_GAFLECTR_AFLPN macro to make it clear. * Renamed the parameter x->cftml in RCANFD_CFCC_CFTML macro to make it clear. * Updated {rzg2l,car_gen3_hw_info} with ch_interface_mode = 0. * Updated {rzg2l,rcar_gen3}_hw_info with shared_can_regs = 0. * Started using struct rcanfd_regs instead of LUT for reg offsets. * Started using struct rcar_canfd_shift_data instead of LUT for shift data. * Renamed only_internal_clks->external_clk to avoid negation. * Updated rcar_canfd_hw_info tables with external_clk entries. * Replaced 10->sizeof(name) in scnprintf(). v6->v7: * Collected tags * Replaced 'aswell'->'as well' in patch#11 commit description. v5->v6: * Replaced RCANFD_RNC_PER_REG macro with rnc_stride variable. * Updated commit description for patch#7 and #8 * Dropped mask_table: AFLPN_MASK is replaced by max_aflpn variable. CFTML_MASK is replaced by max_cftml variable. BITTIMING MASK's are replaced by {nom,data}_bittiming variables. * Collected tag from Geert. v4->v5: * Collected tag from Geert. * The rules for R-Car Gen3/4 could be kept together, reducing the number of lines. Similar change for rzg2l-canfd aswell. * Keeping interrupts and resets together allows to keep a clear separation between RZ/G2L and RZ/G3E, at the expense of only a single line. * Retained the tags for binding patches as it is trivial changes. * Dropped the unused macro RCANFD_GAFLCFG_GETRNC. * Updated macro RCANFD_GERFL_ERR by using gpriv->channels_mask and dropped unused macro RCANFD_GERFL_EEF0_7. * Replaced RNC mask in RCANFD_GAFLCFG_SETRNC macro by using info->num_supported_rules variable. * Updated the macro RCANFD_GAFLCFG by using info->rnc_field_width variable. * Updated shift value in RCANFD_GAFLCFG_SETRNC macro by using a formula (32 - (n % rnc_per_reg + 1) * field_width). * Replaced the variable name shared_can_reg->shared_can_regs. * Improved commit description for patch{#11,#12}by replacing has->have. * Dropped RCANFD_EEF_MASK and RCANFD_RNC_MASK as it is taken care by gpriv->channels_mask and info->num_supported_rules. * Dropped RCANFD_FIRST_RNC_SH and RCANFD_SECOND_RNC_SH by using a formula (32 - (n % rnc_per_reg + 1) * rnc_field_width. * Improved commit description by "All SoCs supports extenal clock"-> "All existing SoCs support an external clock". * Updated error description in probe as "cannot get enabled ram clock" * Updated r9a09g047_hw_info table. v3->v4: * Added Rb tag from Rob for patch#2. * Added prefix RCANFD_* to enum rcar_canfd_reg_offset_id. * Added prefix RCANFD_* to enum rcar_canfd_mask_id. * Added prefix RCANFD_* to enum rcar_canfd_shift_id. v2->v3: * Collected tags. * Dropped reg_gen4() and is_gen4() by adding mask_table, shift_table, regs, ch_interface_mode and shared_can_reg variables to struct rcar_canfd_hw_info. v1->v2: * Split the series with fixes patch separately. * Added patch for Simplify rcar_canfd_probe() using of_get_available_child_by_name() as dependency patch hit on can-next. * Added Rb tag from Vincent Mailhol. * Dropped redundant comment from commit description for patch#3. Link: https://patch.msgid.link/20250417054320.14100-1-biju.das.jz@bp.renesas.com Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>

Jann Horn reported a use-after-free in unix_stream_read_generic(). The following sequences reproduce the issue: $ python3 from socket import * s1, s2 = socketpair(AF_UNIX, SOCK_STREAM) s1.send(b'x', MSG_OOB) s2.recv(1, MSG_OOB) # leave a consumed OOB skb s1.send(b'y', MSG_OOB) s2.recv(1, MSG_OOB) # leave a consumed OOB skb s1.send(b'z', MSG_OOB) s2.recv(1) # recv 'z' illegally s2.recv(1, MSG_OOB) # access 'z' skb (use-after-free) Even though a user reads OOB data, the skb holding the data stays on the recv queue to mark the OOB boundary and break the next recv(). After the last send() in the scenario above, the sk2's recv queue has 2 leading consumed OOB skbs and 1 real OOB skb. Then, the following happens during the next recv() without MSG_OOB 1. unix_stream_read_generic() peeks the first consumed OOB skb 2. manage_oob() returns the next consumed OOB skb 3. unix_stream_read_generic() fetches the next not-yet-consumed OOB skb 4. unix_stream_read_generic() reads and frees the OOB skb , and the last recv(MSG_OOB) triggers KASAN splat. The 3. above occurs because of the SO_PEEK_OFF code, which does not expect unix_skb_len(skb) to be 0, but this is true for such consumed OOB skbs. while (skip >= unix_skb_len(skb)) { skip -= unix_skb_len(skb); skb = skb_peek_next(skb, &sk->sk_receive_queue); ... } In addition to this use-after-free, there is another issue that ioctl(SIOCATMARK) does not function properly with consecutive consumed OOB skbs. So, nothing good comes out of such a situation. Instead of complicating manage_oob(), ioctl() handling, and the next ECONNRESET fix by introducing a loop for consecutive consumed OOB skbs, let's not leave such consecutive OOB unnecessarily. Now, while receiving an OOB skb in unix_stream_recv_urg(), if its previous skb is a consumed OOB skb, it is freed. [0]: BUG: KASAN: slab-use-after-free in unix_stream_read_actor (net/unix/af_unix.c:3027) Read of size 4 at addr ffff888106ef2904 by task python3/315 CPU: 2 UID: 0 PID: 315 Comm: python3 Not tainted 6.16.0-rc1-00407-gec315832f6f9 #8 PREEMPT(voluntary) Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.16.3-4.fc42 04/01/2014 Call Trace: <TASK> dump_stack_lvl (lib/dump_stack.c:122) print_report (mm/kasan/report.c:409 mm/kasan/report.c:521) kasan_report (mm/kasan/report.c:636) unix_stream_read_actor (net/unix/af_unix.c:3027) unix_stream_read_generic (net/unix/af_unix.c:2708 net/unix/af_unix.c:2847) unix_stream_recvmsg (net/unix/af_unix.c:3048) sock_recvmsg (net/socket.c:1063 (discriminator 20) net/socket.c:1085 (discriminator 20)) __sys_recvfrom (net/socket.c:2278) __x64_sys_recvfrom (net/socket.c:2291 (discriminator 1) net/socket.c:2287 (discriminator 1) net/socket.c:2287 (discriminator 1)) do_syscall_64 (arch/x86/entry/syscall_64.c:63 (discriminator 1) arch/x86/entry/syscall_64.c:94 (discriminator 1)) entry_SYSCALL_64_after_hwframe (arch/x86/entry/entry_64.S:130) RIP: 0033:0x7f8911fcea06 Code: 5d e8 41 8b 93 08 03 00 00 59 5e 48 83 f8 fc 75 19 83 e2 39 83 fa 08 75 11 e8 26 ff ff ff 66 0f 1f 44 00 00 48 8b 45 10 0f 05 <48> 8b 5d f8 c9 c3 0f 1f 40 00 f3 0f 1e fa 55 48 89 e5 48 83 ec 08 RSP: 002b:00007fffdb0dccb0 EFLAGS: 00000202 ORIG_RAX: 000000000000002d RAX: ffffffffffffffda RBX: 00007fffdb0dcdc8 RCX: 00007f8911fcea06 RDX: 0000000000000001 RSI: 00007f8911a5e060 RDI: 0000000000000006 RBP: 00007fffdb0dccd0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000001 R11: 0000000000000202 R12: 00007f89119a7d20 R13: ffffffffc4653600 R14: 0000000000000000 R15: 0000000000000000 </TASK> Allocated by task 315: kasan_save_stack (mm/kasan/common.c:48) kasan_save_track (mm/kasan/common.c:60 (discriminator 1) mm/kasan/common.c:69 (discriminator 1)) __kasan_slab_alloc (mm/kasan/common.c:348) kmem_cache_alloc_node_noprof (./include/linux/kasan.h:250 mm/slub.c:4148 mm/slub.c:4197 mm/slub.c:4249) __alloc_skb (net/core/skbuff.c:660 (discriminator 4)) alloc_skb_with_frags (./include/linux/skbuff.h:1336 net/core/skbuff.c:6668) sock_alloc_send_pskb (net/core/sock.c:2993) unix_stream_sendmsg (./include/net/sock.h:1847 net/unix/af_unix.c:2256 net/unix/af_unix.c:2418) __sys_sendto (net/socket.c:712 (discriminator 20) net/socket.c:727 (discriminator 20) net/socket.c:2226 (discriminator 20)) __x64_sys_sendto (net/socket.c:2233 (discriminator 1) net/socket.c:2229 (discriminator 1) net/socket.c:2229 (discriminator 1)) do_syscall_64 (arch/x86/entry/syscall_64.c:63 (discriminator 1) arch/x86/entry/syscall_64.c:94 (discriminator 1)) entry_SYSCALL_64_after_hwframe (arch/x86/entry/entry_64.S:130) Freed by task 315: kasan_save_stack (mm/kasan/common.c:48) kasan_save_track (mm/kasan/common.c:60 (discriminator 1) mm/kasan/common.c:69 (discriminator 1)) kasan_save_free_info (mm/kasan/generic.c:579 (discriminator 1)) __kasan_slab_free (mm/kasan/common.c:271) kmem_cache_free (mm/slub.c:4643 (discriminator 3) mm/slub.c:4745 (discriminator 3)) unix_stream_read_generic (net/unix/af_unix.c:3010) unix_stream_recvmsg (net/unix/af_unix.c:3048) sock_recvmsg (net/socket.c:1063 (discriminator 20) net/socket.c:1085 (discriminator 20)) __sys_recvfrom (net/socket.c:2278) __x64_sys_recvfrom (net/socket.c:2291 (discriminator 1) net/socket.c:2287 (discriminator 1) net/socket.c:2287 (discriminator 1)) do_syscall_64 (arch/x86/entry/syscall_64.c:63 (discriminator 1) arch/x86/entry/syscall_64.c:94 (discriminator 1)) entry_SYSCALL_64_after_hwframe (arch/x86/entry/entry_64.S:130) The buggy address belongs to the object at ffff888106ef28c0 which belongs to the cache skbuff_head_cache of size 224 The buggy address is located 68 bytes inside of freed 224-byte region [ffff888106ef28c0, ffff888106ef29a0) The buggy address belongs to the physical page: page: refcount:0 mapcount:0 mapping:0000000000000000 index:0xffff888106ef3cc0 pfn:0x106ef2 head: order:1 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0 flags: 0x200000000000040(head|node=0|zone=2) page_type: f5(slab) raw: 0200000000000040 ffff8881001d28c0 ffffea000422fe00 0000000000000004 raw: ffff888106ef3cc0 0000000080190010 00000000f5000000 0000000000000000 head: 0200000000000040 ffff8881001d28c0 ffffea000422fe00 0000000000000004 head: ffff888106ef3cc0 0000000080190010 00000000f5000000 0000000000000000 head: 0200000000000001 ffffea00041bbc81 00000000ffffffff 00000000ffffffff head: 0000000000000000 0000000000000000 00000000ffffffff 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff888106ef2800: 00 00 00 00 00 00 00 00 00 00 00 00 fc fc fc fc ffff888106ef2880: fc fc fc fc fc fc fc fc fa fb fb fb fb fb fb fb >ffff888106ef2900: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff888106ef2980: fb fb fb fb fc fc fc fc fc fc fc fc fc fc fc fc ffff888106ef2a00: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb Fixes: 314001f ("af_unix: Add OOB support") Reported-by: Jann Horn <jannh@google.com> Signed-off-by: Kuniyuki Iwashima <kuniyu@google.com> Reviewed-by: Jann Horn <jannh@google.com> Link: https://patch.msgid.link/20250619041457.1132791-2-kuni1840@gmail.com Signed-off-by: Paolo Abeni <pabeni@redhat.com>

A crash in conntrack was reported while trying to unlink the conntrack entry from the hash bucket list: [exception RIP: __nf_ct_delete_from_lists+172] [..] #7 [ff539b5a2b043aa0] nf_ct_delete at ffffffffc124d421 [nf_conntrack] #8 [ff539b5a2b043ad0] nf_ct_gc_expired at ffffffffc124d999 [nf_conntrack] #9 [ff539b5a2b043ae0] __nf_conntrack_find_get at ffffffffc124efbc [nf_conntrack] [..] The nf_conn struct is marked as allocated from slab but appears to be in a partially initialised state: ct hlist pointer is garbage; looks like the ct hash value (hence crash). ct->status is equal to IPS_CONFIRMED|IPS_DYING, which is expected ct->timeout is 30000 (=30s), which is unexpected. Everything else looks like normal udp conntrack entry. If we ignore ct->status and pretend its 0, the entry matches those that are newly allocated but not yet inserted into the hash: - ct hlist pointers are overloaded and store/cache the raw tuple hash - ct->timeout matches the relative time expected for a new udp flow rather than the absolute 'jiffies' value. If it were not for the presence of IPS_CONFIRMED, __nf_conntrack_find_get() would have skipped the entry. Theory is that we did hit following race: cpu x cpu y cpu z found entry E found entry E E is expired <preemption> nf_ct_delete() return E to rcu slab init_conntrack E is re-inited, ct->status set to 0 reply tuplehash hnnode.pprev stores hash value. cpu y found E right before it was deleted on cpu x. E is now re-inited on cpu z. cpu y was preempted before checking for expiry and/or confirm bit. ->refcnt set to 1 E now owned by skb ->timeout set to 30000 If cpu y were to resume now, it would observe E as expired but would skip E due to missing CONFIRMED bit. nf_conntrack_confirm gets called sets: ct->status |= CONFIRMED This is wrong: E is not yet added to hashtable. cpu y resumes, it observes E as expired but CONFIRMED: <resumes> nf_ct_expired() -> yes (ct->timeout is 30s) confirmed bit set. cpu y will try to delete E from the hashtable: nf_ct_delete() -> set DYING bit __nf_ct_delete_from_lists Even this scenario doesn't guarantee a crash: cpu z still holds the table bucket lock(s) so y blocks: wait for spinlock held by z CONFIRMED is set but there is no guarantee ct will be added to hash: "chaintoolong" or "clash resolution" logic both skip the insert step. reply hnnode.pprev still stores the hash value. unlocks spinlock return NF_DROP <unblocks, then crashes on hlist_nulls_del_rcu pprev> In case CPU z does insert the entry into the hashtable, cpu y will unlink E again right away but no crash occurs. Without 'cpu y' race, 'garbage' hlist is of no consequence: ct refcnt remains at 1, eventually skb will be free'd and E gets destroyed via: nf_conntrack_put -> nf_conntrack_destroy -> nf_ct_destroy. To resolve this, move the IPS_CONFIRMED assignment after the table insertion but before the unlock. Pablo points out that the confirm-bit-store could be reordered to happen before hlist add resp. the timeout fixup, so switch to set_bit and before_atomic memory barrier to prevent this. It doesn't matter if other CPUs can observe a newly inserted entry right before the CONFIRMED bit was set: Such event cannot be distinguished from above "E is the old incarnation" case: the entry will be skipped. Also change nf_ct_should_gc() to first check the confirmed bit. The gc sequence is: 1. Check if entry has expired, if not skip to next entry 2. Obtain a reference to the expired entry. 3. Call nf_ct_should_gc() to double-check step 1. nf_ct_should_gc() is thus called only for entries that already failed an expiry check. After this patch, once the confirmed bit check passes ct->timeout has been altered to reflect the absolute 'best before' date instead of a relative time. Step 3 will therefore not remove the entry. Without this change to nf_ct_should_gc() we could still get this sequence: 1. Check if entry has expired. 2. Obtain a reference. 3. Call nf_ct_should_gc() to double-check step 1: 4 - entry is still observed as expired 5 - meanwhile, ct->timeout is corrected to absolute value on other CPU and confirm bit gets set 6 - confirm bit is seen 7 - valid entry is removed again First do check 6), then 4) so the gc expiry check always picks up either confirmed bit unset (entry gets skipped) or expiry re-check failure for re-inited conntrack objects. This change cannot be backported to releases before 5.19. Without commit 8a75a2c ("netfilter: conntrack: remove unconfirmed list") |= IPS_CONFIRMED line cannot be moved without further changes. Cc: Razvan Cojocaru <rzvncj@gmail.com> Link: https://lore.kernel.org/netfilter-devel/20250627142758.25664-1-fw@strlen.de/ Link: https://lore.kernel.org/netfilter-devel/4239da15-83ff-4ca4-939d-faef283471bb@gmail.com/ Fixes: 1397af5 ("netfilter: conntrack: remove the percpu dying list") Signed-off-by: Florian Westphal <fw@strlen.de> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>

It is reported that on Acer Nitro V15 suspend only works properly if the keyboard backlight is turned off. In looking through the issue Acer Nitro V15 has a GPIO (#8) specified in _AEI but it has no matching notify device in _EVT. The values for GPIO #8 change as keyboard backlight is turned on and off. This makes it seem that GPIO #8 is actually supposed to be solely for keyboard backlight. Turning off the interrupt for this GPIO fixes the issue. Add a quirk that does just that. Closes: https://gitlab.freedesktop.org/drm/amd/-/issues/4169 Signed-off-by: Mario Limonciello <mario.limonciello@amd.com> Acked-by: Mika Westerberg <westeri@kernel.org> Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>

pert script tests fails with segmentation fault as below: 92: perf script tests: --- start --- test child forked, pid 103769 DB test [ perf record: Woken up 1 times to write data ] [ perf record: Captured and wrote 0.012 MB /tmp/perf-test-script.7rbftEpOzX/perf.data (9 samples) ] /usr/libexec/perf-core/tests/shell/script.sh: line 35: 103780 Segmentation fault (core dumped) perf script -i "${perfdatafile}" -s "${db_test}" --- Cleaning up --- ---- end(-1) ---- 92: perf script tests : FAILED! Backtrace pointed to : #0 0x0000000010247dd0 in maps.machine () #1 0x00000000101d178c in db_export.sample () #2 0x00000000103412c8 in python_process_event () #3 0x000000001004eb28 in process_sample_event () #4 0x000000001024fcd0 in machines.deliver_event () #5 0x000000001025005c in perf_session.deliver_event () #6 0x00000000102568b0 in __ordered_events__flush.part.0 () #7 0x0000000010251618 in perf_session.process_events () #8 0x0000000010053620 in cmd_script () #9 0x00000000100b5a28 in run_builtin () #10 0x00000000100b5f94 in handle_internal_command () #11 0x0000000010011114 in main () Further investigation reveals that this occurs in the `perf script tests`, because it uses `db_test.py` script. This script sets `perf_db_export_mode = True`. With `perf_db_export_mode` enabled, if a sample originates from a hypervisor, perf doesn't set maps for "[H]" sample in the code. Consequently, `al->maps` remains NULL when `maps__machine(al->maps)` is called from `db_export__sample`. As al->maps can be NULL in case of Hypervisor samples , use thread->maps because even for Hypervisor sample, machine should exist. If we don't have machine for some reason, return -1 to avoid segmentation fault. Reported-by: Disha Goel <disgoel@linux.ibm.com> Signed-off-by: Aditya Bodkhe <aditya.b1@linux.ibm.com> Reviewed-by: Adrian Hunter <adrian.hunter@intel.com> Tested-by: Disha Goel <disgoel@linux.ibm.com> Link: https://lore.kernel.org/r/20250429065132.36839-1-adityab1@linux.ibm.com Suggested-by: Adrian Hunter <adrian.hunter@intel.com> Signed-off-by: Namhyung Kim <namhyung@kernel.org>

Without the change `perf `hangs up on charaster devices. On my system it's enough to run system-wide sampler for a few seconds to get the hangup: $ perf record -a -g --call-graph=dwarf $ perf report # hung `strace` shows that hangup happens on reading on a character device `/dev/dri/renderD128` $ strace -y -f -p 2780484 strace: Process 2780484 attached pread64(101</dev/dri/renderD128>, strace: Process 2780484 detached It's call trace descends into `elfutils`: $ gdb -p 2780484 (gdb) bt #0 0x00007f5e508f04b7 in __libc_pread64 (fd=101, buf=0x7fff9df7edb0, count=0, offset=0) at ../sysdeps/unix/sysv/linux/pread64.c:25 #1 0x00007f5e52b79515 in read_file () from /<<NIX>>/elfutils-0.192/lib/libelf.so.1 #2 0x00007f5e52b25666 in libdw_open_elf () from /<<NIX>>/elfutils-0.192/lib/libdw.so.1 #3 0x00007f5e52b25907 in __libdw_open_file () from /<<NIX>>/elfutils-0.192/lib/libdw.so.1 #4 0x00007f5e52b120a9 in dwfl_report_elf@@ELFUTILS_0.156 () from /<<NIX>>/elfutils-0.192/lib/libdw.so.1 #5 0x000000000068bf20 in __report_module (al=al@entry=0x7fff9df80010, ip=ip@entry=139803237033216, ui=ui@entry=0x5369b5e0) at util/dso.h:537 #6 0x000000000068c3d1 in report_module (ip=139803237033216, ui=0x5369b5e0) at util/unwind-libdw.c:114 #7 frame_callback (state=0x535aef10, arg=0x5369b5e0) at util/unwind-libdw.c:242 #8 0x00007f5e52b261d3 in dwfl_thread_getframes () from /<<NIX>>/elfutils-0.192/lib/libdw.so.1 #9 0x00007f5e52b25bdb in get_one_thread_cb () from /<<NIX>>/elfutils-0.192/lib/libdw.so.1 #10 0x00007f5e52b25faa in dwfl_getthreads () from /<<NIX>>/elfutils-0.192/lib/libdw.so.1 #11 0x00007f5e52b26514 in dwfl_getthread_frames () from /<<NIX>>/elfutils-0.192/lib/libdw.so.1 #12 0x000000000068c6ce in unwind__get_entries (cb=cb@entry=0x5d4620 <unwind_entry>, arg=arg@entry=0x10cd5fa0, thread=thread@entry=0x1076a290, data=data@entry=0x7fff9df80540, max_stack=max_stack@entry=127, best_effort=best_effort@entry=false) at util/thread.h:152 #13 0x00000000005dae95 in thread__resolve_callchain_unwind (evsel=0x106006d0, thread=0x1076a290, cursor=0x10cd5fa0, sample=0x7fff9df80540, max_stack=127, symbols=true) at util/machine.c:2939 #14 thread__resolve_callchain_unwind (thread=0x1076a290, cursor=0x10cd5fa0, evsel=0x106006d0, sample=0x7fff9df80540, max_stack=127, symbols=true) at util/machine.c:2920 #15 __thread__resolve_callchain (thread=0x1076a290, cursor=0x10cd5fa0, evsel=0x106006d0, evsel@entry=0x7fff9df80440, sample=0x7fff9df80540, parent=parent@entry=0x7fff9df804a0, root_al=root_al@entry=0x7fff9df80440, max_stack=127, symbols=true) at util/machine.c:2970 #16 0x00000000005d0cb2 in thread__resolve_callchain (thread=<optimized out>, cursor=<optimized out>, evsel=0x7fff9df80440, sample=<optimized out>, parent=0x7fff9df804a0, root_al=0x7fff9df80440, max_stack=127) at util/machine.h:198 #17 sample__resolve_callchain (sample=<optimized out>, cursor=<optimized out>, parent=parent@entry=0x7fff9df804a0, evsel=evsel@entry=0x106006d0, al=al@entry=0x7fff9df80440, max_stack=max_stack@entry=127) at util/callchain.c:1127 #18 0x0000000000617e08 in hist_entry_iter__add (iter=iter@entry=0x7fff9df80480, al=al@entry=0x7fff9df80440, max_stack_depth=127, arg=arg@entry=0x7fff9df81ae0) at util/hist.c:1255 #19 0x000000000045d2d0 in process_sample_event (tool=0x7fff9df81ae0, event=<optimized out>, sample=0x7fff9df80540, evsel=0x106006d0, machine=<optimized out>) at builtin-report.c:334 #20 0x00000000005e3bb1 in perf_session__deliver_event (session=0x105ff2c0, event=0x7f5c7d735ca0, tool=0x7fff9df81ae0, file_offset=2914716832, file_path=0x105ffbf0 "perf.data") at util/session.c:1367 #21 0x00000000005e8d93 in do_flush (oe=0x105ffa50, show_progress=false) at util/ordered-events.c:245 #22 __ordered_events__flush (oe=0x105ffa50, how=OE_FLUSH__ROUND, timestamp=<optimized out>) at util/ordered-events.c:324 #23 0x00000000005e1f64 in perf_session__process_user_event (session=0x105ff2c0, event=0x7f5c7d752b18, file_offset=2914835224, file_path=0x105ffbf0 "perf.data") at util/session.c:1419 #24 0x00000000005e47c7 in reader__read_event (rd=rd@entry=0x7fff9df81260, session=session@entry=0x105ff2c0, --Type <RET> for more, q to quit, c to continue without paging-- quit prog=prog@entry=0x7fff9df81220) at util/session.c:2132 #25 0x00000000005e4b37 in reader__process_events (rd=0x7fff9df81260, session=0x105ff2c0, prog=0x7fff9df81220) at util/session.c:2181 #26 __perf_session__process_events (session=0x105ff2c0) at util/session.c:2226 #27 perf_session__process_events (session=session@entry=0x105ff2c0) at util/session.c:2390 #28 0x0000000000460add in __cmd_report (rep=0x7fff9df81ae0) at builtin-report.c:1076 #29 cmd_report (argc=<optimized out>, argv=<optimized out>) at builtin-report.c:1827 #30 0x00000000004c5a40 in run_builtin (p=p@entry=0xd8f7f8 <commands+312>, argc=argc@entry=1, argv=argv@entry=0x7fff9df844b0) at perf.c:351 #31 0x00000000004c5d63 in handle_internal_command (argc=argc@entry=1, argv=argv@entry=0x7fff9df844b0) at perf.c:404 #32 0x0000000000442de3 in run_argv (argcp=<synthetic pointer>, argv=<synthetic pointer>) at perf.c:448 #33 main (argc=<optimized out>, argv=0x7fff9df844b0) at perf.c:556 The hangup happens because nothing in` perf` or `elfutils` checks if a mapped file is easily readable. The change conservatively skips all non-regular files. Signed-off-by: Sergei Trofimovich <slyich@gmail.com> Acked-by: Namhyung Kim <namhyung@kernel.org> Link: https://lore.kernel.org/r/20250505174419.2814857-1-slyich@gmail.com Signed-off-by: Namhyung Kim <namhyung@kernel.org>

Symbolize stack traces by creating a live machine. Add this functionality to dump_stack and switch dump_stack users to use it. Switch TUI to use it. Add stack traces to the child test function which can be useful to diagnose blocked code. Example output: ``` $ perf test -vv PERF_RECORD_ ... 7: PERF_RECORD_* events & perf_sample fields: 7: PERF_RECORD_* events & perf_sample fields : Running (1 active) ^C Signal (2) while running tests. Terminating tests with the same signal Internal test harness failure. Completing any started tests: : 7: PERF_RECORD_* events & perf_sample fields: ---- unexpected signal (2) ---- #0 0x55788c6210a3 in child_test_sig_handler builtin-test.c:0 #1 0x7fc12fe49df0 in __restore_rt libc_sigaction.c:0 #2 0x7fc12fe99687 in __internal_syscall_cancel cancellation.c:64 #3 0x7fc12fee5f7a in clock_nanosleep@GLIBC_2.2.5 clock_nanosleep.c:72 #4 0x7fc12fef1393 in __nanosleep nanosleep.c:26 #5 0x7fc12ff02d68 in __sleep sleep.c:55 #6 0x55788c63196b in test__PERF_RECORD perf-record.c:0 #7 0x55788c620fb0 in run_test_child builtin-test.c:0 #8 0x55788c5bd18d in start_command run-command.c:127 #9 0x55788c621ef3 in __cmd_test builtin-test.c:0 #10 0x55788c6225bf in cmd_test ??:0 #11 0x55788c5afbd0 in run_builtin perf.c:0 #12 0x55788c5afeeb in handle_internal_command perf.c:0 #13 0x55788c52b383 in main ??:0 #14 0x7fc12fe33ca8 in __libc_start_call_main libc_start_call_main.h:74 #15 0x7fc12fe33d65 in __libc_start_main@@GLIBC_2.34 libc-start.c:128 #16 0x55788c52b9d1 in _start ??:0 ---- unexpected signal (2) ---- #0 0x55788c6210a3 in child_test_sig_handler builtin-test.c:0 #1 0x7fc12fe49df0 in __restore_rt libc_sigaction.c:0 #2 0x7fc12fea3a14 in pthread_sigmask@GLIBC_2.2.5 pthread_sigmask.c:45 #3 0x7fc12fe49fd9 in __GI___sigprocmask sigprocmask.c:26 #4 0x7fc12ff2601b in __longjmp_chk longjmp.c:36 #5 0x55788c6210c0 in print_test_result.isra.0 builtin-test.c:0 #6 0x7fc12fe49df0 in __restore_rt libc_sigaction.c:0 #7 0x7fc12fe99687 in __internal_syscall_cancel cancellation.c:64 #8 0x7fc12fee5f7a in clock_nanosleep@GLIBC_2.2.5 clock_nanosleep.c:72 #9 0x7fc12fef1393 in __nanosleep nanosleep.c:26 #10 0x7fc12ff02d68 in __sleep sleep.c:55 #11 0x55788c63196b in test__PERF_RECORD perf-record.c:0 #12 0x55788c620fb0 in run_test_child builtin-test.c:0 #13 0x55788c5bd18d in start_command run-command.c:127 #14 0x55788c621ef3 in __cmd_test builtin-test.c:0 #15 0x55788c6225bf in cmd_test ??:0 #16 0x55788c5afbd0 in run_builtin perf.c:0 #17 0x55788c5afeeb in handle_internal_command perf.c:0 #18 0x55788c52b383 in main ??:0 #19 0x7fc12fe33ca8 in __libc_start_call_main libc_start_call_main.h:74 #20 0x7fc12fe33d65 in __libc_start_main@@GLIBC_2.34 libc-start.c:128 #21 0x55788c52b9d1 in _start ??:0 7: PERF_RECORD_* events & perf_sample fields : Skip (permissions) ``` Signed-off-by: Ian Rogers <irogers@google.com> Link: https://lore.kernel.org/r/20250624210500.2121303-1-irogers@google.com Signed-off-by: Namhyung Kim <namhyung@kernel.org>

Calling perf top with branch filters enabled on Intel CPU's with branch counters logging (A.K.A LBR event logging [1]) support results in a segfault. $ perf top -e '{cpu_core/cpu-cycles/,cpu_core/event=0xc6,umask=0x3,frontend=0x11,name=frontend_retired_dsb_miss/}' -j any,counter ... Thread 27 "perf" received signal SIGSEGV, Segmentation fault. [Switching to Thread 0x7fffafff76c0 (LWP 949003)] perf_env__find_br_cntr_info (env=0xf66dc0 <perf_env>, nr=0x0, width=0x7fffafff62c0) at util/env.c:653 653 *width = env->cpu_pmu_caps ? env->br_cntr_width : (gdb) bt #0 perf_env__find_br_cntr_info (env=0xf66dc0 <perf_env>, nr=0x0, width=0x7fffafff62c0) at util/env.c:653 #1 0x00000000005b1599 in symbol__account_br_cntr (branch=0x7fffcc3db580, evsel=0xfea2d0, offset=12, br_cntr=8) at util/annotate.c:345 #2 0x00000000005b17fb in symbol__account_cycles (addr=5658172, start=5658160, sym=0x7fffcc0ee420, cycles=539, evsel=0xfea2d0, br_cntr=8) at util/annotate.c:389 #3 0x00000000005b1976 in addr_map_symbol__account_cycles (ams=0x7fffcd7b01d0, start=0x7fffcd7b02b0, cycles=539, evsel=0xfea2d0, br_cntr=8) at util/annotate.c:422 #4 0x000000000068d57f in hist__account_cycles (bs=0x110d288, al=0x7fffafff6540, sample=0x7fffafff6760, nonany_branch_mode=false, total_cycles=0x0, evsel=0xfea2d0) at util/hist.c:2850 #5 0x0000000000446216 in hist_iter__top_callback (iter=0x7fffafff6590, al=0x7fffafff6540, single=true, arg=0x7fffffff9e00) at builtin-top.c:737 #6 0x0000000000689787 in hist_entry_iter__add (iter=0x7fffafff6590, al=0x7fffafff6540, max_stack_depth=127, arg=0x7fffffff9e00) at util/hist.c:1359 #7 0x0000000000446710 in perf_event__process_sample (tool=0x7fffffff9e00, event=0x110d250, evsel=0xfea2d0, sample=0x7fffafff6760, machine=0x108c968) at builtin-top.c:845 #8 0x0000000000447735 in deliver_event (qe=0x7fffffffa120, qevent=0x10fc200) at builtin-top.c:1211 #9 0x000000000064ccae in do_flush (oe=0x7fffffffa120, show_progress=false) at util/ordered-events.c:245 #10 0x000000000064d005 in __ordered_events__flush (oe=0x7fffffffa120, how=OE_FLUSH__TOP, timestamp=0) at util/ordered-events.c:324 #11 0x000000000064d0ef in ordered_events__flush (oe=0x7fffffffa120, how=OE_FLUSH__TOP) at util/ordered-events.c:342 #12 0x00000000004472a9 in process_thread (arg=0x7fffffff9e00) at builtin-top.c:1120 #13 0x00007ffff6e7dba8 in start_thread (arg=<optimized out>) at pthread_create.c:448 #14 0x00007ffff6f01b8c in __GI___clone3 () at ../sysdeps/unix/sysv/linux/x86_64/clone3.S:78 The cause is that perf_env__find_br_cntr_info tries to access a null pointer pmu_caps in the perf_env struct. A similar issue exists for homogeneous core systems which use the cpu_pmu_caps structure. Fix this by populating cpu_pmu_caps and pmu_caps structures with values from sysfs when calling perf top with branch stack sampling enabled. [1], LBR event logging introduced here: https://lore.kernel.org/all/20231025201626.3000228-5-kan.liang@linux.intel.com/ Reviewed-by: Ian Rogers <irogers@google.com> Signed-off-by: Thomas Falcon <thomas.falcon@intel.com> Link: https://lore.kernel.org/r/20250612163659.1357950-2-thomas.falcon@intel.com Signed-off-by: Namhyung Kim <namhyung@kernel.org>

Patch series "extend hung task blocker tracking to rwsems". Inspired by mutex blocker tracking[1], and having already extended it to semaphores, let's now add support for reader-writer semaphores (rwsems). The approach is simple: when a task enters TASK_UNINTERRUPTIBLE while waiting for an rwsem, we just call hung_task_set_blocker(). The hung task detector can then query the rwsem's owner to identify the lock holder. Tracking works reliably for writers, as there can only be a single writer holding the lock, and its task struct is stored in the owner field. The main challenge lies with readers. The owner field points to only one of many concurrent readers, so we might lose track of the blocker if that specific reader unlocks, even while others remain. This is not a significant issue, however. In practice, long-lasting lock contention is almost always caused by a writer. Therefore, reliably tracking the writer is the primary goal of this patch series ;) With this change, the hung task detector can now show blocker task's info like below: [Fri Jun 27 15:21:34 2025] INFO: task cat:28631 blocked for more than 122 seconds. [Fri Jun 27 15:21:34 2025] Tainted: G S 6.16.0-rc3 #8 [Fri Jun 27 15:21:34 2025] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. [Fri Jun 27 15:21:34 2025] task:cat state:D stack:0 pid:28631 tgid:28631 ppid:28501 task_flags:0x400000 flags:0x00004000 [Fri Jun 27 15:21:34 2025] Call Trace: [Fri Jun 27 15:21:34 2025] <TASK> [Fri Jun 27 15:21:34 2025] __schedule+0x7c7/0x1930 [Fri Jun 27 15:21:34 2025] ? __pfx___schedule+0x10/0x10 [Fri Jun 27 15:21:34 2025] ? policy_nodemask+0x215/0x340 [Fri Jun 27 15:21:34 2025] ? _raw_spin_lock_irq+0x8a/0xe0 [Fri Jun 27 15:21:34 2025] ? __pfx__raw_spin_lock_irq+0x10/0x10 [Fri Jun 27 15:21:34 2025] schedule+0x6a/0x180 [Fri Jun 27 15:21:34 2025] schedule_preempt_disabled+0x15/0x30 [Fri Jun 27 15:21:34 2025] rwsem_down_read_slowpath+0x55e/0xe10 [Fri Jun 27 15:21:34 2025] ? __pfx_rwsem_down_read_slowpath+0x10/0x10 [Fri Jun 27 15:21:34 2025] ? __pfx___might_resched+0x10/0x10 [Fri Jun 27 15:21:34 2025] down_read+0xc9/0x230 [Fri Jun 27 15:21:34 2025] ? __pfx_down_read+0x10/0x10 [Fri Jun 27 15:21:34 2025] ? __debugfs_file_get+0x14d/0x700 [Fri Jun 27 15:21:34 2025] ? __pfx___debugfs_file_get+0x10/0x10 [Fri Jun 27 15:21:34 2025] ? handle_pte_fault+0x52a/0x710 [Fri Jun 27 15:21:34 2025] ? selinux_file_permission+0x3a9/0x590 [Fri Jun 27 15:21:34 2025] read_dummy_rwsem_read+0x4a/0x90 [Fri Jun 27 15:21:34 2025] full_proxy_read+0xff/0x1c0 [Fri Jun 27 15:21:34 2025] ? rw_verify_area+0x6d/0x410 [Fri Jun 27 15:21:34 2025] vfs_read+0x177/0xa50 [Fri Jun 27 15:21:34 2025] ? __pfx_vfs_read+0x10/0x10 [Fri Jun 27 15:21:34 2025] ? fdget_pos+0x1cf/0x4c0 [Fri Jun 27 15:21:34 2025] ksys_read+0xfc/0x1d0 [Fri Jun 27 15:21:34 2025] ? __pfx_ksys_read+0x10/0x10 [Fri Jun 27 15:21:34 2025] do_syscall_64+0x66/0x2d0 [Fri Jun 27 15:21:34 2025] entry_SYSCALL_64_after_hwframe+0x76/0x7e [Fri Jun 27 15:21:34 2025] RIP: 0033:0x7f3f8faefb40 [Fri Jun 27 15:21:34 2025] RSP: 002b:00007ffdeda5ab98 EFLAGS: 00000246 ORIG_RAX: 0000000000000000 [Fri Jun 27 15:21:34 2025] RAX: ffffffffffffffda RBX: 0000000000010000 RCX: 00007f3f8faefb40 [Fri Jun 27 15:21:34 2025] RDX: 0000000000010000 RSI: 00000000010fa000 RDI: 0000000000000003 [Fri Jun 27 15:21:34 2025] RBP: 00000000010fa000 R08: 0000000000000000 R09: 0000000000010fff [Fri Jun 27 15:21:34 2025] R10: 00007ffdeda59fe0 R11: 0000000000000246 R12: 00000000010fa000 [Fri Jun 27 15:21:34 2025] R13: 0000000000000003 R14: 0000000000000000 R15: 0000000000000fff [Fri Jun 27 15:21:34 2025] </TASK> [Fri Jun 27 15:21:34 2025] INFO: task cat:28631 <reader> blocked on an rw-semaphore likely owned by task cat:28630 <writer> [Fri Jun 27 15:21:34 2025] task:cat state:S stack:0 pid:28630 tgid:28630 ppid:28501 task_flags:0x400000 flags:0x00004000 [Fri Jun 27 15:21:34 2025] Call Trace: [Fri Jun 27 15:21:34 2025] <TASK> [Fri Jun 27 15:21:34 2025] __schedule+0x7c7/0x1930 [Fri Jun 27 15:21:34 2025] ? __pfx___schedule+0x10/0x10 [Fri Jun 27 15:21:34 2025] ? __mod_timer+0x304/0xa80 [Fri Jun 27 15:21:34 2025] schedule+0x6a/0x180 [Fri Jun 27 15:21:34 2025] schedule_timeout+0xfb/0x230 [Fri Jun 27 15:21:34 2025] ? __pfx_schedule_timeout+0x10/0x10 [Fri Jun 27 15:21:34 2025] ? __pfx_process_timeout+0x10/0x10 [Fri Jun 27 15:21:34 2025] ? down_write+0xc4/0x140 [Fri Jun 27 15:21:34 2025] msleep_interruptible+0xbe/0x150 [Fri Jun 27 15:21:34 2025] read_dummy_rwsem_write+0x54/0x90 [Fri Jun 27 15:21:34 2025] full_proxy_read+0xff/0x1c0 [Fri Jun 27 15:21:34 2025] ? rw_verify_area+0x6d/0x410 [Fri Jun 27 15:21:34 2025] vfs_read+0x177/0xa50 [Fri Jun 27 15:21:34 2025] ? __pfx_vfs_read+0x10/0x10 [Fri Jun 27 15:21:34 2025] ? fdget_pos+0x1cf/0x4c0 [Fri Jun 27 15:21:34 2025] ksys_read+0xfc/0x1d0 [Fri Jun 27 15:21:34 2025] ? __pfx_ksys_read+0x10/0x10 [Fri Jun 27 15:21:34 2025] do_syscall_64+0x66/0x2d0 [Fri Jun 27 15:21:34 2025] entry_SYSCALL_64_after_hwframe+0x76/0x7e [Fri Jun 27 15:21:34 2025] RIP: 0033:0x7f8f288efb40 [Fri Jun 27 15:21:34 2025] RSP: 002b:00007ffffb631038 EFLAGS: 00000246 ORIG_RAX: 0000000000000000 [Fri Jun 27 15:21:34 2025] RAX: ffffffffffffffda RBX: 0000000000010000 RCX: 00007f8f288efb40 [Fri Jun 27 15:21:34 2025] RDX: 0000000000010000 RSI: 000000002a4b5000 RDI: 0000000000000003 [Fri Jun 27 15:21:34 2025] RBP: 000000002a4b5000 R08: 0000000000000000 R09: 0000000000010fff [Fri Jun 27 15:21:34 2025] R10: 00007ffffb630460 R11: 0000000000000246 R12: 000000002a4b5000 [Fri Jun 27 15:21:34 2025] R13: 0000000000000003 R14: 0000000000000000 R15: 0000000000000fff [Fri Jun 27 15:21:34 2025] </TASK> This patch (of 3): In preparation for extending blocker tracking to support rwsems, make the rwsem_owner() and is_rwsem_reader_owned() helpers globally available for determining if the blocker is a writer or one of the readers. Additionally, a stale owner pointer in a reader-owned rwsem can lead to false positives in blocker tracking when CONFIG_DETECT_HUNG_TASK_BLOCKER is enabled. To mitigate this, clear the owner field on the reader unlock path, similar to what CONFIG_DEBUG_RWSEMS does. A NULL owner is better than a stale one for diagnostics. Link: https://lkml.kernel.org/r/20250627072924.36567-1-lance.yang@linux.dev Link: https://lkml.kernel.org/r/20250627072924.36567-2-lance.yang@linux.dev Link: https://lore.kernel.org/all/174046694331.2194069.15472952050240807469.stgit@mhiramat.tok.corp.google.com/ [1] Signed-off-by: Lance Yang <lance.yang@linux.dev> Reviewed-by: Masami Hiramatsu (Google) <mhiramat@kernel.org> Cc: Anna Schumaker <anna.schumaker@oracle.com> Cc: Boqun Feng <boqun.feng@gmail.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Joel Granados <joel.granados@kernel.org> Cc: John Stultz <jstultz@google.com> Cc: Kent Overstreet <kent.overstreet@linux.dev> Cc: Mingzhe Yang <mingzhe.yang@ly.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Sergey Senozhatsky <senozhatsky@chromium.org> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Tomasz Figa <tfiga@chromium.org> Cc: Waiman Long <longman@redhat.com> Cc: Will Deacon <will@kernel.org> Cc: Yongliang Gao <leonylgao@tencent.com> Cc: Zi Li <zi.li@linux.dev> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

Inspired by mutex blocker tracking[1], and having already extended it to semaphores, let's now add support for reader-writer semaphores (rwsems). The approach is simple: when a task enters TASK_UNINTERRUPTIBLE while waiting for an rwsem, we just call hung_task_set_blocker(). The hung task detector can then query the rwsem's owner to identify the lock holder. Tracking works reliably for writers, as there can only be a single writer holding the lock, and its task struct is stored in the owner field. The main challenge lies with readers. The owner field points to only one of many concurrent readers, so we might lose track of the blocker if that specific reader unlocks, even while others remain. This is not a significant issue, however. In practice, long-lasting lock contention is almost always caused by a writer. Therefore, reliably tracking the writer is the primary goal of this patch series ;) With this change, the hung task detector can now show blocker task's info like below: [Fri Jun 27 15:21:34 2025] INFO: task cat:28631 blocked for more than 122 seconds. [Fri Jun 27 15:21:34 2025] Tainted: G S 6.16.0-rc3 #8 [Fri Jun 27 15:21:34 2025] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. [Fri Jun 27 15:21:34 2025] task:cat state:D stack:0 pid:28631 tgid:28631 ppid:28501 task_flags:0x400000 flags:0x00004000 [Fri Jun 27 15:21:34 2025] Call Trace: [Fri Jun 27 15:21:34 2025] <TASK> [Fri Jun 27 15:21:34 2025] __schedule+0x7c7/0x1930 [Fri Jun 27 15:21:34 2025] ? __pfx___schedule+0x10/0x10 [Fri Jun 27 15:21:34 2025] ? policy_nodemask+0x215/0x340 [Fri Jun 27 15:21:34 2025] ? _raw_spin_lock_irq+0x8a/0xe0 [Fri Jun 27 15:21:34 2025] ? __pfx__raw_spin_lock_irq+0x10/0x10 [Fri Jun 27 15:21:34 2025] schedule+0x6a/0x180 [Fri Jun 27 15:21:34 2025] schedule_preempt_disabled+0x15/0x30 [Fri Jun 27 15:21:34 2025] rwsem_down_read_slowpath+0x55e/0xe10 [Fri Jun 27 15:21:34 2025] ? __pfx_rwsem_down_read_slowpath+0x10/0x10 [Fri Jun 27 15:21:34 2025] ? __pfx___might_resched+0x10/0x10 [Fri Jun 27 15:21:34 2025] down_read+0xc9/0x230 [Fri Jun 27 15:21:34 2025] ? __pfx_down_read+0x10/0x10 [Fri Jun 27 15:21:34 2025] ? __debugfs_file_get+0x14d/0x700 [Fri Jun 27 15:21:34 2025] ? __pfx___debugfs_file_get+0x10/0x10 [Fri Jun 27 15:21:34 2025] ? handle_pte_fault+0x52a/0x710 [Fri Jun 27 15:21:34 2025] ? selinux_file_permission+0x3a9/0x590 [Fri Jun 27 15:21:34 2025] read_dummy_rwsem_read+0x4a/0x90 [Fri Jun 27 15:21:34 2025] full_proxy_read+0xff/0x1c0 [Fri Jun 27 15:21:34 2025] ? rw_verify_area+0x6d/0x410 [Fri Jun 27 15:21:34 2025] vfs_read+0x177/0xa50 [Fri Jun 27 15:21:34 2025] ? __pfx_vfs_read+0x10/0x10 [Fri Jun 27 15:21:34 2025] ? fdget_pos+0x1cf/0x4c0 [Fri Jun 27 15:21:34 2025] ksys_read+0xfc/0x1d0 [Fri Jun 27 15:21:34 2025] ? __pfx_ksys_read+0x10/0x10 [Fri Jun 27 15:21:34 2025] do_syscall_64+0x66/0x2d0 [Fri Jun 27 15:21:34 2025] entry_SYSCALL_64_after_hwframe+0x76/0x7e [Fri Jun 27 15:21:34 2025] RIP: 0033:0x7f3f8faefb40 [Fri Jun 27 15:21:34 2025] RSP: 002b:00007ffdeda5ab98 EFLAGS: 00000246 ORIG_RAX: 0000000000000000 [Fri Jun 27 15:21:34 2025] RAX: ffffffffffffffda RBX: 0000000000010000 RCX: 00007f3f8faefb40 [Fri Jun 27 15:21:34 2025] RDX: 0000000000010000 RSI: 00000000010fa000 RDI: 0000000000000003 [Fri Jun 27 15:21:34 2025] RBP: 00000000010fa000 R08: 0000000000000000 R09: 0000000000010fff [Fri Jun 27 15:21:34 2025] R10: 00007ffdeda59fe0 R11: 0000000000000246 R12: 00000000010fa000 [Fri Jun 27 15:21:34 2025] R13: 0000000000000003 R14: 0000000000000000 R15: 0000000000000fff [Fri Jun 27 15:21:34 2025] </TASK> [Fri Jun 27 15:21:34 2025] INFO: task cat:28631 <reader> blocked on an rw-semaphore likely owned by task cat:28630 <writer> [Fri Jun 27 15:21:34 2025] task:cat state:S stack:0 pid:28630 tgid:28630 ppid:28501 task_flags:0x400000 flags:0x00004000 [Fri Jun 27 15:21:34 2025] Call Trace: [Fri Jun 27 15:21:34 2025] <TASK> [Fri Jun 27 15:21:34 2025] __schedule+0x7c7/0x1930 [Fri Jun 27 15:21:34 2025] ? __pfx___schedule+0x10/0x10 [Fri Jun 27 15:21:34 2025] ? __mod_timer+0x304/0xa80 [Fri Jun 27 15:21:34 2025] schedule+0x6a/0x180 [Fri Jun 27 15:21:34 2025] schedule_timeout+0xfb/0x230 [Fri Jun 27 15:21:34 2025] ? __pfx_schedule_timeout+0x10/0x10 [Fri Jun 27 15:21:34 2025] ? __pfx_process_timeout+0x10/0x10 [Fri Jun 27 15:21:34 2025] ? down_write+0xc4/0x140 [Fri Jun 27 15:21:34 2025] msleep_interruptible+0xbe/0x150 [Fri Jun 27 15:21:34 2025] read_dummy_rwsem_write+0x54/0x90 [Fri Jun 27 15:21:34 2025] full_proxy_read+0xff/0x1c0 [Fri Jun 27 15:21:34 2025] ? rw_verify_area+0x6d/0x410 [Fri Jun 27 15:21:34 2025] vfs_read+0x177/0xa50 [Fri Jun 27 15:21:34 2025] ? __pfx_vfs_read+0x10/0x10 [Fri Jun 27 15:21:34 2025] ? fdget_pos+0x1cf/0x4c0 [Fri Jun 27 15:21:34 2025] ksys_read+0xfc/0x1d0 [Fri Jun 27 15:21:34 2025] ? __pfx_ksys_read+0x10/0x10 [Fri Jun 27 15:21:34 2025] do_syscall_64+0x66/0x2d0 [Fri Jun 27 15:21:34 2025] entry_SYSCALL_64_after_hwframe+0x76/0x7e [Fri Jun 27 15:21:34 2025] RIP: 0033:0x7f8f288efb40 [Fri Jun 27 15:21:34 2025] RSP: 002b:00007ffffb631038 EFLAGS: 00000246 ORIG_RAX: 0000000000000000 [Fri Jun 27 15:21:34 2025] RAX: ffffffffffffffda RBX: 0000000000010000 RCX: 00007f8f288efb40 [Fri Jun 27 15:21:34 2025] RDX: 0000000000010000 RSI: 000000002a4b5000 RDI: 0000000000000003 [Fri Jun 27 15:21:34 2025] RBP: 000000002a4b5000 R08: 0000000000000000 R09: 0000000000010fff [Fri Jun 27 15:21:34 2025] R10: 00007ffffb630460 R11: 0000000000000246 R12: 000000002a4b5000 [Fri Jun 27 15:21:34 2025] R13: 0000000000000003 R14: 0000000000000000 R15: 0000000000000fff [Fri Jun 27 15:21:34 2025] </TASK> [1] https://lore.kernel.org/all/174046694331.2194069.15472952050240807469.stgit@mhiramat.tok.corp.google.com/ Link: https://lkml.kernel.org/r/20250627072924.36567-3-lance.yang@linux.dev Signed-off-by: Lance Yang <lance.yang@linux.dev> Suggested-by: Masami Hiramatsu (Google) <mhiramat@kernel.org> Reviewed-by: Masami Hiramatsu (Google) <mhiramat@kernel.org> Cc: Anna Schumaker <anna.schumaker@oracle.com> Cc: Boqun Feng <boqun.feng@gmail.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Joel Granados <joel.granados@kernel.org> Cc: John Stultz <jstultz@google.com> Cc: Kent Overstreet <kent.overstreet@linux.dev> Cc: Mingzhe Yang <mingzhe.yang@ly.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Sergey Senozhatsky <senozhatsky@chromium.org> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Tomasz Figa <tfiga@chromium.org> Cc: Waiman Long <longman@redhat.com> Cc: Will Deacon <will@kernel.org> Cc: Yongliang Gao <leonylgao@tencent.com> Cc: Zi Li <zi.li@linux.dev> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

As syzbot [1] reported as below: R10: 0000000000000100 R11: 0000000000000206 R12: 00007ffe17473450 R13: 00007f28b1c10854 R14: 000000000000dae5 R15: 00007ffe17474520 </TASK> ---[ end trace 0000000000000000 ]--- ================================================================== BUG: KASAN: use-after-free in __list_del_entry_valid+0xa6/0x130 lib/list_debug.c:62 Read of size 8 at addr ffff88812d962278 by task syz-executor/564 CPU: 1 PID: 564 Comm: syz-executor Tainted: G W 6.1.129-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025 Call Trace: <TASK> __dump_stack+0x21/0x24 lib/dump_stack.c:88 dump_stack_lvl+0xee/0x158 lib/dump_stack.c:106 print_address_description+0x71/0x210 mm/kasan/report.c:316 print_report+0x4a/0x60 mm/kasan/report.c:427 kasan_report+0x122/0x150 mm/kasan/report.c:531 __asan_report_load8_noabort+0x14/0x20 mm/kasan/report_generic.c:351 __list_del_entry_valid+0xa6/0x130 lib/list_debug.c:62 __list_del_entry include/linux/list.h:134 [inline] list_del_init include/linux/list.h:206 [inline] f2fs_inode_synced+0xf7/0x2e0 fs/f2fs/super.c:1531 f2fs_update_inode+0x74/0x1c40 fs/f2fs/inode.c:585 f2fs_update_inode_page+0x137/0x170 fs/f2fs/inode.c:703 f2fs_write_inode+0x4ec/0x770 fs/f2fs/inode.c:731 write_inode fs/fs-writeback.c:1460 [inline] __writeback_single_inode+0x4a0/0xab0 fs/fs-writeback.c:1677 writeback_single_inode+0x221/0x8b0 fs/fs-writeback.c:1733 sync_inode_metadata+0xb6/0x110 fs/fs-writeback.c:2789 f2fs_sync_inode_meta+0x16d/0x2a0 fs/f2fs/checkpoint.c:1159 block_operations fs/f2fs/checkpoint.c:1269 [inline] f2fs_write_checkpoint+0xca3/0x2100 fs/f2fs/checkpoint.c:1658 kill_f2fs_super+0x231/0x390 fs/f2fs/super.c:4668 deactivate_locked_super+0x98/0x100 fs/super.c:332 deactivate_super+0xaf/0xe0 fs/super.c:363 cleanup_mnt+0x45f/0x4e0 fs/namespace.c:1186 __cleanup_mnt+0x19/0x20 fs/namespace.c:1193 task_work_run+0x1c6/0x230 kernel/task_work.c:203 exit_task_work include/linux/task_work.h:39 [inline] do_exit+0x9fb/0x2410 kernel/exit.c:871 do_group_exit+0x210/0x2d0 kernel/exit.c:1021 __do_sys_exit_group kernel/exit.c:1032 [inline] __se_sys_exit_group kernel/exit.c:1030 [inline] __x64_sys_exit_group+0x3f/0x40 kernel/exit.c:1030 x64_sys_call+0x7b4/0x9a0 arch/x86/include/generated/asm/syscalls_64.h:232 do_syscall_x64 arch/x86/entry/common.c:51 [inline] do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:81 entry_SYSCALL_64_after_hwframe+0x68/0xd2 RIP: 0033:0x7f28b1b8e169 Code: Unable to access opcode bytes at 0x7f28b1b8e13f. RSP: 002b:00007ffe174710a8 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7 RAX: ffffffffffffffda RBX: 00007f28b1c10879 RCX: 00007f28b1b8e169 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000001 RBP: 0000000000000002 R08: 00007ffe1746ee47 R09: 00007ffe17472360 R10: 0000000000000009 R11: 0000000000000246 R12: 00007ffe17472360 R13: 00007f28b1c10854 R14: 000000000000dae5 R15: 00007ffe17474520 </TASK> Allocated by task 569: kasan_save_stack mm/kasan/common.c:45 [inline] kasan_set_track+0x4b/0x70 mm/kasan/common.c:52 kasan_save_alloc_info+0x25/0x30 mm/kasan/generic.c:505 __kasan_slab_alloc+0x72/0x80 mm/kasan/common.c:328 kasan_slab_alloc include/linux/kasan.h:201 [inline] slab_post_alloc_hook+0x4f/0x2c0 mm/slab.h:737 slab_alloc_node mm/slub.c:3398 [inline] slab_alloc mm/slub.c:3406 [inline] __kmem_cache_alloc_lru mm/slub.c:3413 [inline] kmem_cache_alloc_lru+0x104/0x220 mm/slub.c:3429 alloc_inode_sb include/linux/fs.h:3245 [inline] f2fs_alloc_inode+0x2d/0x340 fs/f2fs/super.c:1419 alloc_inode fs/inode.c:261 [inline] iget_locked+0x186/0x880 fs/inode.c:1373 f2fs_iget+0x55/0x4c60 fs/f2fs/inode.c:483 f2fs_lookup+0x366/0xab0 fs/f2fs/namei.c:487 __lookup_slow+0x2a3/0x3d0 fs/namei.c:1690 lookup_slow+0x57/0x70 fs/namei.c:1707 walk_component+0x2e6/0x410 fs/namei.c:1998 lookup_last fs/namei.c:2455 [inline] path_lookupat+0x180/0x490 fs/namei.c:2479 filename_lookup+0x1f0/0x500 fs/namei.c:2508 vfs_statx+0x10b/0x660 fs/stat.c:229 vfs_fstatat fs/stat.c:267 [inline] vfs_lstat include/linux/fs.h:3424 [inline] __do_sys_newlstat fs/stat.c:423 [inline] __se_sys_newlstat+0xd5/0x350 fs/stat.c:417 __x64_sys_newlstat+0x5b/0x70 fs/stat.c:417 x64_sys_call+0x393/0x9a0 arch/x86/include/generated/asm/syscalls_64.h:7 do_syscall_x64 arch/x86/entry/common.c:51 [inline] do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:81 entry_SYSCALL_64_after_hwframe+0x68/0xd2 Freed by task 13: kasan_save_stack mm/kasan/common.c:45 [inline] kasan_set_track+0x4b/0x70 mm/kasan/common.c:52 kasan_save_free_info+0x31/0x50 mm/kasan/generic.c:516 ____kasan_slab_free+0x132/0x180 mm/kasan/common.c:236 __kasan_slab_free+0x11/0x20 mm/kasan/common.c:244 kasan_slab_free include/linux/kasan.h:177 [inline] slab_free_hook mm/slub.c:1724 [inline] slab_free_freelist_hook+0xc2/0x190 mm/slub.c:1750 slab_free mm/slub.c:3661 [inline] kmem_cache_free+0x12d/0x2a0 mm/slub.c:3683 f2fs_free_inode+0x24/0x30 fs/f2fs/super.c:1562 i_callback+0x4c/0x70 fs/inode.c:250 rcu_do_batch+0x503/0xb80 kernel/rcu/tree.c:2297 rcu_core+0x5a2/0xe70 kernel/rcu/tree.c:2557 rcu_core_si+0x9/0x10 kernel/rcu/tree.c:2574 handle_softirqs+0x178/0x500 kernel/softirq.c:578 run_ksoftirqd+0x28/0x30 kernel/softirq.c:945 smpboot_thread_fn+0x45a/0x8c0 kernel/smpboot.c:164 kthread+0x270/0x310 kernel/kthread.c:376 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295 Last potentially related work creation: kasan_save_stack+0x3a/0x60 mm/kasan/common.c:45 __kasan_record_aux_stack+0xb6/0xc0 mm/kasan/generic.c:486 kasan_record_aux_stack_noalloc+0xb/0x10 mm/kasan/generic.c:496 call_rcu+0xd4/0xf70 kernel/rcu/tree.c:2845 destroy_inode fs/inode.c:316 [inline] evict+0x7da/0x870 fs/inode.c:720 iput_final fs/inode.c:1834 [inline] iput+0x62b/0x830 fs/inode.c:1860 do_unlinkat+0x356/0x540 fs/namei.c:4397 __do_sys_unlink fs/namei.c:4438 [inline] __se_sys_unlink fs/namei.c:4436 [inline] __x64_sys_unlink+0x49/0x50 fs/namei.c:4436 x64_sys_call+0x958/0x9a0 arch/x86/include/generated/asm/syscalls_64.h:88 do_syscall_x64 arch/x86/entry/common.c:51 [inline] do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:81 entry_SYSCALL_64_after_hwframe+0x68/0xd2 The buggy address belongs to the object at ffff88812d961f20 which belongs to the cache f2fs_inode_cache of size 1200 The buggy address is located 856 bytes inside of 1200-byte region [ffff88812d961f20, ffff88812d9623d0) The buggy address belongs to the physical page: page:ffffea0004b65800 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x12d960 head:ffffea0004b65800 order:2 compound_mapcount:0 compound_pincount:0 flags: 0x4000000000010200(slab|head|zone=1) raw: 4000000000010200 0000000000000000 dead000000000122 ffff88810a94c500 raw: 0000000000000000 00000000800c000c 00000001ffffffff 0000000000000000 page dumped because: kasan: bad access detected page_owner tracks the page as allocated page last allocated via order 2, migratetype Reclaimable, gfp_mask 0x1d2050(__GFP_IO|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC|__GFP_HARDWALL|__GFP_RECLAIMABLE), pid 569, tgid 568 (syz.2.16), ts 55943246141, free_ts 0 set_page_owner include/linux/page_owner.h:31 [inline] post_alloc_hook+0x1d0/0x1f0 mm/page_alloc.c:2532 prep_new_page mm/page_alloc.c:2539 [inline] get_page_from_freelist+0x2e63/0x2ef0 mm/page_alloc.c:4328 __alloc_pages+0x235/0x4b0 mm/page_alloc.c:5605 alloc_slab_page include/linux/gfp.h:-1 [inline] allocate_slab mm/slub.c:1939 [inline] new_slab+0xec/0x4b0 mm/slub.c:1992 ___slab_alloc+0x6f6/0xb50 mm/slub.c:3180 __slab_alloc+0x5e/0xa0 mm/slub.c:3279 slab_alloc_node mm/slub.c:3364 [inline] slab_alloc mm/slub.c:3406 [inline] __kmem_cache_alloc_lru mm/slub.c:3413 [inline] kmem_cache_alloc_lru+0x13f/0x220 mm/slub.c:3429 alloc_inode_sb include/linux/fs.h:3245 [inline] f2fs_alloc_inode+0x2d/0x340 fs/f2fs/super.c:1419 alloc_inode fs/inode.c:261 [inline] iget_locked+0x186/0x880 fs/inode.c:1373 f2fs_iget+0x55/0x4c60 fs/f2fs/inode.c:483 f2fs_fill_super+0x3ad7/0x6bb0 fs/f2fs/super.c:4293 mount_bdev+0x2ae/0x3e0 fs/super.c:1443 f2fs_mount+0x34/0x40 fs/f2fs/super.c:4642 legacy_get_tree+0xea/0x190 fs/fs_context.c:632 vfs_get_tree+0x89/0x260 fs/super.c:1573 do_new_mount+0x25a/0xa20 fs/namespace.c:3056 page_owner free stack trace missing Memory state around the buggy address: ffff88812d962100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88812d962180: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff88812d962200: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff88812d962280: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88812d962300: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ================================================================== [1] https://syzkaller.appspot.com/x/report.txt?x=13448368580000 This bug can be reproduced w/ the reproducer [2], once we enable CONFIG_F2FS_CHECK_FS config, the reproducer will trigger panic as below, so the direct reason of this bug is the same as the one below patch [3] fixed. kernel BUG at fs/f2fs/inode.c:857! RIP: 0010:f2fs_evict_inode+0x1204/0x1a20 Call Trace: <TASK> evict+0x32a/0x7a0 do_unlinkat+0x37b/0x5b0 __x64_sys_unlink+0xad/0x100 do_syscall_64+0x5a/0xb0 entry_SYSCALL_64_after_hwframe+0x6e/0xd8 RIP: 0010:f2fs_evict_inode+0x1204/0x1a20 [2] https://syzkaller.appspot.com/x/repro.c?x=17495ccc580000 [3] https://lore.kernel.org/linux-f2fs-devel/20250702120321.1080759-1-chao@kernel.org Tracepoints before panic: f2fs_unlink_enter: dev = (7,0), dir ino = 3, i_size = 4096, i_blocks = 8, name = file1 f2fs_unlink_exit: dev = (7,0), ino = 7, ret = 0 f2fs_evict_inode: dev = (7,0), ino = 7, pino = 3, i_mode = 0x81ed, i_size = 10, i_nlink = 0, i_blocks = 0, i_advise = 0x0 f2fs_truncate_node: dev = (7,0), ino = 7, nid = 8, block_address = 0x3c05 f2fs_unlink_enter: dev = (7,0), dir ino = 3, i_size = 4096, i_blocks = 8, name = file3 f2fs_unlink_exit: dev = (7,0), ino = 8, ret = 0 f2fs_evict_inode: dev = (7,0), ino = 8, pino = 3, i_mode = 0x81ed, i_size = 9000, i_nlink = 0, i_blocks = 24, i_advise = 0x4 f2fs_truncate: dev = (7,0), ino = 8, pino = 3, i_mode = 0x81ed, i_size = 0, i_nlink = 0, i_blocks = 24, i_advise = 0x4 f2fs_truncate_blocks_enter: dev = (7,0), ino = 8, i_size = 0, i_blocks = 24, start file offset = 0 f2fs_truncate_blocks_exit: dev = (7,0), ino = 8, ret = -2 The root cause is: in the fuzzed image, dnode #8 belongs to inode #7, after inode #7 eviction, dnode #8 was dropped. However there is dirent that has ino #8, so, once we unlink file3, in f2fs_evict_inode(), both f2fs_truncate() and f2fs_update_inode_page() will fail due to we can not load node #8, result in we missed to call f2fs_inode_synced() to clear inode dirty status. Let's fix this by calling f2fs_inode_synced() in error path of f2fs_evict_inode(). PS: As I verified, the reproducer [2] can trigger this bug in v6.1.129, but it failed in v6.16-rc4, this is because the testcase will stop due to other corruption has been detected by f2fs: F2FS-fs (loop0): inconsistent node block, node_type:2, nid:8, node_footer[nid:8,ino:8,ofs:0,cpver:5013063228981249506,blkaddr:15366] F2FS-fs (loop0): f2fs_lookup: inode (ino=9) has zero i_nlink Fixes: 0f18b46 ("f2fs: flush inode metadata when checkpoint is doing") Closes: https://syzkaller.appspot.com/x/report.txt?x=13448368580000 Signed-off-by: Chao Yu <chao@kernel.org> Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

…tack-analysis' Eduard Zingerman says: ==================== bpf: replace path-sensitive with path-insensitive live stack analysis Consider the following program, assuming checkpoint is created for a state at instruction (3): 1: call bpf_get_prandom_u32() 2: *(u64 *)(r10 - 8) = 42 -- checkpoint #1 -- 3: if r0 != 0 goto +1 4: exit; 5: r0 = *(u64 *)(r10 - 8) 6: exit The verifier processes this program by exploring two paths: - 1 -> 2 -> 3 -> 4 - 1 -> 2 -> 3 -> 5 -> 6 When instruction (5) is processed, the current liveness tracking mechanism moves up the register parent links and records a "read" mark for stack slot -8 at checkpoint #1, stopping because of the "write" mark recorded at instruction (2). This patch set replaces the existing liveness tracking mechanism with a path-insensitive data flow analysis. The program above is processed as follows: - a data structure representing live stack slots for instructions 1-6 in frame #0 is allocated; - when instruction (2) is processed, record that slot -8 is written at instruction (2) in frame #0; - when instruction (5) is processed, record that slot -8 is read at instruction (5) in frame #0; - when instruction (6) is processed, propagate read mark for slot -8 up the control flow graph to instructions 3 and 2. The key difference is that the new mechanism operates on a control flow graph and associates read and write marks with pairs of (call chain, instruction index). In contrast, the old mechanism operates on verifier states and register parent links, associating read and write marks with verifier states. Motivation ========== As it stands, this patch set makes liveness tracking slightly less precise, as it no longer distinguishes individual program paths taken by the verifier during symbolic execution. See the "Impact on verification performance" section for details. However, this change is intended as a stepping stone toward the following goals: - Short term, integrate precision tracking into liveness analysis and remove the following code: - verifier backedge states accumulation in is_state_visited(); - most of the logic for precision tracking; - jump history tracking. - Long term, help with more efficient loop verification handling. Why integrating precision tracking? ----------------------------------- In a sense, precision tracking is very similar to liveness tracking. The data flow equations for liveness tracking look as follows: live_after = U [state[s].live_before for s in insn_successors(i)] state[i].live_before = (live_after / state[i].must_write) U state[i].may_read While data flow equations for precision tracking look as follows: precise_after = U [state[s].precise_before for s in insn_successors(i)] // if some of the instruction outputs are precise, // assume its inputs to be precise induced_precise = ⎧ state[i].may_read if (state[i].may_write ∩ precise_after) ≠ ∅ ⎨ ⎩ ∅ otherwise state[i].precise_before = (precise_after / state[i].must_write) ∩ induced_precise Where: - `may_read` set represents a union of all possibly read slots (any slot in `may_read` set might be by the instruction); - `must_write` set represents an intersection of all possibly written slots (any slot in `must_write` set is guaranteed to be written by the instruction). - `may_write` set represents a union of all possibly written slots (any slot in `may_write` set might be written by the instruction). This means that precision tracking can be implemented as a logical extension of liveness tracking: - track registers as well as stack slots; - add bit masks to represent `precise_before` and `may_write`; - add above equations for `precise_before` computation; - (linked registers require some additional consideration). Such extension would allow removal of: - precision propagation logic in verifier.c: - backtrack_insn() - mark_chain_precision() - propagate_{precision,backedges}() - push_jmp_history() and related data structures, which are only used by precision tracking; - add_scc_backedge() and related backedge state accumulation in is_state_visited(), superseded by per-callchain function state accumulated by liveness analysis. The hope here is that unifying liveness and precision tracking will reduce overall amount of code and make it easier to reason about. How this helps with loops? -------------------------- As it stands, this patch set shares the same deficiency as the current liveness tracking mechanism. Liveness marks on stack slots cannot be used to prune states when processing iterator-based loops: - such states still have branches to be explored; - meaning that not all stack slot reads have been discovered. For example: 1: while(iter_next()) { 2: if (...) 3: r0 = *(u64 *)(r10 - 8) 4: if (...) 5: r0 = *(u64 *)(r10 - 16) 6: ... 7: } For any checkpoint state created at instruction (1), it is only possible to rely on read marks for slots fp[-8] and fp[-16] once all child states of (1) have been explored. Thus, when the verifier transitions from (7) to (1), it cannot rely on read marks. However, sacrificing path-sensitivity makes it possible to run analysis defined in this patch set before main verification pass, if estimates for value ranges are available. E.g. for the following program: 1: while(iter_next()) { 2: r0 = r10 3: r0 += r2 4: r0 = *(u64 *)(r2 + 0) 5: ... 6: } If an estimate for `r2` range is available before the main verification pass, it can be used to populate read marks at instruction (4) and run the liveness analysis. Thus making conservative liveness information available during loops verification. Such estimates can be provided by some form of value range analysis. Value range analysis is also necessary to address loop verification from another angle: computing boundaries for loop induction variables and iteration counts. The hope here is that the new liveness tracking mechanism will support the broader goal of making loop verification more efficient. Validation ========== The change was tested on three program sets: - bpf selftests - sched_ext - Meta's internal set of programs Commit [#8] enables a special mode where both the current and new liveness analyses are enabled simultaneously. This mode signals an error if the new algorithm considers a stack slot dead while the current algorithm assumes it is alive. This mode was very useful for debugging. At the time of posting, no such errors have been reported for the above program sets. [#8] "bpf: signal error if old liveness is more conservative than new" Impact on memory consumption ============================ Debug patch [1] extends the kernel and veristat to count the amount of memory allocated for storing analysis data. This patch is not included in the submission. The maximal observed impact for the above program sets is 2.6Mb. Data below is shown in bytes. For bpf selftests top 5 consumers look as follows: File Program liveness mem ----------------------- ---------------- ------------ pyperf180.bpf.o on_event 2629740 pyperf600.bpf.o on_event 2287662 pyperf100.bpf.o on_event 1427022 test_verif_scale3.bpf.o balancer_ingress 1121283 pyperf_subprogs.bpf.o on_event 756900 For sched_ext top 5 consumers loog as follows: File Program liveness mem --------- ------------------------------- ------------ bpf.bpf.o lavd_enqueue 164686 bpf.bpf.o lavd_select_cpu 157393 bpf.bpf.o layered_enqueue 154817 bpf.bpf.o lavd_init 127865 bpf.bpf.o layered_dispatch 110129 For Meta's internal set of programs top consumer is 1Mb. [1] kernel-patches/bpf@085588e Impact on verification performance ================================== Veristat results below are reported using `-f insns_pct>1 -f !insns<500` filter and -t option (BPF_F_TEST_STATE_FREQ flag). master vs patch-set, selftests (out of ~4K programs) ---------------------------------------------------- File Program Insns (A) Insns (B) Insns (DIFF) -------------------------------- -------------------------------------- --------- --------- --------------- cpumask_success.bpf.o test_global_mask_nested_deep_array_rcu 1622 1655 +33 (+2.03%) strobemeta_bpf_loop.bpf.o on_event 2163 2684 +521 (+24.09%) test_cls_redirect.bpf.o cls_redirect 36001 42515 +6514 (+18.09%) test_cls_redirect_dynptr.bpf.o cls_redirect 2299 2339 +40 (+1.74%) test_cls_redirect_subprogs.bpf.o cls_redirect 69545 78497 +8952 (+12.87%) test_l4lb_noinline.bpf.o balancer_ingress 2993 3084 +91 (+3.04%) test_xdp_noinline.bpf.o balancer_ingress_v4 3539 3616 +77 (+2.18%) test_xdp_noinline.bpf.o balancer_ingress_v6 3608 3685 +77 (+2.13%) master vs patch-set, sched_ext (out of 148 programs) ---------------------------------------------------- File Program Insns (A) Insns (B) Insns (DIFF) --------- ---------------- --------- --------- --------------- bpf.bpf.o chaos_dispatch 2257 2287 +30 (+1.33%) bpf.bpf.o lavd_enqueue 20735 22101 +1366 (+6.59%) bpf.bpf.o lavd_select_cpu 22100 24409 +2309 (+10.45%) bpf.bpf.o layered_dispatch 25051 25606 +555 (+2.22%) bpf.bpf.o p2dq_dispatch 961 990 +29 (+3.02%) bpf.bpf.o rusty_quiescent 526 534 +8 (+1.52%) bpf.bpf.o rusty_runnable 541 547 +6 (+1.11%) Perf report =========== In relative terms, the analysis does not consume much CPU time. For example, here is a perf report collected for pyperf180 selftest: # Children Self Command Shared Object Symbol # ........ ........ ........ .................... ........................................ ... 1.22% 1.22% veristat [kernel.kallsyms] [k] bpf_update_live_stack ... Changelog ========= v1: https://lore.kernel.org/bpf/20250911010437.2779173-1-eddyz87@gmail.com/T/ v1 -> v2: - compute_postorder() fixed to handle jumps with offset -1 (syzbot). - is_state_visited() in patch #9 fixed access to uninitialized `err` (kernel test robot, Dan Carpenter). - Selftests added. - Fixed bug with write marks propagation from callee to caller, see verifier_live_stack.c:caller_stack_write() test case. - Added a patch for __not_msg() annotation for test_loader based tests. v2: https://lore.kernel.org/bpf/20250918-callchain-sensitive-liveness-v2-0-214ed2653eee@gmail.com/ v2 -> v3: - Added __diag_ignore_all("-Woverride-init", ...) in liveness.c for bpf_insn_successors() (suggested by Alexei). Signed-off-by: Eduard Zingerman <eddyz87@gmail.com> ==================== Link: https://patch.msgid.link/20250918-callchain-sensitive-liveness-v3-0-c3cd27bacc60@gmail.com Signed-off-by: Alexei Starovoitov <ast@kernel.org>

Before disabling SR-IOV via config space accesses to the parent PF, sriov_disable() first removes the PCI devices representing the VFs. Since commit 9d16947 ("PCI: Add global pci_lock_rescan_remove()") such removal operations are serialized against concurrent remove and rescan using the pci_rescan_remove_lock. No such locking was ever added in sriov_disable() however. In particular when commit 18f9e9d ("PCI/IOV: Factor out sriov_add_vfs()") factored out the PCI device removal into sriov_del_vfs() there was still no locking around the pci_iov_remove_virtfn() calls. On s390 the lack of serialization in sriov_disable() may cause double remove and list corruption with the below (amended) trace being observed: PSW: 0704c00180000000 0000000c914e4b38 (klist_put+56) GPRS: 000003800313fb48 0000000000000000 0000000100000001 0000000000000001 00000000f9b520a8 0000000000000000 0000000000002fbd 00000000f4cc9480 0000000000000001 0000000000000000 0000000000000000 0000000180692828 00000000818e8000 000003800313fe2c 000003800313fb20 000003800313fad8 #0 [3800313fb20] device_del at c9158ad5c #1 [3800313fb88] pci_remove_bus_device at c915105ba #2 [3800313fbd0] pci_iov_remove_virtfn at c9152f198 #3 [3800313fc28] zpci_iov_remove_virtfn at c90fb67c0 #4 [3800313fc60] zpci_bus_remove_device at c90fb6104 #5 [3800313fca0] __zpci_event_availability at c90fb3dca #6 [3800313fd08] chsc_process_sei_nt0 at c918fe4a2 #7 [3800313fd60] crw_collect_info at c91905822 #8 [3800313fe10] kthread at c90feb390 #9 [3800313fe68] __ret_from_fork at c90f6aa64 #10 [3800313fe98] ret_from_fork at c9194f3f2. This is because in addition to sriov_disable() removing the VFs, the platform also generates hot-unplug events for the VFs. This being the reverse operation to the hotplug events generated by sriov_enable() and handled via pdev->no_vf_scan. And while the event processing takes pci_rescan_remove_lock and checks whether the struct pci_dev still exists, the lack of synchronization makes this checking racy. Other races may also be possible of course though given that this lack of locking persisted so long observable races seem very rare. Even on s390 the list corruption was only observed with certain devices since the platform events are only triggered by config accesses after the removal, so as long as the removal finished synchronously they would not race. Either way the locking is missing so fix this by adding it to the sriov_del_vfs() helper. Just like PCI rescan-remove, locking is also missing in sriov_add_vfs() including for the error case where pci_stop_and_remove_bus_device() is called without the PCI rescan-remove lock being held. Even in the non-error case, adding new PCI devices and buses should be serialized via the PCI rescan-remove lock. Add the necessary locking. Fixes: 18f9e9d ("PCI/IOV: Factor out sriov_add_vfs()") Signed-off-by: Niklas Schnelle <schnelle@linux.ibm.com> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com> Reviewed-by: Benjamin Block <bblock@linux.ibm.com> Reviewed-by: Farhan Ali <alifm@linux.ibm.com> Reviewed-by: Julian Ruess <julianr@linux.ibm.com> Cc: stable@vger.kernel.org Link: https://patch.msgid.link/20250826-pci_fix_sriov_disable-v1-1-2d0bc938f2a3@linux.ibm.com

The test starts a workload and then opens events. If the events fail to open, for example because of perf_event_paranoid, the gopipe of the workload is leaked and the file descriptor leak check fails when the test exits. To avoid this cancel the workload when opening the events fails. Before: ``` $ perf test -vv 7 7: PERF_RECORD_* events & perf_sample fields: --- start --- test child forked, pid 1189568 Using CPUID GenuineIntel-6-B7-1 ------------------------------------------------------------ perf_event_attr: type 0 (PERF_TYPE_HARDWARE) config 0xa00000000 (cpu_atom/PERF_COUNT_HW_CPU_CYCLES/) disabled 1 ------------------------------------------------------------ sys_perf_event_open: pid 0 cpu -1 group_fd -1 flags 0x8 sys_perf_event_open failed, error -13 ------------------------------------------------------------ perf_event_attr: type 0 (PERF_TYPE_HARDWARE) config 0xa00000000 (cpu_atom/PERF_COUNT_HW_CPU_CYCLES/) disabled 1 exclude_kernel 1 ------------------------------------------------------------ sys_perf_event_open: pid 0 cpu -1 group_fd -1 flags 0x8 = 3 ------------------------------------------------------------ perf_event_attr: type 0 (PERF_TYPE_HARDWARE) config 0x400000000 (cpu_core/PERF_COUNT_HW_CPU_CYCLES/) disabled 1 ------------------------------------------------------------ sys_perf_event_open: pid 0 cpu -1 group_fd -1 flags 0x8 sys_perf_event_open failed, error -13 ------------------------------------------------------------ perf_event_attr: type 0 (PERF_TYPE_HARDWARE) config 0x400000000 (cpu_core/PERF_COUNT_HW_CPU_CYCLES/) disabled 1 exclude_kernel 1 ------------------------------------------------------------ sys_perf_event_open: pid 0 cpu -1 group_fd -1 flags 0x8 = 3 Attempt to add: software/cpu-clock/ ..after resolving event: software/config=0/ cpu-clock -> software/cpu-clock/ ------------------------------------------------------------ perf_event_attr: type 1 (PERF_TYPE_SOFTWARE) size 136 config 0x9 (PERF_COUNT_SW_DUMMY) sample_type IP|TID|TIME|CPU read_format ID|LOST disabled 1 inherit 1 mmap 1 comm 1 enable_on_exec 1 task 1 sample_id_all 1 mmap2 1 comm_exec 1 ksymbol 1 bpf_event 1 { wakeup_events, wakeup_watermark } 1 ------------------------------------------------------------ sys_perf_event_open: pid 1189569 cpu 0 group_fd -1 flags 0x8 sys_perf_event_open failed, error -13 perf_evlist__open: Permission denied ---- end(-2) ---- Leak of file descriptor 6 that opened: 'pipe:[14200347]' ---- unexpected signal (6) ---- iFailed to read build ID for //anon Failed to read build ID for //anon Failed to read build ID for //anon Failed to read build ID for //anon Failed to read build ID for //anon Failed to read build ID for //anon Failed to read build ID for //anon Failed to read build ID for //anon Failed to read build ID for //anon Failed to read build ID for //anon Failed to read build ID for //anon Failed to read build ID for //anon Failed to read build ID for //anon Failed to read build ID for //anon Failed to read build ID for //anon Failed to read build ID for //anon Failed to read build ID for //anon Failed to read build ID for //anon Failed to read build ID for //anon Failed to read build ID for //anon Failed to read build ID for //anon Failed to read build ID for //anon Failed to read build ID for //anon Failed to read build ID for //anon Failed to read build ID for //anon Failed to read build ID for //anon Failed to read build ID for //anon Failed to read build ID for //anon Failed to read build ID for //anon Failed to read build ID for //anon Failed to read build ID for //anon Failed to read build ID for //anon #0 0x565358f6666e in child_test_sig_handler builtin-test.c:311 #1 0x7f29ce849df0 in __restore_rt libc_sigaction.c:0 #2 0x7f29ce89e95c in __pthread_kill_implementation pthread_kill.c:44 #3 0x7f29ce849cc2 in raise raise.c:27 #4 0x7f29ce8324ac in abort abort.c:81 #5 0x565358f662d4 in check_leaks builtin-test.c:226 #6 0x565358f6682e in run_test_child builtin-test.c:344 #7 0x565358ef7121 in start_command run-command.c:128 #8 0x565358f67273 in start_test builtin-test.c:545 #9 0x565358f6771d in __cmd_test builtin-test.c:647 #10 0x565358f682bd in cmd_test builtin-test.c:849 #11 0x565358ee5ded in run_builtin perf.c:349 #12 0x565358ee6085 in handle_internal_command perf.c:401 #13 0x565358ee61de in run_argv perf.c:448 #14 0x565358ee6527 in main perf.c:555 #15 0x7f29ce833ca8 in __libc_start_call_main libc_start_call_main.h:74 #16 0x7f29ce833d65 in __libc_start_main@@GLIBC_2.34 libc-start.c:128 #17 0x565358e391c1 in _start perf[851c1] 7: PERF_RECORD_* events & perf_sample fields : FAILED! ``` After: ``` $ perf test 7 7: PERF_RECORD_* events & perf_sample fields : Skip (permissions) ``` Fixes: 16d00fe ("perf tests: Move test__PERF_RECORD into separate object") Signed-off-by: Ian Rogers <irogers@google.com> Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Adrian Hunter <adrian.hunter@intel.com> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Athira Rajeev <atrajeev@linux.ibm.com> Cc: Chun-Tse Shao <ctshao@google.com> Cc: Howard Chu <howardchu95@gmail.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: James Clark <james.clark@linaro.org> Cc: Jiri Olsa <jolsa@kernel.org> Cc: Kan Liang <kan.liang@linux.intel.com> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

[WHAT] IGT kms_cursor_legacy's long-nonblocking-modeset-vs-cursor-atomic fails with NULL pointer dereference. This can be reproduced with both an eDP panel and a DP monitors connected. BUG: kernel NULL pointer dereference, address: 0000000000000000 #PF: supervisor read access in kernel mode #PF: error_code(0x0000) - not-present page PGD 0 P4D 0 Oops: Oops: 0000 [#1] SMP NOPTI CPU: 13 UID: 0 PID: 2960 Comm: kms_cursor_lega Not tainted 6.16.0-99-custom #8 PREEMPT(voluntary) Hardware name: AMD ........ RIP: 0010:dc_stream_get_scanoutpos+0x34/0x130 [amdgpu] Code: 57 4d 89 c7 41 56 49 89 ce 41 55 49 89 d5 41 54 49 89 fc 53 48 83 ec 18 48 8b 87 a0 64 00 00 48 89 75 d0 48 c7 c6 e0 41 30 c2 <48> 8b 38 48 8b 9f 68 06 00 00 e8 8d d7 fd ff 31 c0 48 81 c3 e0 02 RSP: 0018:ffffd0f3c2bd7608 EFLAGS: 00010292 RAX: 0000000000000000 RBX: 0000000000000000 RCX: ffffd0f3c2bd7668 RDX: ffffd0f3c2bd7664 RSI: ffffffffc23041e0 RDI: ffff8b32494b8000 RBP: ffffd0f3c2bd7648 R08: ffffd0f3c2bd766c R09: ffffd0f3c2bd7760 R10: ffffd0f3c2bd7820 R11: 0000000000000000 R12: ffff8b32494b8000 R13: ffffd0f3c2bd7664 R14: ffffd0f3c2bd7668 R15: ffffd0f3c2bd766c FS: 000071f631b68700(0000) GS:ffff8b399f114000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000000000000 CR3: 00000001b8105000 CR4: 0000000000f50ef0 PKRU: 55555554 Call Trace: <TASK> dm_crtc_get_scanoutpos+0xd7/0x180 [amdgpu] amdgpu_display_get_crtc_scanoutpos+0x86/0x1c0 [amdgpu] ? __pfx_amdgpu_crtc_get_scanout_position+0x10/0x10[amdgpu] amdgpu_crtc_get_scanout_position+0x27/0x50 [amdgpu] drm_crtc_vblank_helper_get_vblank_timestamp_internal+0xf7/0x400 drm_crtc_vblank_helper_get_vblank_timestamp+0x1c/0x30 drm_crtc_get_last_vbltimestamp+0x55/0x90 drm_crtc_next_vblank_start+0x45/0xa0 drm_atomic_helper_wait_for_fences+0x81/0x1f0 ... Cc: Mario Limonciello <mario.limonciello@amd.com> Cc: Alex Deucher <alexander.deucher@amd.com> Reviewed-by: Aurabindo Pillai <aurabindo.pillai@amd.com> Signed-off-by: Alex Hung <alex.hung@amd.com> Signed-off-by: Alex Deucher <alexander.deucher@amd.com> (cherry picked from commit 621e55f) Cc: stable@vger.kernel.org

When the system has many cores and task switching is frequent, setting set_ftrace_pid can cause frequent pid_list->lock contention and high system sys usage. For example, in a 288-core VM environment, we observed 267 CPUs experiencing contention on pid_list->lock, with stack traces showing: #4 [ffffa6226fb4bc70] native_queued_spin_lock_slowpath at ffffffff99cd4b7e #5 [ffffa6226fb4bc90] _raw_spin_lock_irqsave at ffffffff99cd3e36 #6 [ffffa6226fb4bca0] trace_pid_list_is_set at ffffffff99267554 #7 [ffffa6226fb4bcc0] trace_ignore_this_task at ffffffff9925c288 #8 [ffffa6226fb4bcd8] ftrace_filter_pid_sched_switch_probe at ffffffff99246efe #9 [ffffa6226fb4bcf0] __schedule at ffffffff99ccd161 Replaces the existing spinlock with a seqlock to allow concurrent readers, while maintaining write exclusivity. Link: https://patch.msgid.link/20251113000252.1058144-1-leonylgao@gmail.com Reviewed-by: Huang Cun <cunhuang@tencent.com> Signed-off-by: Yongliang Gao <leonylgao@tencent.com> Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>

… 'T' When perf report with annotation for a symbol, press 's' and 'T', then exit the annotate browser. Once annotate the same symbol, the annotate browser will crash. The browser.arch was required to be correctly updated when data type feature was enabled by 'T'. Usually it was initialized by symbol__annotate2 function. If a symbol has already been correctly annotated at the first time, it should not call the symbol__annotate2 function again, thus the browser.arch will not get initialized. Then at the second time to show the annotate browser, the data type needs to be displayed but the browser.arch is empty. Stack trace as below: Perf: Segmentation fault -------- backtrace -------- #0 0x55d365 in ui__signal_backtrace setup.c:0 #1 0x7f5ff1a3e930 in __restore_rt libc.so.6[3e930] #2 0x570f08 in arch__is perf[570f08] #3 0x562186 in annotate_get_insn_location perf[562186] #4 0x562626 in __hist_entry__get_data_type annotate.c:0 #5 0x56476d in annotation_line__write perf[56476d] #6 0x54e2db in annotate_browser__write annotate.c:0 #7 0x54d061 in ui_browser__list_head_refresh perf[54d061] #8 0x54dc9e in annotate_browser__refresh annotate.c:0 #9 0x54c03d in __ui_browser__refresh browser.c:0 #10 0x54ccf8 in ui_browser__run perf[54ccf8] #11 0x54eb92 in __hist_entry__tui_annotate perf[54eb92] #12 0x552293 in do_annotate hists.c:0 #13 0x55941c in evsel__hists_browse hists.c:0 #14 0x55b00f in evlist__tui_browse_hists perf[55b00f] #15 0x42ff02 in cmd_report perf[42ff02] #16 0x494008 in run_builtin perf.c:0 #17 0x494305 in handle_internal_command perf.c:0 #18 0x410547 in main perf[410547] #19 0x7f5ff1a295d0 in __libc_start_call_main libc.so.6[295d0] #20 0x7f5ff1a29680 in __libc_start_main@@GLIBC_2.34 libc.so.6[29680] #21 0x410b75 in _start perf[410b75] Fixes: 1d4374a ("perf annotate: Add 'T' hot key to toggle data type display") Reviewed-by: James Clark <james.clark@linaro.org> Tested-by: Namhyung Kim <namhyung@kernel.org> Signed-off-by: Tianyou Li <tianyou.li@intel.com> Signed-off-by: Namhyung Kim <namhyung@kernel.org>

When using perf record with the `--overwrite` option, a segmentation fault occurs if an event fails to open. For example: perf record -e cycles-ct -F 1000 -a --overwrite Error: cycles-ct:H: PMU Hardware doesn't support sampling/overflow-interrupts. Try 'perf stat' perf: Segmentation fault #0 0x6466b6 in dump_stack debug.c:366 #1 0x646729 in sighandler_dump_stack debug.c:378 #2 0x453fd1 in sigsegv_handler builtin-record.c:722 #3 0x7f8454e65090 in __restore_rt libc-2.32.so[54090] #4 0x6c5671 in __perf_event__synthesize_id_index synthetic-events.c:1862 #5 0x6c5ac0 in perf_event__synthesize_id_index synthetic-events.c:1943 #6 0x458090 in record__synthesize builtin-record.c:2075 #7 0x45a85a in __cmd_record builtin-record.c:2888 #8 0x45deb6 in cmd_record builtin-record.c:4374 #9 0x4e5e33 in run_builtin perf.c:349 #10 0x4e60bf in handle_internal_command perf.c:401 #11 0x4e6215 in run_argv perf.c:448 #12 0x4e653a in main perf.c:555 #13 0x7f8454e4fa72 in __libc_start_main libc-2.32.so[3ea72] #14 0x43a3ee in _start ??:0 The --overwrite option implies --tail-synthesize, which collects non-sample events reflecting the system status when recording finishes. However, when evsel opening fails (e.g., unsupported event 'cycles-ct'), session->evlist is not initialized and remains NULL. The code unconditionally calls record__synthesize() in the error path, which iterates through the NULL evlist pointer and causes a segfault. To fix it, move the record__synthesize() call inside the error check block, so it's only called when there was no error during recording, ensuring that evlist is properly initialized. Fixes: 4ea648a ("perf record: Add --tail-synthesize option") Signed-off-by: Shuai Xue <xueshuai@linux.alibaba.com> Signed-off-by: Namhyung Kim <namhyung@kernel.org>

When interrupting perf stat in repeat mode with a signal the signal is passed to the child process but the repeat doesn't terminate: ``` $ perf stat -v --null --repeat 10 sleep 1 Control descriptor is not initialized [ perf stat: executing run #1 ... ] [ perf stat: executing run #2 ... ] ^Csleep: Interrupt [ perf stat: executing run #3 ... ] [ perf stat: executing run #4 ... ] [ perf stat: executing run #5 ... ] [ perf stat: executing run #6 ... ] [ perf stat: executing run #7 ... ] [ perf stat: executing run #8 ... ] [ perf stat: executing run #9 ... ] [ perf stat: executing run #10 ... ] Performance counter stats for 'sleep 1' (10 runs): 0.9500 +- 0.0512 seconds time elapsed ( +- 5.39% ) 0.01user 0.02system 0:09.53elapsed 0%CPU (0avgtext+0avgdata 18940maxresident)k 29944inputs+0outputs (0major+2629minor)pagefaults 0swaps ``` Terminate the repeated run and give a reasonable exit value: ``` $ perf stat -v --null --repeat 10 sleep 1 Control descriptor is not initialized [ perf stat: executing run #1 ... ] [ perf stat: executing run #2 ... ] [ perf stat: executing run #3 ... ] ^Csleep: Interrupt Performance counter stats for 'sleep 1' (10 runs): 0.680 +- 0.321 seconds time elapsed ( +- 47.16% ) Command exited with non-zero status 130 0.00user 0.01system 0:02.05elapsed 0%CPU (0avgtext+0avgdata 70688maxresident)k 0inputs+0outputs (0major+5002minor)pagefaults 0swaps ``` Note, this also changes the exit value for non-repeat runs when interrupted by a signal. Reported-by: Ingo Molnar <mingo@kernel.org> Closes: https://lore.kernel.org/lkml/aS5wjmbAM9ka3M2g@gmail.com/ Signed-off-by: Ian Rogers <irogers@google.com> Tested-by: Thomas Richter <tmricht@linux.ibm.com> Signed-off-by: Namhyung Kim <namhyung@kernel.org>

bergwolf added 4 commits June 5, 2013 17:38

staging/lustre/ldlm: convert to shrinkers to count/scan API

df48ce3

convert ldlm shrinker to new count/scan API. Signed-off-by: Peng Tao <tao.peng@emc.com>

staging/lustre/obdclass: convert lu_object shrinker to count/scan API

9b1794a

convert lu_object shrinker to new count/scan API. Signed-off-by: Peng Tao <tao.peng@emc.com>

staging/lustre/ptlrpc: convert to new shrinker API

4c0370f

Convert sptlrpc encode pool shrinker to use scan/count API. Signed-off-by: Peng Tao <tao.peng@emc.com>

staging/lustre/libcfs: cleanup linux-mem.h

f3479ea

remove shrinker related wrappers. Signed-off-by: Peng Tao <tao.peng@emc.com>

bergwolf closed this Oct 29, 2013

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bergwolf commented Jun 5, 2013

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