Updated README for MarkDown (This is not a final version but a draft). #16

ghost · 2012-03-29T15:33:54Z

This is a MarkDown version of the README file... must be renamed to README.md to work properly (I think).

ghost · 2012-03-29T15:37:00Z

README

Someone necessarily lend a hand to make critically posts I might state. That is the first time I frequented your website page and thus far? I amazed with the analysis you made to make this actual put up extraordinary. Fantastic task!
Comprar Nike Air Max Baratas http://sofos.scsalud.es/fondosDoc/Farmacia/AIR/comprar-nike-air-max-baratas.cfm

…S block during isolation for migration commit 0bf380b upstream. When isolating for migration, migration starts at the start of a zone which is not necessarily pageblock aligned. Further, it stops isolating when COMPACT_CLUSTER_MAX pages are isolated so migrate_pfn is generally not aligned. This allows isolate_migratepages() to call pfn_to_page() on an invalid PFN which can result in a crash. This was originally reported against a 3.0-based kernel with the following trace in a crash dump. PID: 9902 TASK: d47aecd0 CPU: 0 COMMAND: "memcg_process_s" #0 [d72d3ad0] crash_kexec at c028cfdb #1 [d72d3b24] oops_end at c05c5322 #2 [d72d3b38] __bad_area_nosemaphore at c0227e60 #3 [d72d3bec] bad_area at c0227fb6 #4 [d72d3c00] do_page_fault at c05c72e #5 [d72d3c80] error_code (via page_fault) at c05c47a4 EAX: 00000000 EBX: 000c0000 ECX: 00000001 EDX: 00000807 EBP: 000c0000 DS: 007b ESI: 00000001 ES: 007b EDI: f3000a80 GS: 6f50 CS: 0060 EIP: c030b15a ERR: ffffffff EFLAGS: 00010002 #6 [d72d3cb4] isolate_migratepages at c030b15a #7 [d72d3d14] zone_watermark_ok at c02d26cb #8 [d72d3d2c] compact_zone at c030b8d #9 [d72d3d68] compact_zone_order at c030bba1 torvalds#10 [d72d3db4] try_to_compact_pages at c030bc84 torvalds#11 [d72d3ddc] __alloc_pages_direct_compact at c02d61e7 torvalds#12 [d72d3e08] __alloc_pages_slowpath at c02d66c7 torvalds#13 [d72d3e78] __alloc_pages_nodemask at c02d6a97 torvalds#14 [d72d3eb8] alloc_pages_vma at c030a845 torvalds#15 [d72d3ed4] do_huge_pmd_anonymous_page at c03178eb torvalds#16 [d72d3f00] handle_mm_fault at c02f36c6 torvalds#17 [d72d3f30] do_page_fault at c05c70ed torvalds#18 [d72d3fb] error_code (via page_fault) at c05c47a4 EAX: b71ff000 EBX: 00000001 ECX: 00001600 EDX: 00000431 DS: 007b ESI: 08048950 ES: 007b EDI: bfaa3788 SS: 007b ESP: bfaa36e0 EBP: bfaa3828 GS: 6f50 CS: 0073 EIP: 080487c8 ERR: ffffffff EFLAGS: 00010202 It was also reported by Herbert van den Bergh against 3.1-based kernel with the following snippet from the console log. BUG: unable to handle kernel paging request at 01c00008 IP: [<c0522399>] isolate_migratepages+0x119/0x390 *pdpt = 000000002f7ce001 *pde = 0000000000000000 It is expected that it also affects 3.2.x and current mainline. The problem is that pfn_valid is only called on the first PFN being checked and that PFN is not necessarily aligned. Lets say we have a case like this H = MAX_ORDER_NR_PAGES boundary | = pageblock boundary m = cc->migrate_pfn f = cc->free_pfn o = memory hole H------|------H------|----m-Hoooooo|ooooooH-f----|------H The migrate_pfn is just below a memory hole and the free scanner is beyond the hole. When isolate_migratepages started, it scans from migrate_pfn to migrate_pfn+pageblock_nr_pages which is now in a memory hole. It checks pfn_valid() on the first PFN but then scans into the hole where there are not necessarily valid struct pages. This patch ensures that isolate_migratepages calls pfn_valid when necessary. Reported-by: Herbert van den Bergh <herbert.van.den.bergh@oracle.com> Tested-by: Herbert van den Bergh <herbert.van.den.bergh@oracle.com> Signed-off-by: Mel Gorman <mgorman@suse.de> Acked-by: Michal Nazarewicz <mina86@mina86.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Printing the "start_ip" for every secondary cpu is very noisy on a large system - and doesn't add any value. Drop this message. Console log before: Booting Node 0, Processors #1 smpboot cpu 1: start_ip = 96000 #2 smpboot cpu 2: start_ip = 96000 #3 smpboot cpu 3: start_ip = 96000 #4 smpboot cpu 4: start_ip = 96000 ... torvalds#31 smpboot cpu 31: start_ip = 96000 Brought up 32 CPUs Console log after: Booting Node 0, Processors #1 #2 #3 #4 #5 torvalds#6 torvalds#7 Ok. Booting Node 1, Processors torvalds#8 torvalds#9 torvalds#10 torvalds#11 torvalds#12 torvalds#13 torvalds#14 torvalds#15 Ok. Booting Node 0, Processors torvalds#16 torvalds#17 torvalds#18 torvalds#19 torvalds#20 torvalds#21 torvalds#22 torvalds#23 Ok. Booting Node 1, Processors torvalds#24 torvalds#25 torvalds#26 torvalds#27 torvalds#28 torvalds#29 torvalds#30 torvalds#31 Brought up 32 CPUs Acked-by: Borislav Petkov <bp@amd64.org> Signed-off-by: Tony Luck <tony.luck@intel.com> Link: http://lkml.kernel.org/r/4f452eb42507460426@agluck-desktop.sc.intel.com Signed-off-by: H. Peter Anvin <hpa@zytor.com>

Add a parameter to avoid using MSI/MSI-X for PCIe native hotplug; it's known to be buggy on some platforms. In my environment, while shutting down, following stack trace is shown sometimes. irq 16: nobody cared (try booting with the "irqpoll" option) Pid: 1081, comm: reboot Not tainted 3.2.0 #1 Call Trace: <IRQ> [<ffffffff810cec1d>] __report_bad_irq+0x3d/0xe0 [<ffffffff810cee1c>] note_interrupt+0x15c/0x210 [<ffffffff810cc485>] handle_irq_event_percpu+0xb5/0x210 [<ffffffff810cc621>] handle_irq_event+0x41/0x70 [<ffffffff810cf675>] handle_fasteoi_irq+0x55/0xc0 [<ffffffff81015356>] handle_irq+0x46/0xb0 [<ffffffff814fbe9d>] do_IRQ+0x5d/0xe0 [<ffffffff814f146e>] common_interrupt+0x6e/0x6e [<ffffffff8106b040>] ? __do_softirq+0x60/0x210 [<ffffffff8108aeb1>] ? hrtimer_interrupt+0x151/0x240 [<ffffffff814fb5ec>] call_softirq+0x1c/0x30 [<ffffffff810152d5>] do_softirq+0x65/0xa0 [<ffffffff8106ae9d>] irq_exit+0xbd/0xe0 [<ffffffff814fbf8e>] smp_apic_timer_interrupt+0x6e/0x99 [<ffffffff814f9e5e>] apic_timer_interrupt+0x6e/0x80 <EOI> [<ffffffff814f0fb1>] ? _raw_spin_unlock_irqrestore+0x11/0x20 [<ffffffff812629fc>] pci_bus_write_config_word+0x6c/0x80 [<ffffffff81266fc2>] pci_intx+0x52/0xa0 [<ffffffff8127de3d>] pci_intx_for_msi+0x1d/0x30 [<ffffffff8127e4fb>] pci_msi_shutdown+0x7b/0x110 [<ffffffff81269d34>] pci_device_shutdown+0x34/0x50 [<ffffffff81326c4f>] device_shutdown+0x2f/0x140 [<ffffffff8107b981>] kernel_restart_prepare+0x31/0x40 [<ffffffff8107b9e6>] kernel_restart+0x16/0x60 [<ffffffff8107bbfd>] sys_reboot+0x1ad/0x220 [<ffffffff814f4b90>] ? do_page_fault+0x1e0/0x460 [<ffffffff811942d0>] ? __sync_filesystem+0x90/0x90 [<ffffffff8105c9aa>] ? __cond_resched+0x2a/0x40 [<ffffffff814ef090>] ? _cond_resched+0x30/0x40 [<ffffffff81169e17>] ? iterate_supers+0xb7/0xd0 [<ffffffff814f9382>] system_call_fastpath+0x16/0x1b handlers: [<ffffffff8138a0f0>] usb_hcd_irq [<ffffffff8138a0f0>] usb_hcd_irq [<ffffffff8138a0f0>] usb_hcd_irq Disabling IRQ torvalds#16 An un-wanted interrupt is generated when PCI driver switches from MSI/MSI-X to INTx while shutting down the device. The interrupt does not happen if MSI/MSI-X is not used on the device. I confirmed that this problem does not happen if pcie_hp=nomsi was specified and hotplug operation worked fine as usual. v2: Automatically disable MSI/MSI-X against following device: PCI bridge: Integrated Device Technology, Inc. Device 807f (rev 02) v3: Based on the review comment, combile the if statements. v4: Removed module parameter. Move some code to build pciehp as a module. Move device specific code to driver/pci/quirks.c. v5: Drop a device specific code until getting a vendor statement. Reviewed-by: Kenji Kaneshige <kaneshige.kenji@jp.fujitsu.com> Signed-off-by: MUNEDA Takahiro <muneda.takahiro@jp.fujitsu.com> Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>

Vivek reported a kernel crash: [ 94.217015] BUG: unable to handle kernel NULL pointer dereference at 000000000000001c [ 94.218004] IP: [<ffffffff81142fae>] kmem_cache_free+0x5e/0x200 [ 94.218004] PGD 13abda067 PUD 137d52067 PMD 0 [ 94.218004] Oops: 0000 [#1] SMP DEBUG_PAGEALLOC [ 94.218004] CPU 0 [ 94.218004] Modules linked in: [last unloaded: scsi_wait_scan] [ 94.218004] [ 94.218004] Pid: 0, comm: swapper/0 Not tainted 3.2.0+ torvalds#16 Hewlett-Packard HP xw6600 Workstation/0A9Ch [ 94.218004] RIP: 0010:[<ffffffff81142fae>] [<ffffffff81142fae>] kmem_cache_free+0x5e/0x200 [ 94.218004] RSP: 0018:ffff88013fc03de0 EFLAGS: 00010006 [ 94.218004] RAX: ffffffff81e0d020 RBX: ffff880138b3c680 RCX: 00000001801c001b [ 94.218004] RDX: 00000000003aac1d RSI: ffff880138b3c680 RDI: ffffffff81142fae [ 94.218004] RBP: ffff88013fc03e10 R08: ffff880137830238 R09: 0000000000000001 [ 94.218004] R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000 [ 94.218004] R13: ffffea0004e2cf00 R14: ffffffff812f6eb6 R15: 0000000000000246 [ 94.218004] FS: 0000000000000000(0000) GS:ffff88013fc00000(0000) knlGS:0000000000000000 [ 94.218004] CS: 0010 DS: 0000 ES: 0000 CR0: 000000008005003b [ 94.218004] CR2: 000000000000001c CR3: 00000001395ab000 CR4: 00000000000006f0 [ 94.218004] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [ 94.218004] DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400 [ 94.218004] Process swapper/0 (pid: 0, threadinfo ffffffff81e00000, task ffffffff81e0d020) [ 94.218004] Stack: [ 94.218004] 0000000000000102 ffff88013fc0db20 ffffffff81e22700 ffff880139500f00 [ 94.218004] 0000000000000001 000000000000000a ffff88013fc03e20 ffffffff812f6eb6 [ 94.218004] ffff88013fc03e90 ffffffff810c8da2 ffffffff81e01fd8 ffff880137830240 [ 94.218004] Call Trace: [ 94.218004] <IRQ> [ 94.218004] [<ffffffff812f6eb6>] icq_free_icq_rcu+0x16/0x20 [ 94.218004] [<ffffffff810c8da2>] __rcu_process_callbacks+0x1c2/0x420 [ 94.218004] [<ffffffff810c9038>] rcu_process_callbacks+0x38/0x250 [ 94.218004] [<ffffffff810405ee>] __do_softirq+0xce/0x3e0 [ 94.218004] [<ffffffff8108ed04>] ? clockevents_program_event+0x74/0x100 [ 94.218004] [<ffffffff81090104>] ? tick_program_event+0x24/0x30 [ 94.218004] [<ffffffff8183ed1c>] call_softirq+0x1c/0x30 [ 94.218004] [<ffffffff8100422d>] do_softirq+0x8d/0xc0 [ 94.218004] [<ffffffff81040c3e>] irq_exit+0xae/0xe0 [ 94.218004] [<ffffffff8183f4be>] smp_apic_timer_interrupt+0x6e/0x99 [ 94.218004] [<ffffffff8183e330>] apic_timer_interrupt+0x70/0x80 Once a queue is quiesced, it's not supposed to have any elvpriv data or icq's, and elevator switching depends on that. Request alloc path followed the rule for elvpriv data but forgot apply it to icq's leading to the following crash during elevator switch. Fix it by not allocating icq's if ELVPRIV is not set for the request. Reported-by: Vivek Goyal <vgoyal@redhat.com> Tested-by: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Shaohua Li <shaohua.li@intel.com> Acked-by: Tejun Heo <tj@kernel.org> Signed-off-by: Jens Axboe <axboe@kernel.dk>

…S block during isolation for migration When isolating for migration, migration starts at the start of a zone which is not necessarily pageblock aligned. Further, it stops isolating when COMPACT_CLUSTER_MAX pages are isolated so migrate_pfn is generally not aligned. This allows isolate_migratepages() to call pfn_to_page() on an invalid PFN which can result in a crash. This was originally reported against a 3.0-based kernel with the following trace in a crash dump. PID: 9902 TASK: d47aecd0 CPU: 0 COMMAND: "memcg_process_s" #0 [d72d3ad0] crash_kexec at c028cfdb #1 [d72d3b24] oops_end at c05c5322 #2 [d72d3b38] __bad_area_nosemaphore at c0227e60 #3 [d72d3bec] bad_area at c0227fb6 #4 [d72d3c00] do_page_fault at c05c72e #5 [d72d3c80] error_code (via page_fault) at c05c47a4 EAX: 00000000 EBX: 000c0000 ECX: 00000001 EDX: 00000807 EBP: 000c0000 DS: 007b ESI: 00000001 ES: 007b EDI: f3000a80 GS: 6f50 CS: 0060 EIP: c030b15a ERR: ffffffff EFLAGS: 00010002 torvalds#6 [d72d3cb4] isolate_migratepages at c030b15a torvalds#7 [d72d3d14] zone_watermark_ok at c02d26cb torvalds#8 [d72d3d2c] compact_zone at c030b8d torvalds#9 [d72d3d68] compact_zone_order at c030bba1 torvalds#10 [d72d3db4] try_to_compact_pages at c030bc84 torvalds#11 [d72d3ddc] __alloc_pages_direct_compact at c02d61e7 torvalds#12 [d72d3e08] __alloc_pages_slowpath at c02d66c7 torvalds#13 [d72d3e78] __alloc_pages_nodemask at c02d6a97 torvalds#14 [d72d3eb8] alloc_pages_vma at c030a845 torvalds#15 [d72d3ed4] do_huge_pmd_anonymous_page at c03178eb torvalds#16 [d72d3f00] handle_mm_fault at c02f36c6 torvalds#17 [d72d3f30] do_page_fault at c05c70ed torvalds#18 [d72d3fb] error_code (via page_fault) at c05c47a4 EAX: b71ff000 EBX: 00000001 ECX: 00001600 EDX: 00000431 DS: 007b ESI: 08048950 ES: 007b EDI: bfaa3788 SS: 007b ESP: bfaa36e0 EBP: bfaa3828 GS: 6f50 CS: 0073 EIP: 080487c8 ERR: ffffffff EFLAGS: 00010202 It was also reported by Herbert van den Bergh against 3.1-based kernel with the following snippet from the console log. BUG: unable to handle kernel paging request at 01c00008 IP: [<c0522399>] isolate_migratepages+0x119/0x390 *pdpt = 000000002f7ce001 *pde = 0000000000000000 It is expected that it also affects 3.2.x and current mainline. The problem is that pfn_valid is only called on the first PFN being checked and that PFN is not necessarily aligned. Lets say we have a case like this H = MAX_ORDER_NR_PAGES boundary | = pageblock boundary m = cc->migrate_pfn f = cc->free_pfn o = memory hole H------|------H------|----m-Hoooooo|ooooooH-f----|------H The migrate_pfn is just below a memory hole and the free scanner is beyond the hole. When isolate_migratepages started, it scans from migrate_pfn to migrate_pfn+pageblock_nr_pages which is now in a memory hole. It checks pfn_valid() on the first PFN but then scans into the hole where there are not necessarily valid struct pages. This patch ensures that isolate_migratepages calls pfn_valid when necessary. Reported-by: Herbert van den Bergh <herbert.van.den.bergh@oracle.com> Tested-by: Herbert van den Bergh <herbert.van.den.bergh@oracle.com> Signed-off-by: Mel Gorman <mgorman@suse.de> Acked-by: Michal Nazarewicz <mina86@mina86.com> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

If the netdev is already in NETREG_UNREGISTERING/_UNREGISTERED state, do not update the real num tx queues. netdev_queue_update_kobjects() is already called via remove_queue_kobjects() at NETREG_UNREGISTERING time. So, when upper layer driver, e.g., FCoE protocol stack is monitoring the netdev event of NETDEV_UNREGISTER and calls back to LLD ndo_fcoe_disable() to remove extra queues allocated for FCoE, the associated txq sysfs kobjects are already removed, and trying to update the real num queues would cause something like below: ... PID: 25138 TASK: ffff88021e64c440 CPU: 3 COMMAND: "kworker/3:3" #0 [ffff88021f007760] machine_kexec at ffffffff810226d9 #1 [ffff88021f0077d0] crash_kexec at ffffffff81089d2d #2 [ffff88021f0078a0] oops_end at ffffffff813bca78 #3 [ffff88021f0078d0] no_context at ffffffff81029e72 #4 [ffff88021f007920] __bad_area_nosemaphore at ffffffff8102a155 #5 [ffff88021f0079f0] bad_area_nosemaphore at ffffffff8102a23e torvalds#6 [ffff88021f007a00] do_page_fault at ffffffff813bf32e torvalds#7 [ffff88021f007b10] page_fault at ffffffff813bc045 [exception RIP: sysfs_find_dirent+17] RIP: ffffffff81178611 RSP: ffff88021f007bc0 RFLAGS: 00010246 RAX: ffff88021e64c440 RBX: ffffffff8156cc63 RCX: 0000000000000004 RDX: ffffffff8156cc63 RSI: 0000000000000000 RDI: 0000000000000000 RBP: ffff88021f007be0 R8: 0000000000000004 R9: 0000000000000008 R10: ffffffff816fed00 R11: 0000000000000004 R12: 0000000000000000 R13: ffffffff8156cc63 R14: 0000000000000000 R15: ffff8802222a0000 ORIG_RAX: ffffffffffffffff CS: 0010 SS: 0018 torvalds#8 [ffff88021f007be8] sysfs_get_dirent at ffffffff81178c07 torvalds#9 [ffff88021f007c18] sysfs_remove_group at ffffffff8117ac27 torvalds#10 [ffff88021f007c48] netdev_queue_update_kobjects at ffffffff813178f9 torvalds#11 [ffff88021f007c88] netif_set_real_num_tx_queues at ffffffff81303e38 torvalds#12 [ffff88021f007cc8] ixgbe_set_num_queues at ffffffffa0249763 [ixgbe] torvalds#13 [ffff88021f007cf8] ixgbe_init_interrupt_scheme at ffffffffa024ea89 [ixgbe] torvalds#14 [ffff88021f007d48] ixgbe_fcoe_disable at ffffffffa0267113 [ixgbe] torvalds#15 [ffff88021f007d68] vlan_dev_fcoe_disable at ffffffffa014fef5 [8021q] torvalds#16 [ffff88021f007d78] fcoe_interface_cleanup at ffffffffa02b7dfd [fcoe] torvalds#17 [ffff88021f007df8] fcoe_destroy_work at ffffffffa02b7f08 [fcoe] torvalds#18 [ffff88021f007e18] process_one_work at ffffffff8105d7ca torvalds#19 [ffff88021f007e68] worker_thread at ffffffff81060513 torvalds#20 [ffff88021f007ee8] kthread at ffffffff810648b6 torvalds#21 [ffff88021f007f48] kernel_thread_helper at ffffffff813c40f4 Signed-off-by: Yi Zou <yi.zou@intel.com> Tested-by: Ross Brattain <ross.b.brattain@intel.com> Tested-by: Stephen Ko <stephen.s.ko@intel.com> Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>

…S block during isolation for migration commit 0bf380b upstream. When isolating for migration, migration starts at the start of a zone which is not necessarily pageblock aligned. Further, it stops isolating when COMPACT_CLUSTER_MAX pages are isolated so migrate_pfn is generally not aligned. This allows isolate_migratepages() to call pfn_to_page() on an invalid PFN which can result in a crash. This was originally reported against a 3.0-based kernel with the following trace in a crash dump. PID: 9902 TASK: d47aecd0 CPU: 0 COMMAND: "memcg_process_s" #0 [d72d3ad0] crash_kexec at c028cfdb #1 [d72d3b24] oops_end at c05c5322 #2 [d72d3b38] __bad_area_nosemaphore at c0227e60 #3 [d72d3bec] bad_area at c0227fb6 #4 [d72d3c00] do_page_fault at c05c72e #5 [d72d3c80] error_code (via page_fault) at c05c47a4 EAX: 00000000 EBX: 000c0000 ECX: 00000001 EDX: 00000807 EBP: 000c0000 DS: 007b ESI: 00000001 ES: 007b EDI: f3000a80 GS: 6f50 CS: 0060 EIP: c030b15a ERR: ffffffff EFLAGS: 00010002 torvalds#6 [d72d3cb4] isolate_migratepages at c030b15a torvalds#7 [d72d3d14] zone_watermark_ok at c02d26cb torvalds#8 [d72d3d2c] compact_zone at c030b8d torvalds#9 [d72d3d68] compact_zone_order at c030bba1 torvalds#10 [d72d3db4] try_to_compact_pages at c030bc84 torvalds#11 [d72d3ddc] __alloc_pages_direct_compact at c02d61e7 torvalds#12 [d72d3e08] __alloc_pages_slowpath at c02d66c7 torvalds#13 [d72d3e78] __alloc_pages_nodemask at c02d6a97 torvalds#14 [d72d3eb8] alloc_pages_vma at c030a845 torvalds#15 [d72d3ed4] do_huge_pmd_anonymous_page at c03178eb torvalds#16 [d72d3f00] handle_mm_fault at c02f36c6 torvalds#17 [d72d3f30] do_page_fault at c05c70ed torvalds#18 [d72d3fb] error_code (via page_fault) at c05c47a4 EAX: b71ff000 EBX: 00000001 ECX: 00001600 EDX: 00000431 DS: 007b ESI: 08048950 ES: 007b EDI: bfaa3788 SS: 007b ESP: bfaa36e0 EBP: bfaa3828 GS: 6f50 CS: 0073 EIP: 080487c8 ERR: ffffffff EFLAGS: 00010202 It was also reported by Herbert van den Bergh against 3.1-based kernel with the following snippet from the console log. BUG: unable to handle kernel paging request at 01c00008 IP: [<c0522399>] isolate_migratepages+0x119/0x390 *pdpt = 000000002f7ce001 *pde = 0000000000000000 It is expected that it also affects 3.2.x and current mainline. The problem is that pfn_valid is only called on the first PFN being checked and that PFN is not necessarily aligned. Lets say we have a case like this H = MAX_ORDER_NR_PAGES boundary | = pageblock boundary m = cc->migrate_pfn f = cc->free_pfn o = memory hole H------|------H------|----m-Hoooooo|ooooooH-f----|------H The migrate_pfn is just below a memory hole and the free scanner is beyond the hole. When isolate_migratepages started, it scans from migrate_pfn to migrate_pfn+pageblock_nr_pages which is now in a memory hole. It checks pfn_valid() on the first PFN but then scans into the hole where there are not necessarily valid struct pages. This patch ensures that isolate_migratepages calls pfn_valid when necessary. Reported-by: Herbert van den Bergh <herbert.van.den.bergh@oracle.com> Tested-by: Herbert van den Bergh <herbert.van.den.bergh@oracle.com> Signed-off-by: Mel Gorman <mgorman@suse.de> Acked-by: Michal Nazarewicz <mina86@mina86.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

…S block during isolation for migration commit 0bf380b upstream. When isolating for migration, migration starts at the start of a zone which is not necessarily pageblock aligned. Further, it stops isolating when COMPACT_CLUSTER_MAX pages are isolated so migrate_pfn is generally not aligned. This allows isolate_migratepages() to call pfn_to_page() on an invalid PFN which can result in a crash. This was originally reported against a 3.0-based kernel with the following trace in a crash dump. PID: 9902 TASK: d47aecd0 CPU: 0 COMMAND: "memcg_process_s" #0 [d72d3ad0] crash_kexec at c028cfdb #1 [d72d3b24] oops_end at c05c5322 #2 [d72d3b38] __bad_area_nosemaphore at c0227e60 #3 [d72d3bec] bad_area at c0227fb6 #4 [d72d3c00] do_page_fault at c05c72e #5 [d72d3c80] error_code (via page_fault) at c05c47a4 EAX: 00000000 EBX: 000c0000 ECX: 00000001 EDX: 00000807 EBP: 000c0000 DS: 007b ESI: 00000001 ES: 007b EDI: f3000a80 GS: 6f50 CS: 0060 EIP: c030b15a ERR: ffffffff EFLAGS: 00010002 #6 [d72d3cb4] isolate_migratepages at c030b15a #7 [d72d3d14] zone_watermark_ok at c02d26cb #8 [d72d3d2c] compact_zone at c030b8d #9 [d72d3d68] compact_zone_order at c030bba1 torvalds#10 [d72d3db4] try_to_compact_pages at c030bc84 torvalds#11 [d72d3ddc] __alloc_pages_direct_compact at c02d61e7 torvalds#12 [d72d3e08] __alloc_pages_slowpath at c02d66c7 torvalds#13 [d72d3e78] __alloc_pages_nodemask at c02d6a97 torvalds#14 [d72d3eb8] alloc_pages_vma at c030a845 torvalds#15 [d72d3ed4] do_huge_pmd_anonymous_page at c03178eb torvalds#16 [d72d3f00] handle_mm_fault at c02f36c6 torvalds#17 [d72d3f30] do_page_fault at c05c70ed torvalds#18 [d72d3fb] error_code (via page_fault) at c05c47a4 EAX: b71ff000 EBX: 00000001 ECX: 00001600 EDX: 00000431 DS: 007b ESI: 08048950 ES: 007b EDI: bfaa3788 SS: 007b ESP: bfaa36e0 EBP: bfaa3828 GS: 6f50 CS: 0073 EIP: 080487c8 ERR: ffffffff EFLAGS: 00010202 It was also reported by Herbert van den Bergh against 3.1-based kernel with the following snippet from the console log. BUG: unable to handle kernel paging request at 01c00008 IP: [<c0522399>] isolate_migratepages+0x119/0x390 *pdpt = 000000002f7ce001 *pde = 0000000000000000 It is expected that it also affects 3.2.x and current mainline. The problem is that pfn_valid is only called on the first PFN being checked and that PFN is not necessarily aligned. Lets say we have a case like this H = MAX_ORDER_NR_PAGES boundary | = pageblock boundary m = cc->migrate_pfn f = cc->free_pfn o = memory hole H------|------H------|----m-Hoooooo|ooooooH-f----|------H The migrate_pfn is just below a memory hole and the free scanner is beyond the hole. When isolate_migratepages started, it scans from migrate_pfn to migrate_pfn+pageblock_nr_pages which is now in a memory hole. It checks pfn_valid() on the first PFN but then scans into the hole where there are not necessarily valid struct pages. This patch ensures that isolate_migratepages calls pfn_valid when necessary. Reported-by: Herbert van den Bergh <herbert.van.den.bergh@oracle.com> Tested-by: Herbert van den Bergh <herbert.van.den.bergh@oracle.com> Signed-off-by: Mel Gorman <mgorman@suse.de> Acked-by: Michal Nazarewicz <mina86@mina86.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

…S block during isolation for migration BugLink: http://bugs.launchpad.net/bugs/931719 commit 0bf380b upstream. When isolating for migration, migration starts at the start of a zone which is not necessarily pageblock aligned. Further, it stops isolating when COMPACT_CLUSTER_MAX pages are isolated so migrate_pfn is generally not aligned. This allows isolate_migratepages() to call pfn_to_page() on an invalid PFN which can result in a crash. This was originally reported against a 3.0-based kernel with the following trace in a crash dump. PID: 9902 TASK: d47aecd0 CPU: 0 COMMAND: "memcg_process_s" #0 [d72d3ad0] crash_kexec at c028cfdb #1 [d72d3b24] oops_end at c05c5322 #2 [d72d3b38] __bad_area_nosemaphore at c0227e60 #3 [d72d3bec] bad_area at c0227fb6 #4 [d72d3c00] do_page_fault at c05c72e #5 [d72d3c80] error_code (via page_fault) at c05c47a4 EAX: 00000000 EBX: 000c0000 ECX: 00000001 EDX: 00000807 EBP: 000c0000 DS: 007b ESI: 00000001 ES: 007b EDI: f3000a80 GS: 6f50 CS: 0060 EIP: c030b15a ERR: ffffffff EFLAGS: 00010002 torvalds#6 [d72d3cb4] isolate_migratepages at c030b15a torvalds#7 [d72d3d14] zone_watermark_ok at c02d26cb torvalds#8 [d72d3d2c] compact_zone at c030b8d torvalds#9 [d72d3d68] compact_zone_order at c030bba1 torvalds#10 [d72d3db4] try_to_compact_pages at c030bc84 torvalds#11 [d72d3ddc] __alloc_pages_direct_compact at c02d61e7 torvalds#12 [d72d3e08] __alloc_pages_slowpath at c02d66c7 torvalds#13 [d72d3e78] __alloc_pages_nodemask at c02d6a97 torvalds#14 [d72d3eb8] alloc_pages_vma at c030a845 torvalds#15 [d72d3ed4] do_huge_pmd_anonymous_page at c03178eb torvalds#16 [d72d3f00] handle_mm_fault at c02f36c6 torvalds#17 [d72d3f30] do_page_fault at c05c70ed torvalds#18 [d72d3fb] error_code (via page_fault) at c05c47a4 EAX: b71ff000 EBX: 00000001 ECX: 00001600 EDX: 00000431 DS: 007b ESI: 08048950 ES: 007b EDI: bfaa3788 SS: 007b ESP: bfaa36e0 EBP: bfaa3828 GS: 6f50 CS: 0073 EIP: 080487c8 ERR: ffffffff EFLAGS: 00010202 It was also reported by Herbert van den Bergh against 3.1-based kernel with the following snippet from the console log. BUG: unable to handle kernel paging request at 01c00008 IP: [<c0522399>] isolate_migratepages+0x119/0x390 *pdpt = 000000002f7ce001 *pde = 0000000000000000 It is expected that it also affects 3.2.x and current mainline. The problem is that pfn_valid is only called on the first PFN being checked and that PFN is not necessarily aligned. Lets say we have a case like this H = MAX_ORDER_NR_PAGES boundary | = pageblock boundary m = cc->migrate_pfn f = cc->free_pfn o = memory hole H------|------H------|----m-Hoooooo|ooooooH-f----|------H The migrate_pfn is just below a memory hole and the free scanner is beyond the hole. When isolate_migratepages started, it scans from migrate_pfn to migrate_pfn+pageblock_nr_pages which is now in a memory hole. It checks pfn_valid() on the first PFN but then scans into the hole where there are not necessarily valid struct pages. This patch ensures that isolate_migratepages calls pfn_valid when necessary. Reported-by: Herbert van den Bergh <herbert.van.den.bergh@oracle.com> Tested-by: Herbert van den Bergh <herbert.van.den.bergh@oracle.com> Signed-off-by: Mel Gorman <mgorman@suse.de> Acked-by: Michal Nazarewicz <mina86@mina86.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Tim Gardner <tim.gardner@canonical.com>

…S block during isolation for migration commit 0bf380b upstream. When isolating for migration, migration starts at the start of a zone which is not necessarily pageblock aligned. Further, it stops isolating when COMPACT_CLUSTER_MAX pages are isolated so migrate_pfn is generally not aligned. This allows isolate_migratepages() to call pfn_to_page() on an invalid PFN which can result in a crash. This was originally reported against a 3.0-based kernel with the following trace in a crash dump. PID: 9902 TASK: d47aecd0 CPU: 0 COMMAND: "memcg_process_s" #0 [d72d3ad0] crash_kexec at c028cfdb #1 [d72d3b24] oops_end at c05c5322 #2 [d72d3b38] __bad_area_nosemaphore at c0227e60 #3 [d72d3bec] bad_area at c0227fb6 #4 [d72d3c00] do_page_fault at c05c72e #5 [d72d3c80] error_code (via page_fault) at c05c47a4 EAX: 00000000 EBX: 000c0000 ECX: 00000001 EDX: 00000807 EBP: 000c0000 DS: 007b ESI: 00000001 ES: 007b EDI: f3000a80 GS: 6f50 CS: 0060 EIP: c030b15a ERR: ffffffff EFLAGS: 00010002 #6 [d72d3cb4] isolate_migratepages at c030b15a #7 [d72d3d14] zone_watermark_ok at c02d26cb #8 [d72d3d2c] compact_zone at c030b8d #9 [d72d3d68] compact_zone_order at c030bba1 torvalds#10 [d72d3db4] try_to_compact_pages at c030bc84 torvalds#11 [d72d3ddc] __alloc_pages_direct_compact at c02d61e7 torvalds#12 [d72d3e08] __alloc_pages_slowpath at c02d66c7 torvalds#13 [d72d3e78] __alloc_pages_nodemask at c02d6a97 torvalds#14 [d72d3eb8] alloc_pages_vma at c030a845 torvalds#15 [d72d3ed4] do_huge_pmd_anonymous_page at c03178eb torvalds#16 [d72d3f00] handle_mm_fault at c02f36c6 torvalds#17 [d72d3f30] do_page_fault at c05c70ed torvalds#18 [d72d3fb] error_code (via page_fault) at c05c47a4 EAX: b71ff000 EBX: 00000001 ECX: 00001600 EDX: 00000431 DS: 007b ESI: 08048950 ES: 007b EDI: bfaa3788 SS: 007b ESP: bfaa36e0 EBP: bfaa3828 GS: 6f50 CS: 0073 EIP: 080487c8 ERR: ffffffff EFLAGS: 00010202 It was also reported by Herbert van den Bergh against 3.1-based kernel with the following snippet from the console log. BUG: unable to handle kernel paging request at 01c00008 IP: [<c0522399>] isolate_migratepages+0x119/0x390 *pdpt = 000000002f7ce001 *pde = 0000000000000000 It is expected that it also affects 3.2.x and current mainline. The problem is that pfn_valid is only called on the first PFN being checked and that PFN is not necessarily aligned. Lets say we have a case like this H = MAX_ORDER_NR_PAGES boundary | = pageblock boundary m = cc->migrate_pfn f = cc->free_pfn o = memory hole H------|------H------|----m-Hoooooo|ooooooH-f----|------H The migrate_pfn is just below a memory hole and the free scanner is beyond the hole. When isolate_migratepages started, it scans from migrate_pfn to migrate_pfn+pageblock_nr_pages which is now in a memory hole. It checks pfn_valid() on the first PFN but then scans into the hole where there are not necessarily valid struct pages. This patch ensures that isolate_migratepages calls pfn_valid when necessary. Reported-by: Herbert van den Bergh <herbert.van.den.bergh@oracle.com> Tested-by: Herbert van den Bergh <herbert.van.den.bergh@oracle.com> Signed-off-by: Mel Gorman <mgorman@suse.de> Acked-by: Michal Nazarewicz <mina86@mina86.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

…S block during isolation for migration commit 0bf380b upstream. When isolating for migration, migration starts at the start of a zone which is not necessarily pageblock aligned. Further, it stops isolating when COMPACT_CLUSTER_MAX pages are isolated so migrate_pfn is generally not aligned. This allows isolate_migratepages() to call pfn_to_page() on an invalid PFN which can result in a crash. This was originally reported against a 3.0-based kernel with the following trace in a crash dump. PID: 9902 TASK: d47aecd0 CPU: 0 COMMAND: "memcg_process_s" #0 [d72d3ad0] crash_kexec at c028cfdb #1 [d72d3b24] oops_end at c05c5322 #2 [d72d3b38] __bad_area_nosemaphore at c0227e60 #3 [d72d3bec] bad_area at c0227fb6 #4 [d72d3c00] do_page_fault at c05c72e #5 [d72d3c80] error_code (via page_fault) at c05c47a4 EAX: 00000000 EBX: 000c0000 ECX: 00000001 EDX: 00000807 EBP: 000c0000 DS: 007b ESI: 00000001 ES: 007b EDI: f3000a80 GS: 6f50 CS: 0060 EIP: c030b15a ERR: ffffffff EFLAGS: 00010002 #6 [d72d3cb4] isolate_migratepages at c030b15a #7 [d72d3d14] zone_watermark_ok at c02d26cb #8 [d72d3d2c] compact_zone at c030b8d #9 [d72d3d68] compact_zone_order at c030bba1 #10 [d72d3db4] try_to_compact_pages at c030bc84 #11 [d72d3ddc] __alloc_pages_direct_compact at c02d61e7 #12 [d72d3e08] __alloc_pages_slowpath at c02d66c7 #13 [d72d3e78] __alloc_pages_nodemask at c02d6a97 #14 [d72d3eb8] alloc_pages_vma at c030a845 #15 [d72d3ed4] do_huge_pmd_anonymous_page at c03178eb #16 [d72d3f00] handle_mm_fault at c02f36c6 #17 [d72d3f30] do_page_fault at c05c70ed #18 [d72d3fb] error_code (via page_fault) at c05c47a4 EAX: b71ff000 EBX: 00000001 ECX: 00001600 EDX: 00000431 DS: 007b ESI: 08048950 ES: 007b EDI: bfaa3788 SS: 007b ESP: bfaa36e0 EBP: bfaa3828 GS: 6f50 CS: 0073 EIP: 080487c8 ERR: ffffffff EFLAGS: 00010202 It was also reported by Herbert van den Bergh against 3.1-based kernel with the following snippet from the console log. BUG: unable to handle kernel paging request at 01c00008 IP: [<c0522399>] isolate_migratepages+0x119/0x390 *pdpt = 000000002f7ce001 *pde = 0000000000000000 It is expected that it also affects 3.2.x and current mainline. The problem is that pfn_valid is only called on the first PFN being checked and that PFN is not necessarily aligned. Lets say we have a case like this H = MAX_ORDER_NR_PAGES boundary | = pageblock boundary m = cc->migrate_pfn f = cc->free_pfn o = memory hole H------|------H------|----m-Hoooooo|ooooooH-f----|------H The migrate_pfn is just below a memory hole and the free scanner is beyond the hole. When isolate_migratepages started, it scans from migrate_pfn to migrate_pfn+pageblock_nr_pages which is now in a memory hole. It checks pfn_valid() on the first PFN but then scans into the hole where there are not necessarily valid struct pages. This patch ensures that isolate_migratepages calls pfn_valid when necessary. Reported-by: Herbert van den Bergh <herbert.van.den.bergh@oracle.com> Tested-by: Herbert van den Bergh <herbert.van.den.bergh@oracle.com> Signed-off-by: Mel Gorman <mgorman@suse.de> Acked-by: Michal Nazarewicz <mina86@mina86.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

…S block during isolation for migration commit 0bf380b upstream. When isolating for migration, migration starts at the start of a zone which is not necessarily pageblock aligned. Further, it stops isolating when COMPACT_CLUSTER_MAX pages are isolated so migrate_pfn is generally not aligned. This allows isolate_migratepages() to call pfn_to_page() on an invalid PFN which can result in a crash. This was originally reported against a 3.0-based kernel with the following trace in a crash dump. PID: 9902 TASK: d47aecd0 CPU: 0 COMMAND: "memcg_process_s" #0 [d72d3ad0] crash_kexec at c028cfdb #1 [d72d3b24] oops_end at c05c5322 #2 [d72d3b38] __bad_area_nosemaphore at c0227e60 #3 [d72d3bec] bad_area at c0227fb6 #4 [d72d3c00] do_page_fault at c05c72e #5 [d72d3c80] error_code (via page_fault) at c05c47a4 EAX: 00000000 EBX: 000c0000 ECX: 00000001 EDX: 00000807 EBP: 000c0000 DS: 007b ESI: 00000001 ES: 007b EDI: f3000a80 GS: 6f50 CS: 0060 EIP: c030b15a ERR: ffffffff EFLAGS: 00010002 #6 [d72d3cb4] isolate_migratepages at c030b15a #7 [d72d3d14] zone_watermark_ok at c02d26cb #8 [d72d3d2c] compact_zone at c030b8d #9 [d72d3d68] compact_zone_order at c030bba1 torvalds#10 [d72d3db4] try_to_compact_pages at c030bc84 torvalds#11 [d72d3ddc] __alloc_pages_direct_compact at c02d61e7 torvalds#12 [d72d3e08] __alloc_pages_slowpath at c02d66c7 torvalds#13 [d72d3e78] __alloc_pages_nodemask at c02d6a97 torvalds#14 [d72d3eb8] alloc_pages_vma at c030a845 torvalds#15 [d72d3ed4] do_huge_pmd_anonymous_page at c03178eb torvalds#16 [d72d3f00] handle_mm_fault at c02f36c6 torvalds#17 [d72d3f30] do_page_fault at c05c70ed torvalds#18 [d72d3fb] error_code (via page_fault) at c05c47a4 EAX: b71ff000 EBX: 00000001 ECX: 00001600 EDX: 00000431 DS: 007b ESI: 08048950 ES: 007b EDI: bfaa3788 SS: 007b ESP: bfaa36e0 EBP: bfaa3828 GS: 6f50 CS: 0073 EIP: 080487c8 ERR: ffffffff EFLAGS: 00010202 It was also reported by Herbert van den Bergh against 3.1-based kernel with the following snippet from the console log. BUG: unable to handle kernel paging request at 01c00008 IP: [<c0522399>] isolate_migratepages+0x119/0x390 *pdpt = 000000002f7ce001 *pde = 0000000000000000 It is expected that it also affects 3.2.x and current mainline. The problem is that pfn_valid is only called on the first PFN being checked and that PFN is not necessarily aligned. Lets say we have a case like this H = MAX_ORDER_NR_PAGES boundary | = pageblock boundary m = cc->migrate_pfn f = cc->free_pfn o = memory hole H------|------H------|----m-Hoooooo|ooooooH-f----|------H The migrate_pfn is just below a memory hole and the free scanner is beyond the hole. When isolate_migratepages started, it scans from migrate_pfn to migrate_pfn+pageblock_nr_pages which is now in a memory hole. It checks pfn_valid() on the first PFN but then scans into the hole where there are not necessarily valid struct pages. This patch ensures that isolate_migratepages calls pfn_valid when necessary. Reported-by: Herbert van den Bergh <herbert.van.den.bergh@oracle.com> Tested-by: Herbert van den Bergh <herbert.van.den.bergh@oracle.com> Signed-off-by: Mel Gorman <mgorman@suse.de> Acked-by: Michal Nazarewicz <mina86@mina86.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

ismaell · 2012-05-30T07:31:26Z

Nonsense. Markdown is for wikis, not for help files.

ghost · 2012-05-30T12:04:44Z

It's also for READMEs.

[ Upstream commit 14e4e41 ] A false-positive kmsan report is detected when running ping command. An inline assembly instruction 'vstl' can write varied amount of bytes depending on value of 'index' argument. If 'index' > 0, 'vstl' writes at least 2 bytes. clang generates kmsan write helper call depending on inline assembly constraints. Constraints are evaluated compile-time, but value of 'index' argument is known only at runtime. clang currently generates call to __msan_instrument_asm_store with 1 byte as size. Manually call kmsan function to indicate correct amount of bytes written and fix false-positive report. This change fixes following kmsan reports: [ 36.563119] ===================================================== [ 36.563594] BUG: KMSAN: uninit-value in virtqueue_add+0x35c6/0x7c70 [ 36.563852] virtqueue_add+0x35c6/0x7c70 [ 36.564016] virtqueue_add_outbuf+0xa0/0xb0 [ 36.564266] start_xmit+0x288c/0x4a20 [ 36.564460] dev_hard_start_xmit+0x302/0x900 [ 36.564649] sch_direct_xmit+0x340/0xea0 [ 36.564894] __dev_queue_xmit+0x2e94/0x59b0 [ 36.565058] neigh_resolve_output+0x936/0xb40 [ 36.565278] __neigh_update+0x2f66/0x3a60 [ 36.565499] neigh_update+0x52/0x60 [ 36.565683] arp_process+0x1588/0x2de0 [ 36.565916] NF_HOOK+0x1da/0x240 [ 36.566087] arp_rcv+0x3e4/0x6e0 [ 36.566306] __netif_receive_skb_list_core+0x1374/0x15a0 [ 36.566527] netif_receive_skb_list_internal+0x1116/0x17d0 [ 36.566710] napi_complete_done+0x376/0x740 [ 36.566918] virtnet_poll+0x1bae/0x2910 [ 36.567130] __napi_poll+0xf4/0x830 [ 36.567294] net_rx_action+0x97c/0x1ed0 [ 36.567556] handle_softirqs+0x306/0xe10 [ 36.567731] irq_exit_rcu+0x14c/0x2e0 [ 36.567910] do_io_irq+0xd4/0x120 [ 36.568139] io_int_handler+0xc2/0xe8 [ 36.568299] arch_cpu_idle+0xb0/0xc0 [ 36.568540] arch_cpu_idle+0x76/0xc0 [ 36.568726] default_idle_call+0x40/0x70 [ 36.568953] do_idle+0x1d6/0x390 [ 36.569486] cpu_startup_entry+0x9a/0xb0 [ 36.569745] rest_init+0x1ea/0x290 [ 36.570029] start_kernel+0x95e/0xb90 [ 36.570348] startup_continue+0x2e/0x40 [ 36.570703] [ 36.570798] Uninit was created at: [ 36.571002] kmem_cache_alloc_node_noprof+0x9e8/0x10e0 [ 36.571261] kmalloc_reserve+0x12a/0x470 [ 36.571553] __alloc_skb+0x310/0x860 [ 36.571844] __ip_append_data+0x483e/0x6a30 [ 36.572170] ip_append_data+0x11c/0x1e0 [ 36.572477] raw_sendmsg+0x1c8c/0x2180 [ 36.572818] inet_sendmsg+0xe6/0x190 [ 36.573142] __sys_sendto+0x55e/0x8e0 [ 36.573392] __s390x_sys_socketcall+0x19ae/0x2ba0 [ 36.573571] __do_syscall+0x12e/0x240 [ 36.573823] system_call+0x6e/0x90 [ 36.573976] [ 36.574017] Byte 35 of 98 is uninitialized [ 36.574082] Memory access of size 98 starts at 0000000007aa0012 [ 36.574218] [ 36.574325] CPU: 0 UID: 0 PID: 0 Comm: swapper/0 Tainted: G B N 6.17.0-dirty torvalds#16 NONE [ 36.574541] Tainted: [B]=BAD_PAGE, [N]=TEST [ 36.574617] Hardware name: IBM 3931 A01 703 (KVM/Linux) [ 36.574755] ===================================================== [ 63.532541] ===================================================== [ 63.533639] BUG: KMSAN: uninit-value in virtqueue_add+0x35c6/0x7c70 [ 63.533989] virtqueue_add+0x35c6/0x7c70 [ 63.534940] virtqueue_add_outbuf+0xa0/0xb0 [ 63.535861] start_xmit+0x288c/0x4a20 [ 63.536708] dev_hard_start_xmit+0x302/0x900 [ 63.537020] sch_direct_xmit+0x340/0xea0 [ 63.537997] __dev_queue_xmit+0x2e94/0x59b0 [ 63.538819] neigh_resolve_output+0x936/0xb40 [ 63.539793] ip_finish_output2+0x1ee2/0x2200 [ 63.540784] __ip_finish_output+0x272/0x7a0 [ 63.541765] ip_finish_output+0x4e/0x5e0 [ 63.542791] ip_output+0x166/0x410 [ 63.543771] ip_push_pending_frames+0x1a2/0x470 [ 63.544753] raw_sendmsg+0x1f06/0x2180 [ 63.545033] inet_sendmsg+0xe6/0x190 [ 63.546006] __sys_sendto+0x55e/0x8e0 [ 63.546859] __s390x_sys_socketcall+0x19ae/0x2ba0 [ 63.547730] __do_syscall+0x12e/0x240 [ 63.548019] system_call+0x6e/0x90 [ 63.548989] [ 63.549779] Uninit was created at: [ 63.550691] kmem_cache_alloc_node_noprof+0x9e8/0x10e0 [ 63.550975] kmalloc_reserve+0x12a/0x470 [ 63.551969] __alloc_skb+0x310/0x860 [ 63.552949] __ip_append_data+0x483e/0x6a30 [ 63.553902] ip_append_data+0x11c/0x1e0 [ 63.554912] raw_sendmsg+0x1c8c/0x2180 [ 63.556719] inet_sendmsg+0xe6/0x190 [ 63.557534] __sys_sendto+0x55e/0x8e0 [ 63.557875] __s390x_sys_socketcall+0x19ae/0x2ba0 [ 63.558869] __do_syscall+0x12e/0x240 [ 63.559832] system_call+0x6e/0x90 [ 63.560780] [ 63.560972] Byte 35 of 98 is uninitialized [ 63.561741] Memory access of size 98 starts at 0000000005704312 [ 63.561950] [ 63.562824] CPU: 3 UID: 0 PID: 192 Comm: ping Tainted: G B N 6.17.0-dirty torvalds#16 NONE [ 63.563868] Tainted: [B]=BAD_PAGE, [N]=TEST [ 63.564751] Hardware name: IBM 3931 A01 703 (KVM/Linux) [ 63.564986] ===================================================== Fixes: dcd3e1d ("s390/checksum: provide csum_partial_copy_nocheck()") Signed-off-by: Aleksei Nikiforov <aleksei.nikiforov@linux.ibm.com> Signed-off-by: Heiko Carstens <hca@linux.ibm.com> Signed-off-by: Sasha Levin <sashal@kernel.org>

The cpuidle governor callbacks for update, select and reflect are always running on the actual idle entering/exiting CPU, so use the more optimized this_cpu_ptr() to access the internal teo data. This brings down the latency-critical teo_reflect() from static void teo_reflect(struct cpuidle_device *dev, int state) { ffffffc080ffcff0: hint #0x19 ffffffc080ffcff4: stp x29, x30, [sp, #-48]! struct teo_cpu *cpu_data = per_cpu_ptr(&teo_cpus, dev->cpu); ffffffc080ffcff8: adrp x2, ffffffc0848c0000 <gicv5_global_data+0x28> { ffffffc080ffcffc: add x29, sp, #0x0 ffffffc080ffd000: stp x19, x20, [sp, torvalds#16] ffffffc080ffd004: orr x20, xzr, x0 struct teo_cpu *cpu_data = per_cpu_ptr(&teo_cpus, dev->cpu); ffffffc080ffd008: add x0, x2, #0xc20 { ffffffc080ffd00c: stp x21, x22, [sp, torvalds#32] struct teo_cpu *cpu_data = per_cpu_ptr(&teo_cpus, dev->cpu); ffffffc080ffd010: adrp x19, ffffffc083eb5000 <cpu_devices+0x78> ffffffc080ffd014: add x19, x19, #0xbb0 ffffffc080ffd018: ldr w3, [x20, #4] dev->last_state_idx = state; to static void teo_reflect(struct cpuidle_device *dev, int state) { ffffffc080ffd034: hint #0x19 ffffffc080ffd038: stp x29, x30, [sp, #-48]! ffffffc080ffd03c: add x29, sp, #0x0 ffffffc080ffd040: stp x19, x20, [sp, torvalds#16] ffffffc080ffd044: orr x20, xzr, x0 struct teo_cpu *cpu_data = this_cpu_ptr(&teo_cpus); ffffffc080ffd048: adrp x19, ffffffc083eb5000 <cpu_devices+0x78> { ffffffc080ffd04c: stp x21, x22, [sp, torvalds#32] struct teo_cpu *cpu_data = this_cpu_ptr(&teo_cpus); ffffffc080ffd050: add x19, x19, #0xbb0 dev->last_state_idx = state; This saves us: adrp x2, ffffffc0848c0000 <gicv5_global_data+0x28> add x0, x2, #0xc20 ldr w3, [x20, #4] Signed-off-by: Christian Loehle <christian.loehle@arm.com> [ rjw: Subject tweak ] Link: https://patch.msgid.link/20251110120819.714560-1-christian.loehle@arm.com Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

Do not use memcpy() to extract syscall arguments from struct pt_regs but rather just perform direct assignments. Update syscall_set_arguments() too to keep syscall_get_arguments() and syscall_set_arguments() in sync. With Generic Entry patch[1] and turn on audit, the performance benchmarks from perf bench basic syscall on kunpeng920 gives roughly a 1% performance uplift. | Metric | W/O this patch | With this patch | Change | | ---------- | -------------- | --------------- | --------- | | Total time | 2.241 [sec] | 2.211 [sec] | ↓1.36% | | usecs/op | 0.224157 | 0.221146 | ↓1.36% | | ops/sec | 4,461,157 | 4,501,409 | ↑0.9% | Disassembly shows that using direct assignment causes syscall_set_arguments() to be inlined and cuts the instruction count by five or six compared to memcpy(). Because __audit_syscall_entry() only uses four syscall arguments, the compiler has also elided the copy of regs->regs[4] and regs->regs[5]. Before: <syscall_get_arguments.constprop.0>: aa0103e2 mov x2, x1 91002003 add x3, x0, #0x8 f9408804 ldr x4, [x0, torvalds#272] f8008444 str x4, [x2], torvalds#8 a9409404 ldp x4, x5, [x0, torvalds#8] a9009424 stp x4, x5, [x1, torvalds#8] a9418400 ldp x0, x1, [x0, torvalds#24] a9010440 stp x0, x1, [x2, torvalds#16] f9401060 ldr x0, [x3, torvalds#32] f9001040 str x0, [x2, torvalds#32] d65f03c0 ret d503201f nop After: a9408e82 ldp x2, x3, [x20, torvalds#8] 2a1603e0 mov w0, w22 f9400e84 ldr x4, [x20, torvalds#24] f9408a81 ldr x1, [x20, torvalds#272] 9401c4ba bl ffff800080215ca8 <__audit_syscall_entry> This also aligns the implementation with x86 and RISC-V. Link: https://lkml.kernel.org/r/20251201120633.1193122-3-ruanjinjie@huawei.com Link: https://lore.kernel.org/all/20251126071446.3234218-1-ruanjinjie@huawei.com/ [1] Signed-off-by: Jinjie Ruan <ruanjinjie@huawei.com> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Charlie Jenkins <charlie@rivosinc.com> Cc: Christian Zankel <chris@zankel.net> Cc: "Dmitry V. Levin" <ldv@strace.io> Cc: Helge Deller <deller@gmx.de> Cc: Maciej W. Rozycki <macro@orcam.me.uk> Cc: Marc Rutland <mark.rutland@arm.com> Cc: Max Filippov <jcmvbkbc@gmail.com> Cc: Russell King (Oracle) <rmk+kernel@armlinux.org.uk> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Thomas Gleinxer <tglx@linutronix.de> Cc: Will Deacon <will@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

This relocates register pokes of the HDMI VPU encoder out of the HDMI phy driver. As far as HDMI is concerned, the sequence in which the setup is done remains mostly the same. This was tested with modetest, cycling through the following resolutions: #0 3840x2160 60.00 #1 3840x2160 59.94 #2 3840x2160 50.00 #3 3840x2160 30.00 #4 3840x2160 29.97 #5 3840x2160 25.00 torvalds#6 3840x2160 24.00 torvalds#7 3840x2160 23.98 torvalds#8 1920x1080 60.00 torvalds#9 1920x1080 60.00 torvalds#10 1920x1080 59.94 torvalds#11 1920x1080i 30.00 torvalds#12 1920x1080i 29.97 torvalds#13 1920x1080 50.00 torvalds#14 1920x1080i 25.00 torvalds#15 1920x1080 30.00 torvalds#16 1920x1080 29.97 torvalds#17 1920x1080 25.00 torvalds#18 1920x1080 24.00 torvalds#19 1920x1080 23.98 torvalds#20 1280x1024 60.02 torvalds#21 1152x864 59.97 torvalds#22 1280x720 60.00 torvalds#23 1280x720 59.94 torvalds#24 1280x720 50.00 torvalds#25 1024x768 60.00 torvalds#26 800x600 60.32 torvalds#27 720x576 50.00 torvalds#28 720x480 59.94 No regression to report. This is part of an effort to clean up Amlogic HDMI related drivers which should eventually allow to stop using the component API and HHI syscon. Signed-off-by: Jerome Brunet <jbrunet@baylibre.com>

Do not use memcpy() to extract syscall arguments from struct pt_regs but rather just perform direct assignments. Update syscall_set_arguments() too to keep syscall_get_arguments() and syscall_set_arguments() in sync. With Generic Entry patch[1] and turn on audit, the performance benchmarks from perf bench basic syscall on kunpeng920 gives roughly a 1% performance uplift. | Metric | W/O this patch | With this patch | Change | | ---------- | -------------- | --------------- | --------- | | Total time | 2.241 [sec] | 2.211 [sec] | ↓1.36% | | usecs/op | 0.224157 | 0.221146 | ↓1.36% | | ops/sec | 4,461,157 | 4,501,409 | ↑0.9% | Disassembly shows that using direct assignment causes syscall_set_arguments() to be inlined and cuts the instruction count by five or six compared to memcpy(). Because __audit_syscall_entry() only uses four syscall arguments, the compiler has also elided the copy of regs->regs[4] and regs->regs[5]. Before: <syscall_get_arguments.constprop.0>: aa0103e2 mov x2, x1 91002003 add x3, x0, #0x8 f9408804 ldr x4, [x0, torvalds#272] f8008444 str x4, [x2], torvalds#8 a9409404 ldp x4, x5, [x0, torvalds#8] a9009424 stp x4, x5, [x1, torvalds#8] a9418400 ldp x0, x1, [x0, torvalds#24] a9010440 stp x0, x1, [x2, torvalds#16] f9401060 ldr x0, [x3, torvalds#32] f9001040 str x0, [x2, torvalds#32] d65f03c0 ret d503201f nop After: a9408e82 ldp x2, x3, [x20, torvalds#8] 2a1603e0 mov w0, w22 f9400e84 ldr x4, [x20, torvalds#24] f9408a81 ldr x1, [x20, torvalds#272] 9401c4ba bl ffff800080215ca8 <__audit_syscall_entry> This also aligns the implementation with x86 and RISC-V. Link: https://lkml.kernel.org/r/20251201120633.1193122-3-ruanjinjie@huawei.com Link: https://lore.kernel.org/all/20251126071446.3234218-1-ruanjinjie@huawei.com/ [1] Signed-off-by: Jinjie Ruan <ruanjinjie@huawei.com> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Charlie Jenkins <charlie@rivosinc.com> Cc: Christian Zankel <chris@zankel.net> Cc: "Dmitry V. Levin" <ldv@strace.io> Cc: Helge Deller <deller@gmx.de> Cc: Maciej W. Rozycki <macro@orcam.me.uk> Cc: Marc Rutland <mark.rutland@arm.com> Cc: Max Filippov <jcmvbkbc@gmail.com> Cc: Russell King (Oracle) <rmk+kernel@armlinux.org.uk> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Thomas Gleinxer <tglx@linutronix.de> Cc: Will Deacon <will@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

The cpuidle governor callbacks for update, select and reflect are always running on the actual idle entering/exiting CPU, so use the more optimized this_cpu_ptr() to access the internal teo data. This brings down the latency-critical teo_reflect() from static void teo_reflect(struct cpuidle_device *dev, int state) { ffffffc080ffcff0: hint #0x19 ffffffc080ffcff4: stp x29, x30, [sp, #-48]! struct teo_cpu *cpu_data = per_cpu_ptr(&teo_cpus, dev->cpu); ffffffc080ffcff8: adrp x2, ffffffc0848c0000 <gicv5_global_data+0x28> { ffffffc080ffcffc: add x29, sp, #0x0 ffffffc080ffd000: stp x19, x20, [sp, torvalds#16] ffffffc080ffd004: orr x20, xzr, x0 struct teo_cpu *cpu_data = per_cpu_ptr(&teo_cpus, dev->cpu); ffffffc080ffd008: add x0, x2, #0xc20 { ffffffc080ffd00c: stp x21, x22, [sp, torvalds#32] struct teo_cpu *cpu_data = per_cpu_ptr(&teo_cpus, dev->cpu); ffffffc080ffd010: adrp x19, ffffffc083eb5000 <cpu_devices+0x78> ffffffc080ffd014: add x19, x19, #0xbb0 ffffffc080ffd018: ldr w3, [x20, #4] dev->last_state_idx = state; to static void teo_reflect(struct cpuidle_device *dev, int state) { ffffffc080ffd034: hint #0x19 ffffffc080ffd038: stp x29, x30, [sp, #-48]! ffffffc080ffd03c: add x29, sp, #0x0 ffffffc080ffd040: stp x19, x20, [sp, torvalds#16] ffffffc080ffd044: orr x20, xzr, x0 struct teo_cpu *cpu_data = this_cpu_ptr(&teo_cpus); ffffffc080ffd048: adrp x19, ffffffc083eb5000 <cpu_devices+0x78> { ffffffc080ffd04c: stp x21, x22, [sp, torvalds#32] struct teo_cpu *cpu_data = this_cpu_ptr(&teo_cpus); ffffffc080ffd050: add x19, x19, #0xbb0 dev->last_state_idx = state; This saves us: adrp x2, ffffffc0848c0000 <gicv5_global_data+0x28> add x0, x2, #0xc20 ldr w3, [x20, #4] Signed-off-by: Christian Loehle <christian.loehle@arm.com> [ rjw: Subject tweak ] Link: https://patch.msgid.link/20251110120819.714560-1-christian.loehle@arm.com Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

Do not use memcpy() to extract syscall arguments from struct pt_regs but rather just perform direct assignments. Update syscall_set_arguments() too to keep syscall_get_arguments() and syscall_set_arguments() in sync. With Generic Entry patch[1] and turn on audit, the performance benchmarks from perf bench basic syscall on kunpeng920 gives roughly a 1% performance uplift. | Metric | W/O this patch | With this patch | Change | | ---------- | -------------- | --------------- | --------- | | Total time | 2.241 [sec] | 2.211 [sec] | ↓1.36% | | usecs/op | 0.224157 | 0.221146 | ↓1.36% | | ops/sec | 4,461,157 | 4,501,409 | ↑0.9% | Disassembly shows that using direct assignment causes syscall_set_arguments() to be inlined and cuts the instruction count by five or six compared to memcpy(). Because __audit_syscall_entry() only uses four syscall arguments, the compiler has also elided the copy of regs->regs[4] and regs->regs[5]. Before: <syscall_get_arguments.constprop.0>: aa0103e2 mov x2, x1 91002003 add x3, x0, #0x8 f9408804 ldr x4, [x0, torvalds#272] f8008444 str x4, [x2], torvalds#8 a9409404 ldp x4, x5, [x0, torvalds#8] a9009424 stp x4, x5, [x1, torvalds#8] a9418400 ldp x0, x1, [x0, torvalds#24] a9010440 stp x0, x1, [x2, torvalds#16] f9401060 ldr x0, [x3, torvalds#32] f9001040 str x0, [x2, torvalds#32] d65f03c0 ret d503201f nop After: a9408e82 ldp x2, x3, [x20, torvalds#8] 2a1603e0 mov w0, w22 f9400e84 ldr x4, [x20, torvalds#24] f9408a81 ldr x1, [x20, torvalds#272] 9401c4ba bl ffff800080215ca8 <__audit_syscall_entry> This also aligns the implementation with x86 and RISC-V. Link: https://lkml.kernel.org/r/20251201120633.1193122-3-ruanjinjie@huawei.com Link: https://lore.kernel.org/all/20251126071446.3234218-1-ruanjinjie@huawei.com/ [1] Signed-off-by: Jinjie Ruan <ruanjinjie@huawei.com> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Charlie Jenkins <charlie@rivosinc.com> Cc: Christian Zankel <chris@zankel.net> Cc: "Dmitry V. Levin" <ldv@strace.io> Cc: Helge Deller <deller@gmx.de> Cc: Maciej W. Rozycki <macro@orcam.me.uk> Cc: Marc Rutland <mark.rutland@arm.com> Cc: Max Filippov <jcmvbkbc@gmail.com> Cc: Russell King (Oracle) <rmk+kernel@armlinux.org.uk> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Thomas Gleinxer <tglx@linutronix.de> Cc: Will Deacon <will@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

The cpuidle governor callbacks for update, select and reflect are always running on the actual idle entering/exiting CPU, so use the more optimized this_cpu_ptr() to access the internal teo data. This brings down the latency-critical teo_reflect() from static void teo_reflect(struct cpuidle_device *dev, int state) { ffffffc080ffcff0: hint #0x19 ffffffc080ffcff4: stp x29, x30, [sp, #-48]! struct teo_cpu *cpu_data = per_cpu_ptr(&teo_cpus, dev->cpu); ffffffc080ffcff8: adrp x2, ffffffc0848c0000 <gicv5_global_data+0x28> { ffffffc080ffcffc: add x29, sp, #0x0 ffffffc080ffd000: stp x19, x20, [sp, torvalds#16] ffffffc080ffd004: orr x20, xzr, x0 struct teo_cpu *cpu_data = per_cpu_ptr(&teo_cpus, dev->cpu); ffffffc080ffd008: add x0, x2, #0xc20 { ffffffc080ffd00c: stp x21, x22, [sp, torvalds#32] struct teo_cpu *cpu_data = per_cpu_ptr(&teo_cpus, dev->cpu); ffffffc080ffd010: adrp x19, ffffffc083eb5000 <cpu_devices+0x78> ffffffc080ffd014: add x19, x19, #0xbb0 ffffffc080ffd018: ldr w3, [x20, #4] dev->last_state_idx = state; to static void teo_reflect(struct cpuidle_device *dev, int state) { ffffffc080ffd034: hint #0x19 ffffffc080ffd038: stp x29, x30, [sp, #-48]! ffffffc080ffd03c: add x29, sp, #0x0 ffffffc080ffd040: stp x19, x20, [sp, torvalds#16] ffffffc080ffd044: orr x20, xzr, x0 struct teo_cpu *cpu_data = this_cpu_ptr(&teo_cpus); ffffffc080ffd048: adrp x19, ffffffc083eb5000 <cpu_devices+0x78> { ffffffc080ffd04c: stp x21, x22, [sp, torvalds#32] struct teo_cpu *cpu_data = this_cpu_ptr(&teo_cpus); ffffffc080ffd050: add x19, x19, #0xbb0 dev->last_state_idx = state; This saves us: adrp x2, ffffffc0848c0000 <gicv5_global_data+0x28> add x0, x2, #0xc20 ldr w3, [x20, #4] Signed-off-by: Christian Loehle <christian.loehle@arm.com> [ rjw: Subject tweak ] Link: https://patch.msgid.link/20251110120819.714560-1-christian.loehle@arm.com Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

Do not use memcpy() to extract syscall arguments from struct pt_regs but rather just perform direct assignments. Update syscall_set_arguments() too to keep syscall_get_arguments() and syscall_set_arguments() in sync. With Generic Entry patch[1] and turn on audit, the performance benchmarks from perf bench basic syscall on kunpeng920 gives roughly a 1% performance uplift. | Metric | W/O this patch | With this patch | Change | | ---------- | -------------- | --------------- | --------- | | Total time | 2.241 [sec] | 2.211 [sec] | ↓1.36% | | usecs/op | 0.224157 | 0.221146 | ↓1.36% | | ops/sec | 4,461,157 | 4,501,409 | ↑0.9% | Disassembly shows that using direct assignment causes syscall_set_arguments() to be inlined and cuts the instruction count by five or six compared to memcpy(). Because __audit_syscall_entry() only uses four syscall arguments, the compiler has also elided the copy of regs->regs[4] and regs->regs[5]. Before: <syscall_get_arguments.constprop.0>: aa0103e2 mov x2, x1 91002003 add x3, x0, #0x8 f9408804 ldr x4, [x0, torvalds#272] f8008444 str x4, [x2], torvalds#8 a9409404 ldp x4, x5, [x0, torvalds#8] a9009424 stp x4, x5, [x1, torvalds#8] a9418400 ldp x0, x1, [x0, torvalds#24] a9010440 stp x0, x1, [x2, torvalds#16] f9401060 ldr x0, [x3, torvalds#32] f9001040 str x0, [x2, torvalds#32] d65f03c0 ret d503201f nop After: a9408e82 ldp x2, x3, [x20, torvalds#8] 2a1603e0 mov w0, w22 f9400e84 ldr x4, [x20, torvalds#24] f9408a81 ldr x1, [x20, torvalds#272] 9401c4ba bl ffff800080215ca8 <__audit_syscall_entry> This also aligns the implementation with x86 and RISC-V. Link: https://lkml.kernel.org/r/20251201120633.1193122-3-ruanjinjie@huawei.com Link: https://lore.kernel.org/all/20251126071446.3234218-1-ruanjinjie@huawei.com/ [1] Signed-off-by: Jinjie Ruan <ruanjinjie@huawei.com> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Charlie Jenkins <charlie@rivosinc.com> Cc: Christian Zankel <chris@zankel.net> Cc: "Dmitry V. Levin" <ldv@strace.io> Cc: Helge Deller <deller@gmx.de> Cc: Maciej W. Rozycki <macro@orcam.me.uk> Cc: Marc Rutland <mark.rutland@arm.com> Cc: Max Filippov <jcmvbkbc@gmail.com> Cc: Russell King (Oracle) <rmk+kernel@armlinux.org.uk> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Thomas Gleinxer <tglx@linutronix.de> Cc: Will Deacon <will@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

The cpuidle governor callbacks for update, select and reflect are always running on the actual idle entering/exiting CPU, so use the more optimized this_cpu_ptr() to access the internal teo data. This brings down the latency-critical teo_reflect() from static void teo_reflect(struct cpuidle_device *dev, int state) { ffffffc080ffcff0: hint #0x19 ffffffc080ffcff4: stp x29, x30, [sp, #-48]! struct teo_cpu *cpu_data = per_cpu_ptr(&teo_cpus, dev->cpu); ffffffc080ffcff8: adrp x2, ffffffc0848c0000 <gicv5_global_data+0x28> { ffffffc080ffcffc: add x29, sp, #0x0 ffffffc080ffd000: stp x19, x20, [sp, torvalds#16] ffffffc080ffd004: orr x20, xzr, x0 struct teo_cpu *cpu_data = per_cpu_ptr(&teo_cpus, dev->cpu); ffffffc080ffd008: add x0, x2, #0xc20 { ffffffc080ffd00c: stp x21, x22, [sp, torvalds#32] struct teo_cpu *cpu_data = per_cpu_ptr(&teo_cpus, dev->cpu); ffffffc080ffd010: adrp x19, ffffffc083eb5000 <cpu_devices+0x78> ffffffc080ffd014: add x19, x19, #0xbb0 ffffffc080ffd018: ldr w3, [x20, #4] dev->last_state_idx = state; to static void teo_reflect(struct cpuidle_device *dev, int state) { ffffffc080ffd034: hint #0x19 ffffffc080ffd038: stp x29, x30, [sp, #-48]! ffffffc080ffd03c: add x29, sp, #0x0 ffffffc080ffd040: stp x19, x20, [sp, torvalds#16] ffffffc080ffd044: orr x20, xzr, x0 struct teo_cpu *cpu_data = this_cpu_ptr(&teo_cpus); ffffffc080ffd048: adrp x19, ffffffc083eb5000 <cpu_devices+0x78> { ffffffc080ffd04c: stp x21, x22, [sp, torvalds#32] struct teo_cpu *cpu_data = this_cpu_ptr(&teo_cpus); ffffffc080ffd050: add x19, x19, #0xbb0 dev->last_state_idx = state; This saves us: adrp x2, ffffffc0848c0000 <gicv5_global_data+0x28> add x0, x2, #0xc20 ldr w3, [x20, #4] Signed-off-by: Christian Loehle <christian.loehle@arm.com> [ rjw: Subject tweak ] Link: https://patch.msgid.link/20251110120819.714560-1-christian.loehle@arm.com Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> (cherry picked from commit 0796ddf git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm.git linux-next) Bug: 450671466 Change-Id: Icb6faa509da6dc282270d763f763bc943d461119 Signed-off-by: Reka Norman <rekanorman@google.com>

Do not use memcpy() to extract syscall arguments from struct pt_regs but rather just perform direct assignments. Update syscall_set_arguments() too to keep syscall_get_arguments() and syscall_set_arguments() in sync. With Generic Entry patch[1] and turn on audit, the performance benchmarks from perf bench basic syscall on kunpeng920 gives roughly a 1% performance uplift. | Metric | W/O this patch | With this patch | Change | | ---------- | -------------- | --------------- | --------- | | Total time | 2.241 [sec] | 2.211 [sec] | ↓1.36% | | usecs/op | 0.224157 | 0.221146 | ↓1.36% | | ops/sec | 4,461,157 | 4,501,409 | ↑0.9% | Disassembly shows that using direct assignment causes syscall_set_arguments() to be inlined and cuts the instruction count by five or six compared to memcpy(). Because __audit_syscall_entry() only uses four syscall arguments, the compiler has also elided the copy of regs->regs[4] and regs->regs[5]. Before: <syscall_get_arguments.constprop.0>: aa0103e2 mov x2, x1 91002003 add x3, x0, #0x8 f9408804 ldr x4, [x0, torvalds#272] f8008444 str x4, [x2], torvalds#8 a9409404 ldp x4, x5, [x0, torvalds#8] a9009424 stp x4, x5, [x1, torvalds#8] a9418400 ldp x0, x1, [x0, torvalds#24] a9010440 stp x0, x1, [x2, torvalds#16] f9401060 ldr x0, [x3, torvalds#32] f9001040 str x0, [x2, torvalds#32] d65f03c0 ret d503201f nop After: a9408e82 ldp x2, x3, [x20, torvalds#8] 2a1603e0 mov w0, w22 f9400e84 ldr x4, [x20, torvalds#24] f9408a81 ldr x1, [x20, torvalds#272] 9401c4ba bl ffff800080215ca8 <__audit_syscall_entry> This also aligns the implementation with x86 and RISC-V. Link: https://lkml.kernel.org/r/20251201120633.1193122-3-ruanjinjie@huawei.com Link: https://lore.kernel.org/all/20251126071446.3234218-1-ruanjinjie@huawei.com/ [1] Signed-off-by: Jinjie Ruan <ruanjinjie@huawei.com> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Charlie Jenkins <charlie@rivosinc.com> Cc: Christian Zankel <chris@zankel.net> Cc: "Dmitry V. Levin" <ldv@strace.io> Cc: Helge Deller <deller@gmx.de> Cc: Maciej W. Rozycki <macro@orcam.me.uk> Cc: Marc Rutland <mark.rutland@arm.com> Cc: Max Filippov <jcmvbkbc@gmail.com> Cc: Russell King (Oracle) <rmk+kernel@armlinux.org.uk> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Thomas Gleinxer <tglx@linutronix.de> Cc: Will Deacon <will@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

Do not use memcpy() to extract syscall arguments from struct pt_regs but rather just perform direct assignments. Update syscall_set_arguments() too to keep syscall_get_arguments() and syscall_set_arguments() in sync. With Generic Entry patch[1] and turn on audit, the performance benchmarks from perf bench basic syscall on kunpeng920 gives roughly a 1% performance uplift. | Metric | W/O this patch | With this patch | Change | | ---------- | -------------- | --------------- | --------- | | Total time | 2.241 [sec] | 2.211 [sec] | ↓1.36% | | usecs/op | 0.224157 | 0.221146 | ↓1.36% | | ops/sec | 4,461,157 | 4,501,409 | ↑0.9% | Disassembly shows that using direct assignment causes syscall_set_arguments() to be inlined and cuts the instruction count by five or six compared to memcpy(). Because __audit_syscall_entry() only uses four syscall arguments, the compiler has also elided the copy of regs->regs[4] and regs->regs[5]. Before: <syscall_get_arguments.constprop.0>: aa0103e2 mov x2, x1 91002003 add x3, x0, #0x8 f9408804 ldr x4, [x0, torvalds#272] f8008444 str x4, [x2], torvalds#8 a9409404 ldp x4, x5, [x0, torvalds#8] a9009424 stp x4, x5, [x1, torvalds#8] a9418400 ldp x0, x1, [x0, torvalds#24] a9010440 stp x0, x1, [x2, torvalds#16] f9401060 ldr x0, [x3, torvalds#32] f9001040 str x0, [x2, torvalds#32] d65f03c0 ret d503201f nop After: a9408e82 ldp x2, x3, [x20, torvalds#8] 2a1603e0 mov w0, w22 f9400e84 ldr x4, [x20, torvalds#24] f9408a81 ldr x1, [x20, torvalds#272] 9401c4ba bl ffff800080215ca8 <__audit_syscall_entry> This also aligns the implementation with x86 and RISC-V. [1]: https://lore.kernel.org/all/20251126071446.3234218-1-ruanjinjie@huawei.com/ Signed-off-by: Jinjie Ruan <ruanjinjie@huawei.com> Signed-off-by: Will Deacon <will@kernel.org>

Do not use memcpy() to extract syscall arguments from struct pt_regs but rather just perform direct assignments. Update syscall_set_arguments() too to keep syscall_get_arguments() and syscall_set_arguments() in sync. With Generic Entry patch[1] and turn on audit, the performance benchmarks from perf bench basic syscall on kunpeng920 gives roughly a 1% performance uplift. | Metric | W/O this patch | With this patch | Change | | ---------- | -------------- | --------------- | --------- | | Total time | 2.241 [sec] | 2.211 [sec] | ↓1.36% | | usecs/op | 0.224157 | 0.221146 | ↓1.36% | | ops/sec | 4,461,157 | 4,501,409 | ↑0.9% | Disassembly shows that using direct assignment causes syscall_set_arguments() to be inlined and cuts the instruction count by five or six compared to memcpy(). Because __audit_syscall_entry() only uses four syscall arguments, the compiler has also elided the copy of regs->regs[4] and regs->regs[5]. Before: <syscall_get_arguments.constprop.0>: aa0103e2 mov x2, x1 91002003 add x3, x0, #0x8 f9408804 ldr x4, [x0, torvalds#272] f8008444 str x4, [x2], torvalds#8 a9409404 ldp x4, x5, [x0, torvalds#8] a9009424 stp x4, x5, [x1, torvalds#8] a9418400 ldp x0, x1, [x0, torvalds#24] a9010440 stp x0, x1, [x2, torvalds#16] f9401060 ldr x0, [x3, torvalds#32] f9001040 str x0, [x2, torvalds#32] d65f03c0 ret d503201f nop After: a9408e82 ldp x2, x3, [x20, torvalds#8] 2a1603e0 mov w0, w22 f9400e84 ldr x4, [x20, torvalds#24] f9408a81 ldr x1, [x20, torvalds#272] 9401c4ba bl ffff800080215ca8 <__audit_syscall_entry> This also aligns the implementation with x86 and RISC-V. Link: https://lkml.kernel.org/r/20251201120633.1193122-3-ruanjinjie@huawei.com Link: https://lore.kernel.org/all/20251126071446.3234218-1-ruanjinjie@huawei.com/ [1] Signed-off-by: Jinjie Ruan <ruanjinjie@huawei.com> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Charlie Jenkins <charlie@rivosinc.com> Cc: Christian Zankel <chris@zankel.net> Cc: "Dmitry V. Levin" <ldv@strace.io> Cc: Helge Deller <deller@gmx.de> Cc: Maciej W. Rozycki <macro@orcam.me.uk> Cc: Marc Rutland <mark.rutland@arm.com> Cc: Max Filippov <jcmvbkbc@gmail.com> Cc: Russell King (Oracle) <rmk+kernel@armlinux.org.uk> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Thomas Gleinxer <tglx@linutronix.de> Cc: Will Deacon <will@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

The cpuidle governor callbacks for update, select and reflect are always running on the actual idle entering/exiting CPU, so use the more optimized this_cpu_ptr() to access the internal teo data. This brings down the latency-critical teo_reflect() from static void teo_reflect(struct cpuidle_device *dev, int state) { ffffffc080ffcff0: hint #0x19 ffffffc080ffcff4: stp x29, x30, [sp, #-48]! struct teo_cpu *cpu_data = per_cpu_ptr(&teo_cpus, dev->cpu); ffffffc080ffcff8: adrp x2, ffffffc0848c0000 <gicv5_global_data+0x28> { ffffffc080ffcffc: add x29, sp, #0x0 ffffffc080ffd000: stp x19, x20, [sp, torvalds#16] ffffffc080ffd004: orr x20, xzr, x0 struct teo_cpu *cpu_data = per_cpu_ptr(&teo_cpus, dev->cpu); ffffffc080ffd008: add x0, x2, #0xc20 { ffffffc080ffd00c: stp x21, x22, [sp, torvalds#32] struct teo_cpu *cpu_data = per_cpu_ptr(&teo_cpus, dev->cpu); ffffffc080ffd010: adrp x19, ffffffc083eb5000 <cpu_devices+0x78> ffffffc080ffd014: add x19, x19, #0xbb0 ffffffc080ffd018: ldr w3, [x20, #4] dev->last_state_idx = state; to static void teo_reflect(struct cpuidle_device *dev, int state) { ffffffc080ffd034: hint #0x19 ffffffc080ffd038: stp x29, x30, [sp, #-48]! ffffffc080ffd03c: add x29, sp, #0x0 ffffffc080ffd040: stp x19, x20, [sp, torvalds#16] ffffffc080ffd044: orr x20, xzr, x0 struct teo_cpu *cpu_data = this_cpu_ptr(&teo_cpus); ffffffc080ffd048: adrp x19, ffffffc083eb5000 <cpu_devices+0x78> { ffffffc080ffd04c: stp x21, x22, [sp, torvalds#32] struct teo_cpu *cpu_data = this_cpu_ptr(&teo_cpus); ffffffc080ffd050: add x19, x19, #0xbb0 dev->last_state_idx = state; This saves us: adrp x2, ffffffc0848c0000 <gicv5_global_data+0x28> add x0, x2, #0xc20 ldr w3, [x20, #4] Signed-off-by: Christian Loehle <christian.loehle@arm.com> [ rjw: Subject tweak ] Link: https://patch.msgid.link/20251110120819.714560-1-christian.loehle@arm.com Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

Updated README for MarkDown (This is not a final version but a draft).

9650915

ghost reviewed Mar 29, 2012
View reviewed changes

This pull request was closed.

Provide feedback

Saved searches

Use saved searches to filter your results more quickly

Uh oh!

Updated README for MarkDown (This is not a final version but a draft). #16

Updated README for MarkDown (This is not a final version but a draft). #16

Uh oh!

ghost commented Mar 29, 2012

Uh oh!

ghost Mar 29, 2012

Uh oh!

ismaell commented May 30, 2012

Uh oh!

ghost commented May 30, 2012

Uh oh!

Reviewers

Assignees

Labels

Projects

Milestone

Development

Uh oh!

1 participant

Updated README for MarkDown (This is not a final version but a draft). #16

Updated README for MarkDown (This is not a final version but a draft). #16

Uh oh!

Conversation

ghost commented Mar 29, 2012

Uh oh!

ghost Mar 29, 2012

Choose a reason for hiding this comment

Uh oh!

ismaell commented May 30, 2012

Uh oh!

ghost commented May 30, 2012

Uh oh!

Reviewers

Assignees

Labels

Projects

Milestone

Development

Uh oh!

1 participant