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Turing #2
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The GSP booter firmware in Turing and GA100 includes a third memory section called "NMEM", which is non-secure IMEM. This section must be loaded separately from DMEM and secure IMEM, but only if it actually exists. Signed-off-by: Timur Tabi <ttabi@nvidia.com>
The Turing/GA100 version of Booter is slightly different from the GA102+ version. The headers are the same, but different fields of the headers are used to identify the IMEM section. In addition, there is an NMEM section on Turing/GA100. Signed-off-by: Timur Tabi <ttabi@nvidia.com>
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With KASAN enabled, it is possible to get a slab out of bounds during mount to ksmbd due to missing check in parse_server_interfaces() (see below): BUG: KASAN: slab-out-of-bounds in parse_server_interfaces+0x14ee/0x1880 [cifs] Read of size 4 at addr ffff8881433dba98 by task mount/9827 CPU: 5 UID: 0 PID: 9827 Comm: mount Tainted: G OE 6.16.0-rc2-kasan #2 PREEMPT(voluntary) Tainted: [O]=OOT_MODULE, [E]=UNSIGNED_MODULE Hardware name: Dell Inc. Precision Tower 3620/0MWYPT, BIOS 2.13.1 06/14/2019 Call Trace: <TASK> dump_stack_lvl+0x9f/0xf0 print_report+0xd1/0x670 __virt_addr_valid+0x22c/0x430 ? parse_server_interfaces+0x14ee/0x1880 [cifs] ? kasan_complete_mode_report_info+0x2a/0x1f0 ? parse_server_interfaces+0x14ee/0x1880 [cifs] kasan_report+0xd6/0x110 parse_server_interfaces+0x14ee/0x1880 [cifs] __asan_report_load_n_noabort+0x13/0x20 parse_server_interfaces+0x14ee/0x1880 [cifs] ? __pfx_parse_server_interfaces+0x10/0x10 [cifs] ? trace_hardirqs_on+0x51/0x60 SMB3_request_interfaces+0x1ad/0x3f0 [cifs] ? __pfx_SMB3_request_interfaces+0x10/0x10 [cifs] ? SMB2_tcon+0x23c/0x15d0 [cifs] smb3_qfs_tcon+0x173/0x2b0 [cifs] ? __pfx_smb3_qfs_tcon+0x10/0x10 [cifs] ? cifs_get_tcon+0x105d/0x2120 [cifs] ? do_raw_spin_unlock+0x5d/0x200 ? cifs_get_tcon+0x105d/0x2120 [cifs] ? __pfx_smb3_qfs_tcon+0x10/0x10 [cifs] cifs_mount_get_tcon+0x369/0xb90 [cifs] ? dfs_cache_find+0xe7/0x150 [cifs] dfs_mount_share+0x985/0x2970 [cifs] ? check_path.constprop.0+0x28/0x50 ? save_trace+0x54/0x370 ? __pfx_dfs_mount_share+0x10/0x10 [cifs] ? __lock_acquire+0xb82/0x2ba0 ? __kasan_check_write+0x18/0x20 cifs_mount+0xbc/0x9e0 [cifs] ? __pfx_cifs_mount+0x10/0x10 [cifs] ? do_raw_spin_unlock+0x5d/0x200 ? cifs_setup_cifs_sb+0x29d/0x810 [cifs] cifs_smb3_do_mount+0x263/0x1990 [cifs] Reported-by: Namjae Jeon <linkinjeon@kernel.org> Tested-by: Namjae Jeon <linkinjeon@kernel.org> Cc: stable@vger.kernel.org Signed-off-by: Steve French <stfrench@microsoft.com>
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The commit under the Fixes tag added a netdev_assert_locked() in bnxt_free_ntp_fltrs(). The lock should be held during normal run-time but the assert will be triggered (see below) during bnxt_remove_one() which should not need the lock. The netdev is already unregistered by then. Fix it by calling netdev_assert_locked_or_invisible() which will not assert if the netdev is unregistered. WARNING: CPU: 5 PID: 2241 at ./include/net/netdev_lock.h:17 bnxt_free_ntp_fltrs+0xf8/0x100 [bnxt_en] Modules linked in: rpcrdma rdma_cm iw_cm ib_cm configfs ib_core bnxt_en(-) bridge stp llc x86_pkg_temp_thermal xfs tg3 [last unloaded: bnxt_re] CPU: 5 UID: 0 PID: 2241 Comm: rmmod Tainted: G S W 6.16.0 #2 PREEMPT(voluntary) Tainted: [S]=CPU_OUT_OF_SPEC, [W]=WARN Hardware name: Dell Inc. PowerEdge R730/072T6D, BIOS 2.4.3 01/17/2017 RIP: 0010:bnxt_free_ntp_fltrs+0xf8/0x100 [bnxt_en] Code: 41 5c 41 5d 41 5e 41 5f c3 cc cc cc cc 48 8b 47 60 be ff ff ff ff 48 8d b8 28 0c 00 00 e8 d0 cf 41 c3 85 c0 0f 85 2e ff ff ff <0f> 0b e9 27 ff ff ff 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 RSP: 0018:ffffa92082387da0 EFLAGS: 00010246 RAX: 0000000000000000 RBX: ffff9e5b593d8000 RCX: 0000000000000001 RDX: 0000000000000001 RSI: ffffffff83dc9a70 RDI: ffffffff83e1a1cf RBP: ffff9e5b593d8c80 R08: 0000000000000000 R09: ffffffff8373a2b3 R10: 000000008100009f R11: 0000000000000001 R12: 0000000000000001 R13: ffffffffc01c4478 R14: dead000000000122 R15: dead000000000100 FS: 00007f3a8a52c740(0000) GS:ffff9e631ad1c000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000055bb289419c8 CR3: 000000011274e001 CR4: 00000000003706f0 Call Trace: <TASK> bnxt_remove_one+0x57/0x180 [bnxt_en] pci_device_remove+0x39/0xc0 device_release_driver_internal+0xa5/0x130 driver_detach+0x42/0x90 bus_remove_driver+0x61/0xc0 pci_unregister_driver+0x38/0x90 bnxt_exit+0xc/0x7d0 [bnxt_en] Fixes: 004b500 ("eth: bnxt: remove most dependencies on RTNL") Reviewed-by: Pavan Chebbi <pavan.chebbi@broadcom.com> Signed-off-by: Michael Chan <michael.chan@broadcom.com> Reviewed-by: Vadim Fedorenko <vadim.fedorenko@linux.dev> Link: https://patch.msgid.link/20250816183850.4125033-1-michael.chan@broadcom.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
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…dlock When a user creates a dualpi2 qdisc it automatically sets a timer. This timer will run constantly and update the qdisc's probability field. The issue is that the timer acquires the qdisc root lock and runs in hardirq. The qdisc root lock is also acquired in dev.c whenever a packet arrives for this qdisc. Since the dualpi2 timer callback runs in hardirq, it may interrupt the packet processing running in softirq. If that happens and it runs on the same CPU, it will acquire the same lock and cause a deadlock. The following splat shows up when running a kernel compiled with lock debugging: [ +0.000224] WARNING: inconsistent lock state [ +0.000224] 6.16.0+ torvalds#10 Not tainted [ +0.000169] -------------------------------- [ +0.000029] inconsistent {IN-HARDIRQ-W} -> {HARDIRQ-ON-W} usage. [ +0.000000] ping/156 [HC0[0]:SC0[2]:HE1:SE0] takes: [ +0.000000] ffff897841242110 (&sch->root_lock_key){?.-.}-{3:3}, at: __dev_queue_xmit+0x86d/0x1140 [ +0.000000] {IN-HARDIRQ-W} state was registered at: [ +0.000000] lock_acquire.part.0+0xb6/0x220 [ +0.000000] _raw_spin_lock+0x31/0x80 [ +0.000000] dualpi2_timer+0x6f/0x270 [ +0.000000] __hrtimer_run_queues+0x1c5/0x360 [ +0.000000] hrtimer_interrupt+0x115/0x260 [ +0.000000] __sysvec_apic_timer_interrupt+0x6d/0x1a0 [ +0.000000] sysvec_apic_timer_interrupt+0x6e/0x80 [ +0.000000] asm_sysvec_apic_timer_interrupt+0x1a/0x20 [ +0.000000] pv_native_safe_halt+0xf/0x20 [ +0.000000] default_idle+0x9/0x10 [ +0.000000] default_idle_call+0x7e/0x1e0 [ +0.000000] do_idle+0x1e8/0x250 [ +0.000000] cpu_startup_entry+0x29/0x30 [ +0.000000] rest_init+0x151/0x160 [ +0.000000] start_kernel+0x6f3/0x700 [ +0.000000] x86_64_start_reservations+0x24/0x30 [ +0.000000] x86_64_start_kernel+0xc8/0xd0 [ +0.000000] common_startup_64+0x13e/0x148 [ +0.000000] irq event stamp: 6884 [ +0.000000] hardirqs last enabled at (6883): [<ffffffffa75700b3>] neigh_resolve_output+0x223/0x270 [ +0.000000] hardirqs last disabled at (6882): [<ffffffffa7570078>] neigh_resolve_output+0x1e8/0x270 [ +0.000000] softirqs last enabled at (6880): [<ffffffffa757006b>] neigh_resolve_output+0x1db/0x270 [ +0.000000] softirqs last disabled at (6884): [<ffffffffa755b533>] __dev_queue_xmit+0x73/0x1140 [ +0.000000] other info that might help us debug this: [ +0.000000] Possible unsafe locking scenario: [ +0.000000] CPU0 [ +0.000000] ---- [ +0.000000] lock(&sch->root_lock_key); [ +0.000000] <Interrupt> [ +0.000000] lock(&sch->root_lock_key); [ +0.000000] *** DEADLOCK *** [ +0.000000] 4 locks held by ping/156: [ +0.000000] #0: ffff897842332e08 (sk_lock-AF_INET){+.+.}-{0:0}, at: raw_sendmsg+0x41e/0xf40 [ +0.000000] #1: ffffffffa816f880 (rcu_read_lock){....}-{1:3}, at: ip_output+0x2c/0x190 [ +0.000000] #2: ffffffffa816f880 (rcu_read_lock){....}-{1:3}, at: ip_finish_output2+0xad/0x950 [ +0.000000] #3: ffffffffa816f840 (rcu_read_lock_bh){....}-{1:3}, at: __dev_queue_xmit+0x73/0x1140 I am able to reproduce it consistently when running the following: tc qdisc add dev lo handle 1: root dualpi2 ping -f 127.0.0.1 To fix it, make the timer run in softirq. Fixes: 320d031 ("sched: Struct definition and parsing of dualpi2 qdisc") Reviewed-by: Jamal Hadi Salim <jhs@mojatatu.com> Signed-off-by: Victor Nogueira <victor@mojatatu.com> Link: https://patch.msgid.link/20250815135317.664993-1-victor@mojatatu.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
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Commit 3c7ac40 ("scsi: ufs: core: Delegate the interrupt service routine to a threaded IRQ handler") introduced an IRQ lock inversion issue. Fix this lock inversion by changing the spin_lock_irq() calls into spin_lock_irqsave() calls in code that can be called either from interrupt context or from thread context. This patch fixes the following lockdep complaint: WARNING: possible irq lock inversion dependency detected 6.12.30-android16-5-maybe-dirty-4k #1 Tainted: G W OE -------------------------------------------------------- kworker/u28:0/12 just changed the state of lock: ffffff881e29dd60 (&hba->clk_gating.lock){-...}-{2:2}, at: ufshcd_release_scsi_cmd+0x60/0x110 but this lock took another, HARDIRQ-unsafe lock in the past: (shost->host_lock){+.+.}-{2:2} and interrupts could create inverse lock ordering between them. other info that might help us debug this: Possible interrupt unsafe locking scenario: CPU0 CPU1 ---- ---- lock(shost->host_lock); local_irq_disable(); lock(&hba->clk_gating.lock); lock(shost->host_lock); <Interrupt> lock(&hba->clk_gating.lock); *** DEADLOCK *** 4 locks held by kworker/u28:0/12: #0: ffffff8800ac6158 ((wq_completion)async){+.+.}-{0:0}, at: process_one_work+0x1bc/0x65c #1: ffffffc085c93d70 ((work_completion)(&entry->work)){+.+.}-{0:0}, at: process_one_work+0x1e4/0x65c #2: ffffff881e29c0e0 (&shost->scan_mutex){+.+.}-{3:3}, at: __scsi_add_device+0x74/0x120 #3: ffffff881960ea00 (&hwq->cq_lock){-...}-{2:2}, at: ufshcd_mcq_poll_cqe_lock+0x28/0x104 the shortest dependencies between 2nd lock and 1st lock: -> (shost->host_lock){+.+.}-{2:2} { HARDIRQ-ON-W at: lock_acquire+0x134/0x2b4 _raw_spin_lock+0x48/0x64 ufshcd_sl_intr+0x4c/0xa08 ufshcd_threaded_intr+0x70/0x12c irq_thread_fn+0x48/0xa8 irq_thread+0x130/0x1ec kthread+0x110/0x134 ret_from_fork+0x10/0x20 SOFTIRQ-ON-W at: lock_acquire+0x134/0x2b4 _raw_spin_lock+0x48/0x64 ufshcd_sl_intr+0x4c/0xa08 ufshcd_threaded_intr+0x70/0x12c irq_thread_fn+0x48/0xa8 irq_thread+0x130/0x1ec kthread+0x110/0x134 ret_from_fork+0x10/0x20 INITIAL USE at: lock_acquire+0x134/0x2b4 _raw_spin_lock+0x48/0x64 ufshcd_sl_intr+0x4c/0xa08 ufshcd_threaded_intr+0x70/0x12c irq_thread_fn+0x48/0xa8 irq_thread+0x130/0x1ec kthread+0x110/0x134 ret_from_fork+0x10/0x20 } ... key at: [<ffffffc085ba1a98>] scsi_host_alloc.__key+0x0/0x10 ... acquired at: _raw_spin_lock_irqsave+0x5c/0x80 __ufshcd_release+0x78/0x118 ufshcd_send_uic_cmd+0xe4/0x118 ufshcd_dme_set_attr+0x88/0x1c8 ufs_google_phy_initialization+0x68/0x418 [ufs] ufs_google_link_startup_notify+0x78/0x27c [ufs] ufshcd_link_startup+0x84/0x720 ufshcd_init+0xf3c/0x1330 ufshcd_pltfrm_init+0x728/0x7d8 ufs_google_probe+0x30/0x84 [ufs] platform_probe+0xa0/0xe0 really_probe+0x114/0x454 __driver_probe_device+0xa4/0x160 driver_probe_device+0x44/0x23c __driver_attach_async_helper+0x60/0xd4 async_run_entry_fn+0x4c/0x17c process_one_work+0x26c/0x65c worker_thread+0x33c/0x498 kthread+0x110/0x134 ret_from_fork+0x10/0x20 -> (&hba->clk_gating.lock){-...}-{2:2} { IN-HARDIRQ-W at: lock_acquire+0x134/0x2b4 _raw_spin_lock_irqsave+0x5c/0x80 ufshcd_release_scsi_cmd+0x60/0x110 ufshcd_compl_one_cqe+0x2c0/0x3f4 ufshcd_mcq_poll_cqe_lock+0xb0/0x104 ufs_google_mcq_intr+0x80/0xa0 [ufs] __handle_irq_event_percpu+0x104/0x32c handle_irq_event+0x40/0x9c handle_fasteoi_irq+0x170/0x2e8 generic_handle_domain_irq+0x58/0x80 gic_handle_irq+0x48/0x104 call_on_irq_stack+0x3c/0x50 do_interrupt_handler+0x7c/0xd8 el1_interrupt+0x34/0x58 el1h_64_irq_handler+0x18/0x24 el1h_64_irq+0x68/0x6c _raw_spin_unlock_irqrestore+0x3c/0x6c debug_object_assert_init+0x16c/0x21c __mod_timer+0x4c/0x48c schedule_timeout+0xd4/0x16c io_schedule_timeout+0x48/0x70 do_wait_for_common+0x100/0x194 wait_for_completion_io_timeout+0x48/0x6c blk_execute_rq+0x124/0x17c scsi_execute_cmd+0x18c/0x3f8 scsi_probe_and_add_lun+0x204/0xd74 __scsi_add_device+0xbc/0x120 ufshcd_async_scan+0x80/0x3c0 async_run_entry_fn+0x4c/0x17c process_one_work+0x26c/0x65c worker_thread+0x33c/0x498 kthread+0x110/0x134 ret_from_fork+0x10/0x20 INITIAL USE at: lock_acquire+0x134/0x2b4 _raw_spin_lock_irqsave+0x5c/0x80 ufshcd_hold+0x34/0x14c ufshcd_send_uic_cmd+0x28/0x118 ufshcd_dme_set_attr+0x88/0x1c8 ufs_google_phy_initialization+0x68/0x418 [ufs] ufs_google_link_startup_notify+0x78/0x27c [ufs] ufshcd_link_startup+0x84/0x720 ufshcd_init+0xf3c/0x1330 ufshcd_pltfrm_init+0x728/0x7d8 ufs_google_probe+0x30/0x84 [ufs] platform_probe+0xa0/0xe0 really_probe+0x114/0x454 __driver_probe_device+0xa4/0x160 driver_probe_device+0x44/0x23c __driver_attach_async_helper+0x60/0xd4 async_run_entry_fn+0x4c/0x17c process_one_work+0x26c/0x65c worker_thread+0x33c/0x498 kthread+0x110/0x134 ret_from_fork+0x10/0x20 } ... key at: [<ffffffc085ba6fe8>] ufshcd_init.__key+0x0/0x10 ... acquired at: mark_lock+0x1c4/0x224 __lock_acquire+0x438/0x2e1c lock_acquire+0x134/0x2b4 _raw_spin_lock_irqsave+0x5c/0x80 ufshcd_release_scsi_cmd+0x60/0x110 ufshcd_compl_one_cqe+0x2c0/0x3f4 ufshcd_mcq_poll_cqe_lock+0xb0/0x104 ufs_google_mcq_intr+0x80/0xa0 [ufs] __handle_irq_event_percpu+0x104/0x32c handle_irq_event+0x40/0x9c handle_fasteoi_irq+0x170/0x2e8 generic_handle_domain_irq+0x58/0x80 gic_handle_irq+0x48/0x104 call_on_irq_stack+0x3c/0x50 do_interrupt_handler+0x7c/0xd8 el1_interrupt+0x34/0x58 el1h_64_irq_handler+0x18/0x24 el1h_64_irq+0x68/0x6c _raw_spin_unlock_irqrestore+0x3c/0x6c debug_object_assert_init+0x16c/0x21c __mod_timer+0x4c/0x48c schedule_timeout+0xd4/0x16c io_schedule_timeout+0x48/0x70 do_wait_for_common+0x100/0x194 wait_for_completion_io_timeout+0x48/0x6c blk_execute_rq+0x124/0x17c scsi_execute_cmd+0x18c/0x3f8 scsi_probe_and_add_lun+0x204/0xd74 __scsi_add_device+0xbc/0x120 ufshcd_async_scan+0x80/0x3c0 async_run_entry_fn+0x4c/0x17c process_one_work+0x26c/0x65c worker_thread+0x33c/0x498 kthread+0x110/0x134 ret_from_fork+0x10/0x20 stack backtrace: CPU: 6 UID: 0 PID: 12 Comm: kworker/u28:0 Tainted: G W OE 6.12.30-android16-5-maybe-dirty-4k #1 ccd4020fe444bdf629efc3b86df6be920b8df7d0 Tainted: [W]=WARN, [O]=OOT_MODULE, [E]=UNSIGNED_MODULE Hardware name: Spacecraft board based on MALIBU (DT) Workqueue: async async_run_entry_fn Call trace: dump_backtrace+0xfc/0x17c show_stack+0x18/0x28 dump_stack_lvl+0x40/0xa0 dump_stack+0x18/0x24 print_irq_inversion_bug+0x2fc/0x304 mark_lock_irq+0x388/0x4fc mark_lock+0x1c4/0x224 __lock_acquire+0x438/0x2e1c lock_acquire+0x134/0x2b4 _raw_spin_lock_irqsave+0x5c/0x80 ufshcd_release_scsi_cmd+0x60/0x110 ufshcd_compl_one_cqe+0x2c0/0x3f4 ufshcd_mcq_poll_cqe_lock+0xb0/0x104 ufs_google_mcq_intr+0x80/0xa0 [ufs dd6f385554e109da094ab91d5f7be18625a2222a] __handle_irq_event_percpu+0x104/0x32c handle_irq_event+0x40/0x9c handle_fasteoi_irq+0x170/0x2e8 generic_handle_domain_irq+0x58/0x80 gic_handle_irq+0x48/0x104 call_on_irq_stack+0x3c/0x50 do_interrupt_handler+0x7c/0xd8 el1_interrupt+0x34/0x58 el1h_64_irq_handler+0x18/0x24 el1h_64_irq+0x68/0x6c _raw_spin_unlock_irqrestore+0x3c/0x6c debug_object_assert_init+0x16c/0x21c __mod_timer+0x4c/0x48c schedule_timeout+0xd4/0x16c io_schedule_timeout+0x48/0x70 do_wait_for_common+0x100/0x194 wait_for_completion_io_timeout+0x48/0x6c blk_execute_rq+0x124/0x17c scsi_execute_cmd+0x18c/0x3f8 scsi_probe_and_add_lun+0x204/0xd74 __scsi_add_device+0xbc/0x120 ufshcd_async_scan+0x80/0x3c0 async_run_entry_fn+0x4c/0x17c process_one_work+0x26c/0x65c worker_thread+0x33c/0x498 kthread+0x110/0x134 ret_from_fork+0x10/0x20 Cc: Neil Armstrong <neil.armstrong@linaro.org> Cc: André Draszik <andre.draszik@linaro.org> Reviewed-by: Peter Wang <peter.wang@mediatek.com> Fixes: 3c7ac40 ("scsi: ufs: core: Delegate the interrupt service routine to a threaded IRQ handler") Signed-off-by: Bart Van Assche <bvanassche@acm.org> Link: https://lore.kernel.org/r/20250815155842.472867-2-bvanassche@acm.org Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
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These iterations require the read lock, otherwise RCU lockdep will splat: ============================= WARNING: suspicious RCU usage 6.17.0-rc3-00014-g31419c045d64 torvalds#6 Tainted: G O ----------------------------- drivers/base/power/main.c:1333 RCU-list traversed in non-reader section!! other info that might help us debug this: rcu_scheduler_active = 2, debug_locks = 1 5 locks held by rtcwake/547: #0: 00000000643ab418 (sb_writers#6){.+.+}-{0:0}, at: file_start_write+0x2b/0x3a #1: 0000000067a0ca88 (&of->mutex#2){+.+.}-{4:4}, at: kernfs_fop_write_iter+0x181/0x24b #2: 00000000631eac40 (kn->active#3){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x191/0x24b #3: 00000000609a1308 (system_transition_mutex){+.+.}-{4:4}, at: pm_suspend+0xaf/0x30b #4: 0000000060c0fdb0 (device_links_srcu){.+.+}-{0:0}, at: device_links_read_lock+0x75/0x98 stack backtrace: CPU: 0 UID: 0 PID: 547 Comm: rtcwake Tainted: G O 6.17.0-rc3-00014-g31419c045d64 torvalds#6 VOLUNTARY Tainted: [O]=OOT_MODULE Stack: 223721b3a80 6089eac6 00000001 00000001 ffffff00 6089eac6 00000535 6086e528 721b3ac0 6003c294 00000000 60031fc0 Call Trace: [<600407ed>] show_stack+0x10e/0x127 [<6003c294>] dump_stack_lvl+0x77/0xc6 [<6003c2fd>] dump_stack+0x1a/0x20 [<600bc2f8>] lockdep_rcu_suspicious+0x116/0x13e [<603d8ea1>] dpm_async_suspend_superior+0x117/0x17e [<603d980f>] device_suspend+0x528/0x541 [<603da24b>] dpm_suspend+0x1a2/0x267 [<603da837>] dpm_suspend_start+0x5d/0x72 [<600ca0c9>] suspend_devices_and_enter+0xab/0x736 [...] Add the fourth argument to the iteration to annotate this and avoid the splat. Fixes: 0679963 ("PM: sleep: Make async suspend handle suppliers like parents") Fixes: ed18738 ("PM: sleep: Make async resume handle consumers like children") Signed-off-by: Johannes Berg <johannes.berg@intel.com> Link: https://patch.msgid.link/20250826134348.aba79f6e6299.I9ecf55da46ccf33778f2c018a82e1819d815b348@changeid Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
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With CONFIG_DEBUG_OBJECTS_TIMERS unloading hfcpci module leads to the following splat: [ 250.215892] ODEBUG: assert_init not available (active state 0) object: ffffffffc01a3dc0 object type: timer_list hint: 0x0 [ 250.217520] WARNING: CPU: 0 PID: 233 at lib/debugobjects.c:612 debug_print_object+0x1b6/0x2c0 [ 250.218775] Modules linked in: hfcpci(-) mISDN_core [ 250.219537] CPU: 0 UID: 0 PID: 233 Comm: rmmod Not tainted 6.17.0-rc2-g6f713187ac98 #2 PREEMPT(voluntary) [ 250.220940] Hardware name: QEMU Ubuntu 24.04 PC (i440FX + PIIX, 1996), BIOS 1.16.3-debian-1.16.3-2 04/01/2014 [ 250.222377] RIP: 0010:debug_print_object+0x1b6/0x2c0 [ 250.223131] Code: fc ff df 48 89 fa 48 c1 ea 03 80 3c 02 00 75 4f 41 56 48 8b 14 dd a0 4e 01 9f 48 89 ee 48 c7 c7 20 46 01 9f e8 cb 84d [ 250.225805] RSP: 0018:ffff888015ea7c08 EFLAGS: 00010286 [ 250.226608] RAX: 0000000000000000 RBX: 0000000000000005 RCX: ffffffff9be93a95 [ 250.227708] RDX: 1ffff1100d945138 RSI: 0000000000000008 RDI: ffff88806ca289c0 [ 250.228993] RBP: ffffffff9f014a00 R08: 0000000000000001 R09: ffffed1002bd4f39 [ 250.230043] R10: ffff888015ea79cf R11: 0000000000000001 R12: 0000000000000001 [ 250.231185] R13: ffffffff9eea0520 R14: 0000000000000000 R15: ffff888015ea7cc8 [ 250.232454] FS: 00007f3208f01540(0000) GS:ffff8880caf5a000(0000) knlGS:0000000000000000 [ 250.233851] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 250.234856] CR2: 00007f32090a7421 CR3: 0000000004d63000 CR4: 00000000000006f0 [ 250.236117] Call Trace: [ 250.236599] <TASK> [ 250.236967] ? trace_irq_enable.constprop.0+0xd4/0x130 [ 250.237920] debug_object_assert_init+0x1f6/0x310 [ 250.238762] ? __pfx_debug_object_assert_init+0x10/0x10 [ 250.239658] ? __lock_acquire+0xdea/0x1c70 [ 250.240369] __try_to_del_timer_sync+0x69/0x140 [ 250.241172] ? __pfx___try_to_del_timer_sync+0x10/0x10 [ 250.242058] ? __timer_delete_sync+0xc6/0x120 [ 250.242842] ? lock_acquire+0x30/0x80 [ 250.243474] ? __timer_delete_sync+0xc6/0x120 [ 250.244262] __timer_delete_sync+0x98/0x120 [ 250.245015] HFC_cleanup+0x10/0x20 [hfcpci] [ 250.245704] __do_sys_delete_module+0x348/0x510 [ 250.246461] ? __pfx___do_sys_delete_module+0x10/0x10 [ 250.247338] do_syscall_64+0xc1/0x360 [ 250.247924] entry_SYSCALL_64_after_hwframe+0x77/0x7f Fix this by initializing hfc_tl timer with DEFINE_TIMER macro. Also, use mod_timer instead of manual timeout update. Fixes: 87c5fa1 ("mISDN: Add different different timer settings for hfc-pci") Fixes: 175302f ("mISDN: hfcpci: Fix use-after-free bug in hfcpci_softirq") Signed-off-by: Vladimir Riabchun <ferr.lambarginio@gmail.com> Link: https://patch.msgid.link/aKiy2D_LiWpQ5kXq@vova-pc Signed-off-by: Jakub Kicinski <kuba@kernel.org>
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If preparing a write bio fails then blk_zone_wplug_bio_work() calls
bio_endio() with zwplug->lock held. If a device mapper driver is stacked
on top of the zoned block device then this results in nested locking of
zwplug->lock. The resulting lockdep complaint is a false positive
because this is nested locking and not recursive locking. Suppress this
false positive by calling blk_zone_wplug_bio_io_error() without holding
zwplug->lock. This is safe because no code in
blk_zone_wplug_bio_io_error() depends on zwplug->lock being held. This
patch suppresses the following lockdep complaint:
WARNING: possible recursive locking detected
--------------------------------------------
kworker/3:0H/46 is trying to acquire lock:
ffffff882968b830 (&zwplug->lock){-...}-{2:2}, at: blk_zone_write_plug_bio_endio+0x64/0x1f0
but task is already holding lock:
ffffff88315bc230 (&zwplug->lock){-...}-{2:2}, at: blk_zone_wplug_bio_work+0x8c/0x48c
other info that might help us debug this:
Possible unsafe locking scenario:
CPU0
----
lock(&zwplug->lock);
lock(&zwplug->lock);
*** DEADLOCK ***
May be due to missing lock nesting notation
3 locks held by kworker/3:0H/46:
#0: ffffff8809486758 ((wq_completion)sdd_zwplugs){+.+.}-{0:0}, at: process_one_work+0x1bc/0x65c
#1: ffffffc085de3d70 ((work_completion)(&zwplug->bio_work)){+.+.}-{0:0}, at: process_one_work+0x1e4/0x65c
#2: ffffff88315bc230 (&zwplug->lock){-...}-{2:2}, at: blk_zone_wplug_bio_work+0x8c/0x48c
stack backtrace:
CPU: 3 UID: 0 PID: 46 Comm: kworker/3:0H Tainted: G W OE 6.12.38-android16-5-maybe-dirty-4k #1 8b362b6f76e3645a58cd27d86982bce10d150025
Tainted: [W]=WARN, [O]=OOT_MODULE, [E]=UNSIGNED_MODULE
Hardware name: Spacecraft board based on MALIBU (DT)
Workqueue: sdd_zwplugs blk_zone_wplug_bio_work
Call trace:
dump_backtrace+0xfc/0x17c
show_stack+0x18/0x28
dump_stack_lvl+0x40/0xa0
dump_stack+0x18/0x24
print_deadlock_bug+0x38c/0x398
__lock_acquire+0x13e8/0x2e1c
lock_acquire+0x134/0x2b4
_raw_spin_lock_irqsave+0x5c/0x80
blk_zone_write_plug_bio_endio+0x64/0x1f0
bio_endio+0x9c/0x240
__dm_io_complete+0x214/0x260
clone_endio+0xe8/0x214
bio_endio+0x218/0x240
blk_zone_wplug_bio_work+0x204/0x48c
process_one_work+0x26c/0x65c
worker_thread+0x33c/0x498
kthread+0x110/0x134
ret_from_fork+0x10/0x20
Cc: stable@vger.kernel.org
Cc: Damien Le Moal <dlemoal@kernel.org>
Cc: Christoph Hellwig <hch@lst.de>
Fixes: dd291d7 ("block: Introduce zone write plugging")
Signed-off-by: Bart Van Assche <bvanassche@acm.org>
Reviewed-by: Damien Le Moal <dlemoal@kernel.org>
Link: https://lore.kernel.org/r/20250825182720.1697203-1-bvanassche@acm.org
Signed-off-by: Jens Axboe <axboe@kernel.dk>
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…ux/kernel/git/kvmarm/kvmarm into HEAD KVM/arm64 changes for 6.17, take #2 - Correctly handle 'invariant' system registers for protected VMs - Improved handling of VNCR data aborts, including external aborts - Fixes for handling of FEAT_RAS for NV guests, providing a sane fault context during SEA injection and preventing the use of RASv1p1 fault injection hardware - Ensure that page table destruction when a VM is destroyed gives an opportunity to reschedule - Large fix to KVM's infrastructure for managing guest context loaded on the CPU, addressing issues where the output of AT emulation doesn't get reflected to the guest - Fix AT S12 emulation to actually perform stage-2 translation when necessary - Avoid attempting vLPI irqbypass when GICv4 has been explicitly disabled for a VM - Minor KVM + selftest fixes
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In gicv5_irs_of_init_affinity() a WARN_ON() is triggered if:
1) a phandle in the "cpus" property does not correspond to a valid OF
node
2 a CPU logical id does not exist for a given OF cpu_node
#1 is a firmware bug and should be reported as such but does not warrant a
WARN_ON() backtrace.
#2 is not necessarily an error condition (eg a kernel can be booted with
nr_cpus=X limiting the number of cores artificially) and therefore there
is no reason to clutter the kernel log with WARN_ON() output when the
condition is hit.
Rework the IRS affinity parsing code to remove undue WARN_ON()s thus
making it less noisy.
Signed-off-by: Lorenzo Pieralisi <lpieralisi@kernel.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/all/20250814094138.1611017-1-lpieralisi@kernel.org
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When the "proxy" option is enabled on a VXLAN device, the device will suppress ARP requests and IPv6 Neighbor Solicitation messages if it is able to reply on behalf of the remote host. That is, if a matching and valid neighbor entry is configured on the VXLAN device whose MAC address is not behind the "any" remote (0.0.0.0 / ::). The code currently assumes that the FDB entry for the neighbor's MAC address points to a valid remote destination, but this is incorrect if the entry is associated with an FDB nexthop group. This can result in a NPD [1][3] which can be reproduced using [2][4]. Fix by checking that the remote destination exists before dereferencing it. [1] BUG: kernel NULL pointer dereference, address: 0000000000000000 [...] CPU: 4 UID: 0 PID: 365 Comm: arping Not tainted 6.17.0-rc2-virtme-g2a89cb21162c #2 PREEMPT(voluntary) Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.17.0-4.fc41 04/01/2014 RIP: 0010:vxlan_xmit+0xb58/0x15f0 [...] Call Trace: <TASK> dev_hard_start_xmit+0x5d/0x1c0 __dev_queue_xmit+0x246/0xfd0 packet_sendmsg+0x113a/0x1850 __sock_sendmsg+0x38/0x70 __sys_sendto+0x126/0x180 __x64_sys_sendto+0x24/0x30 do_syscall_64+0xa4/0x260 entry_SYSCALL_64_after_hwframe+0x4b/0x53 [2] #!/bin/bash ip address add 192.0.2.1/32 dev lo ip nexthop add id 1 via 192.0.2.2 fdb ip nexthop add id 10 group 1 fdb ip link add name vx0 up type vxlan id 10010 local 192.0.2.1 dstport 4789 proxy ip neigh add 192.0.2.3 lladdr 00:11:22:33:44:55 nud perm dev vx0 bridge fdb add 00:11:22:33:44:55 dev vx0 self static nhid 10 arping -b -c 1 -s 192.0.2.1 -I vx0 192.0.2.3 [3] BUG: kernel NULL pointer dereference, address: 0000000000000000 [...] CPU: 13 UID: 0 PID: 372 Comm: ndisc6 Not tainted 6.17.0-rc2-virtmne-g6ee90cb26014 #3 PREEMPT(voluntary) Hardware name: QEMU Standard PC (i440FX + PIIX, 1v996), BIOS 1.17.0-4.fc41 04/01/2x014 RIP: 0010:vxlan_xmit+0x803/0x1600 [...] Call Trace: <TASK> dev_hard_start_xmit+0x5d/0x1c0 __dev_queue_xmit+0x246/0xfd0 ip6_finish_output2+0x210/0x6c0 ip6_finish_output+0x1af/0x2b0 ip6_mr_output+0x92/0x3e0 ip6_send_skb+0x30/0x90 rawv6_sendmsg+0xe6e/0x12e0 __sock_sendmsg+0x38/0x70 __sys_sendto+0x126/0x180 __x64_sys_sendto+0x24/0x30 do_syscall_64+0xa4/0x260 entry_SYSCALL_64_after_hwframe+0x4b/0x53 RIP: 0033:0x7f383422ec77 [4] #!/bin/bash ip address add 2001:db8:1::1/128 dev lo ip nexthop add id 1 via 2001:db8:1::1 fdb ip nexthop add id 10 group 1 fdb ip link add name vx0 up type vxlan id 10010 local 2001:db8:1::1 dstport 4789 proxy ip neigh add 2001:db8:1::3 lladdr 00:11:22:33:44:55 nud perm dev vx0 bridge fdb add 00:11:22:33:44:55 dev vx0 self static nhid 10 ndisc6 -r 1 -s 2001:db8:1::1 -w 1 2001:db8:1::3 vx0 Fixes: 1274e1c ("vxlan: ecmp support for mac fdb entries") Reviewed-by: Petr Machata <petrm@nvidia.com> Signed-off-by: Ido Schimmel <idosch@nvidia.com> Reviewed-by: Nikolay Aleksandrov <razor@blackwall.org> Link: https://patch.msgid.link/20250901065035.159644-3-idosch@nvidia.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
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Ido Schimmel says:
====================
vxlan: Fix NPDs when using nexthop objects
With FDB nexthop groups, VXLAN FDB entries do not necessarily point to
a remote destination but rather to an FDB nexthop group. This means that
first_remote_{rcu,rtnl}() can return NULL and a few places in the driver
were not ready for that, resulting in NULL pointer dereferences.
Patches #1-#2 fix these NPDs.
Note that vxlan_fdb_find_uc() still dereferences the remote returned by
first_remote_rcu() without checking that it is not NULL, but this
function is only invoked by a single driver which vetoes the creation of
FDB nexthop groups. I will patch this in net-next to make the code less
fragile.
Patch #3 adds a selftests which exercises these code paths and tests
basic Tx functionality with FDB nexthop groups. I verified that the test
crashes the kernel without the first two patches.
====================
Link: https://patch.msgid.link/20250901065035.159644-1-idosch@nvidia.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
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When transmitting a PTP frame which is timestamp using 2 step, the following warning appears if CONFIG_PROVE_LOCKING is enabled: ============================= [ BUG: Invalid wait context ] 6.17.0-rc1-00326-ge6160462704e torvalds#427 Not tainted ----------------------------- ptp4l/119 is trying to lock: c2a44ed4 (&vsc8531->ts_lock){+.+.}-{3:3}, at: vsc85xx_txtstamp+0x50/0xac other info that might help us debug this: context-{4:4} 4 locks held by ptp4l/119: #0: c145f068 (rcu_read_lock_bh){....}-{1:2}, at: __dev_queue_xmit+0x58/0x1440 #1: c29df974 (dev->qdisc_tx_busylock ?: &qdisc_tx_busylock){+...}-{2:2}, at: __dev_queue_xmit+0x5c4/0x1440 #2: c2aaaad0 (_xmit_ETHER#2){+.-.}-{2:2}, at: sch_direct_xmit+0x108/0x350 #3: c2aac170 (&lan966x->tx_lock){+.-.}-{2:2}, at: lan966x_port_xmit+0xd0/0x350 stack backtrace: CPU: 0 UID: 0 PID: 119 Comm: ptp4l Not tainted 6.17.0-rc1-00326-ge6160462704e torvalds#427 NONE Hardware name: Generic DT based system Call trace: unwind_backtrace from show_stack+0x10/0x14 show_stack from dump_stack_lvl+0x7c/0xac dump_stack_lvl from __lock_acquire+0x8e8/0x29dc __lock_acquire from lock_acquire+0x108/0x38c lock_acquire from __mutex_lock+0xb0/0xe78 __mutex_lock from mutex_lock_nested+0x1c/0x24 mutex_lock_nested from vsc85xx_txtstamp+0x50/0xac vsc85xx_txtstamp from lan966x_fdma_xmit+0xd8/0x3a8 lan966x_fdma_xmit from lan966x_port_xmit+0x1bc/0x350 lan966x_port_xmit from dev_hard_start_xmit+0xc8/0x2c0 dev_hard_start_xmit from sch_direct_xmit+0x8c/0x350 sch_direct_xmit from __dev_queue_xmit+0x680/0x1440 __dev_queue_xmit from packet_sendmsg+0xfa4/0x1568 packet_sendmsg from __sys_sendto+0x110/0x19c __sys_sendto from sys_send+0x18/0x20 sys_send from ret_fast_syscall+0x0/0x1c Exception stack(0xf0b05fa8 to 0xf0b05ff0) 5fa0: 00000001 0000000 0000000 0004b47a 0000003a 00000000 5fc0: 00000001 0000000 00000000 00000121 0004af58 00044874 00000000 00000000 5fe0: 00000001 bee9d420 00025a10 b6e75c7c So, instead of using the ts_lock for tx_queue, use the spinlock that skb_buff_head has. Reviewed-by: Vadim Fedorenko <vadim.fedorenko@linux.dev> Fixes: 7d272e6 ("net: phy: mscc: timestamping and PHC support") Signed-off-by: Horatiu Vultur <horatiu.vultur@microchip.com> Link: https://patch.msgid.link/20250902121259.3257536-1-horatiu.vultur@microchip.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
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The commit ced17ee ("Revert "virtio: reject shm region if length is zero"") exposes the following DAX page fault bug (this fix the failure that getting shm region alway returns false because of zero length): The commit 21aa65b ("mm: remove callers of pfn_t functionality") handles the DAX physical page address incorrectly: the removed macro 'phys_to_pfn_t()' should be replaced with 'PHYS_PFN()'. [ 1.390321] BUG: unable to handle page fault for address: ffffd3fb40000008 [ 1.390875] #PF: supervisor read access in kernel mode [ 1.391257] #PF: error_code(0x0000) - not-present page [ 1.391509] PGD 0 P4D 0 [ 1.391626] Oops: Oops: 0000 [#1] SMP NOPTI [ 1.391806] CPU: 6 UID: 1000 PID: 162 Comm: weston Not tainted 6.17.0-rc3-WSL2-STABLE #2 PREEMPT(none) [ 1.392361] RIP: 0010:dax_to_folio+0x14/0x60 [ 1.392653] Code: 52 c9 c3 00 66 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 0f 1f 44 00 00 48 c1 ef 05 48 c1 e7 06 48 03 3d 34 b5 31 01 <48> 8b 57 08 48 89 f8 f6 c2 01 75 2b 66 90 c3 cc cc cc cc f7 c7 ff [ 1.393727] RSP: 0000:ffffaf7d04407aa8 EFLAGS: 00010086 [ 1.394003] RAX: 000000a000000000 RBX: ffffaf7d04407bb0 RCX: 0000000000000000 [ 1.394524] RDX: ffffd17b40000008 RSI: 0000000000000083 RDI: ffffd3fb40000000 [ 1.394967] RBP: 0000000000000011 R08: 000000a000000000 R09: 0000000000000000 [ 1.395400] R10: 0000000000001000 R11: ffffaf7d04407c10 R12: 0000000000000000 [ 1.395806] R13: ffffa020557be9c0 R14: 0000014000000001 R15: 0000725970e94000 [ 1.396268] FS: 000072596d6d2ec0(0000) GS:ffffa0222dc59000(0000) knlGS:0000000000000000 [ 1.396715] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 1.397100] CR2: ffffd3fb40000008 CR3: 000000011579c005 CR4: 0000000000372ef0 [ 1.397518] Call Trace: [ 1.397663] <TASK> [ 1.397900] dax_insert_entry+0x13b/0x390 [ 1.398179] dax_fault_iter+0x2a5/0x6c0 [ 1.398443] dax_iomap_pte_fault+0x193/0x3c0 [ 1.398750] __fuse_dax_fault+0x8b/0x270 [ 1.398997] ? vm_mmap_pgoff+0x161/0x210 [ 1.399175] __do_fault+0x30/0x180 [ 1.399360] do_fault+0xc4/0x550 [ 1.399547] __handle_mm_fault+0x8e3/0xf50 [ 1.399731] ? do_syscall_64+0x72/0x1e0 [ 1.399958] handle_mm_fault+0x192/0x2f0 [ 1.400204] do_user_addr_fault+0x20e/0x700 [ 1.400418] exc_page_fault+0x66/0x150 [ 1.400602] asm_exc_page_fault+0x26/0x30 [ 1.400831] RIP: 0033:0x72596d1bf703 [ 1.401076] Code: 31 f6 45 31 e4 48 8d 15 b3 73 00 00 e8 06 03 00 00 8b 83 68 01 00 00 e9 8e fa ff ff 0f 1f 00 48 8b 44 24 08 4c 89 ee 48 89 df <c7> 00 21 43 34 12 e8 72 09 00 00 e9 6a fa ff ff 0f 1f 44 00 00 e8 [ 1.402172] RSP: 002b:00007ffc350f6dc0 EFLAGS: 00010202 [ 1.402488] RAX: 0000725970e94000 RBX: 00005b7c642c2560 RCX: 0000725970d359a7 [ 1.402898] RDX: 0000000000000003 RSI: 00007ffc350f6dc0 RDI: 00005b7c642c2560 [ 1.403284] RBP: 00007ffc350f6e90 R08: 000000000000000d R09: 0000000000000000 [ 1.403634] R10: 00007ffc350f6dd8 R11: 0000000000000246 R12: 0000000000000001 [ 1.404078] R13: 00007ffc350f6dc0 R14: 0000725970e29ce0 R15: 0000000000000003 [ 1.404450] </TASK> [ 1.404570] Modules linked in: [ 1.404821] CR2: ffffd3fb40000008 [ 1.405029] ---[ end trace 0000000000000000 ]--- [ 1.405323] RIP: 0010:dax_to_folio+0x14/0x60 [ 1.405556] Code: 52 c9 c3 00 66 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 0f 1f 44 00 00 48 c1 ef 05 48 c1 e7 06 48 03 3d 34 b5 31 01 <48> 8b 57 08 48 89 f8 f6 c2 01 75 2b 66 90 c3 cc cc cc cc f7 c7 ff [ 1.406639] RSP: 0000:ffffaf7d04407aa8 EFLAGS: 00010086 [ 1.406910] RAX: 000000a000000000 RBX: ffffaf7d04407bb0 RCX: 0000000000000000 [ 1.407379] RDX: ffffd17b40000008 RSI: 0000000000000083 RDI: ffffd3fb40000000 [ 1.407800] RBP: 0000000000000011 R08: 000000a000000000 R09: 0000000000000000 [ 1.408246] R10: 0000000000001000 R11: ffffaf7d04407c10 R12: 0000000000000000 [ 1.408666] R13: ffffa020557be9c0 R14: 0000014000000001 R15: 0000725970e94000 [ 1.409170] FS: 000072596d6d2ec0(0000) GS:ffffa0222dc59000(0000) knlGS:0000000000000000 [ 1.409608] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 1.409977] CR2: ffffd3fb40000008 CR3: 000000011579c005 CR4: 0000000000372ef0 [ 1.410437] Kernel panic - not syncing: Fatal exception [ 1.410857] Kernel Offset: 0xc000000 from 0xffffffff81000000 (relocation range: 0xffffffff80000000-0xffffffffbfffffff) Fixes: 21aa65b ("mm: remove callers of pfn_t functionality") Signed-off-by: Haiyue Wang <haiyuewa@163.com> Link: https://lore.kernel.org/20250904120339.972-1-haiyuewa@163.com Acked-by: David Hildenbrand <david@redhat.com> Reviewed-by: Miklos Szeredi <mszeredi@redhat.com> Signed-off-by: Christian Brauner <brauner@kernel.org>
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Problem description
===================
Lockdep reports a possible circular locking dependency (AB/BA) between
&pl->state_mutex and &phy->lock, as follows.
phylink_resolve() // acquires &pl->state_mutex
-> phylink_major_config()
-> phy_config_inband() // acquires &pl->phydev->lock
whereas all the other call sites where &pl->state_mutex and
&pl->phydev->lock have the locking scheme reversed. Everywhere else,
&pl->phydev->lock is acquired at the top level, and &pl->state_mutex at
the lower level. A clear example is phylink_bringup_phy().
The outlier is the newly introduced phy_config_inband() and the existing
lock order is the correct one. To understand why it cannot be the other
way around, it is sufficient to consider phylink_phy_change(), phylink's
callback from the PHY device's phy->phy_link_change() virtual method,
invoked by the PHY state machine.
phy_link_up() and phy_link_down(), the (indirect) callers of
phylink_phy_change(), are called with &phydev->lock acquired.
Then phylink_phy_change() acquires its own &pl->state_mutex, to
serialize changes made to its pl->phy_state and pl->link_config.
So all other instances of &pl->state_mutex and &phydev->lock must be
consistent with this order.
Problem impact
==============
I think the kernel runs a serious deadlock risk if an existing
phylink_resolve() thread, which results in a phy_config_inband() call,
is concurrent with a phy_link_up() or phy_link_down() call, which will
deadlock on &pl->state_mutex in phylink_phy_change(). Practically
speaking, the impact may be limited by the slow speed of the medium
auto-negotiation protocol, which makes it unlikely for the current state
to still be unresolved when a new one is detected, but I think the
problem is there. Nonetheless, the problem was discovered using lockdep.
Proposed solution
=================
Practically speaking, the phy_config_inband() requirement of having
phydev->lock acquired must transfer to the caller (phylink is the only
caller). There, it must bubble up until immediately before
&pl->state_mutex is acquired, for the cases where that takes place.
Solution details, considerations, notes
=======================================
This is the phy_config_inband() call graph:
sfp_upstream_ops :: connect_phy()
|
v
phylink_sfp_connect_phy()
|
v
phylink_sfp_config_phy()
|
| sfp_upstream_ops :: module_insert()
| |
| v
| phylink_sfp_module_insert()
| |
| | sfp_upstream_ops :: module_start()
| | |
| | v
| | phylink_sfp_module_start()
| | |
| v v
| phylink_sfp_config_optical()
phylink_start() | |
| phylink_resume() v v
| | phylink_sfp_set_config()
| | |
v v v
phylink_mac_initial_config()
| phylink_resolve()
| | phylink_ethtool_ksettings_set()
v v v
phylink_major_config()
|
v
phy_config_inband()
phylink_major_config() caller #1, phylink_mac_initial_config(), does not
acquire &pl->state_mutex nor do its callers. It must acquire
&pl->phydev->lock prior to calling phylink_major_config().
phylink_major_config() caller #2, phylink_resolve() acquires
&pl->state_mutex, thus also needs to acquire &pl->phydev->lock.
phylink_major_config() caller #3, phylink_ethtool_ksettings_set(), is
completely uninteresting, because it only calls phylink_major_config()
if pl->phydev is NULL (otherwise it calls phy_ethtool_ksettings_set()).
We need to change nothing there.
Other solutions
===============
The lock inversion between &pl->state_mutex and &pl->phydev->lock has
occurred at least once before, as seen in commit c718af2 ("net:
phylink: fix ethtool -A with attached PHYs"). The solution there was to
simply not call phy_set_asym_pause() under the &pl->state_mutex. That
cannot be extended to our case though, where the phy_config_inband()
call is much deeper inside the &pl->state_mutex section.
Fixes: 5fd0f1a ("net: phylink: add negotiation of in-band capabilities")
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Reviewed-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>
Link: https://patch.msgid.link/20250904125238.193990-2-vladimir.oltean@nxp.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
johnhubbard
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Sep 30, 2025
5da3d94 ("PCI: mvebu: Use for_each_of_range() iterator for parsing "ranges"") simplified code by using the for_each_of_range() iterator, but it broke PCI enumeration on Turris Omnia (and probably other mvebu targets). Issue #1: To determine range.flags, of_pci_range_parser_one() uses bus->get_flags(), which resolves to of_bus_pci_get_flags(), which already returns an IORESOURCE bit field, and NOT the original flags from the "ranges" resource. Then mvebu_get_tgt_attr() attempts the very same conversion again. Remove the misinterpretation of range.flags in mvebu_get_tgt_attr(), to restore the intended behavior. Issue #2: The driver needs target and attributes, which are encoded in the raw address values of the "/soc/pcie/ranges" resource. According to of_pci_range_parser_one(), the raw values are stored in range.bus_addr and range.parent_bus_addr, respectively. range.cpu_addr is a translated version of range.parent_bus_addr, and not relevant here. Use the correct range structure member, to extract target and attributes. This restores the intended behavior. Fixes: 5da3d94 ("PCI: mvebu: Use for_each_of_range() iterator for parsing "ranges"") Reported-by: Jan Palus <jpalus@fastmail.com> Closes: https://bugzilla.kernel.org/show_bug.cgi?id=220479 Signed-off-by: Klaus Kudielka <klaus.kudielka@gmail.com> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com> Tested-by: Tony Dinh <mibodhi@gmail.com> Tested-by: Jan Palus <jpalus@fastmail.com> Link: https://patch.msgid.link/20250907102303.29735-1-klaus.kudielka@gmail.com
johnhubbard
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Oct 24, 2025
Since blamed commit, unregister_netdevice_many_notify() takes the netdev
mutex if the device needs it.
If the device list is too long, this will lock more device mutexes than
lockdep can handle:
unshare -n \
bash -c 'for i in $(seq 1 100);do ip link add foo$i type dummy;done'
BUG: MAX_LOCK_DEPTH too low!
turning off the locking correctness validator.
depth: 48 max: 48!
48 locks held by kworker/u16:1/69:
#0: ..148 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work
#1: ..d40 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work
#2: ..bd0 (pernet_ops_rwsem){++++}-{4:4}, at: cleanup_net
#3: ..aa8 (rtnl_mutex){+.+.}-{4:4}, at: default_device_exit_batch
#4: ..cb0 (&dev_instance_lock_key#3){+.+.}-{4:4}, at: unregister_netdevice_many_notify
[..]
Add a helper to close and then unlock a list of net_devices.
Devices that are not up have to be skipped - netif_close_many always
removes them from the list without any other actions taken, so they'd
remain in locked state.
Close devices whenever we've used up half of the tracking slots or we
processed entire list without hitting the limit.
Fixes: 7e4d784 ("net: hold netdev instance lock during rtnetlink operations")
Signed-off-by: Florian Westphal <fw@strlen.de>
Link: https://patch.msgid.link/20251013185052.14021-1-fw@strlen.de
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
johnhubbard
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Oct 24, 2025
Expand the prefault memory selftest to add a regression test for a KVM bug where KVM's retry logic would result in (breakable) deadlock due to the memslot deletion waiting on prefaulting to release SRCU, and prefaulting waiting on the memslot to fully disappear (KVM uses a two-step process to delete memslots, and KVM x86 retries page faults if a to-be-deleted, a.k.a. INVALID, memslot is encountered). To exercise concurrent memslot remove, spawn a second thread to initiate memslot removal at roughly the same time as prefaulting. Test memslot removal for all testcases, i.e. don't limit concurrent removal to only the success case. There are essentially three prefault scenarios (so far) that are of interest: 1. Success 2. ENOENT due to no memslot 3. EAGAIN due to INVALID memslot For all intents and purposes, #1 and #2 are mutually exclusive, or rather, easier to test via separate testcases since writing to non-existent memory is trivial. But for #3, making it mutually exclusive with #1 _or_ #2 is actually more complex than testing memslot removal for all scenarios. The only requirement to let memslot removal coexist with other scenarios is a way to guarantee a stable result, e.g. that the "no memslot" test observes ENOENT, not EAGAIN, for the final checks. So, rather than make memslot removal mutually exclusive with the ENOENT scenario, simply restore the memslot and retry prefaulting. For the "no memslot" case, KVM_PRE_FAULT_MEMORY should be idempotent, i.e. should always fail with ENOENT regardless of how many times userspace attempts prefaulting. Pass in both the base GPA and the offset (instead of the "full" GPA) so that the worker can recreate the memslot. Signed-off-by: Yan Zhao <yan.y.zhao@intel.com> Co-developed-by: Sean Christopherson <seanjc@google.com> Link: https://lore.kernel.org/r/20250924174255.2141847-1-seanjc@google.com Signed-off-by: Sean Christopherson <seanjc@google.com>
ttabi
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to ttabi/linux
that referenced
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Oct 28, 2025
The original code causes a circular locking dependency found by lockdep. ====================================================== WARNING: possible circular locking dependency detected 6.16.0-rc6-lgci-xe-xe-pw-151626v3+ johnhubbard#1 Tainted: G S U ------------------------------------------------------ xe_fault_inject/5091 is trying to acquire lock: ffff888156815688 ((work_completion)(&(&devcd->del_wk)->work)){+.+.}-{0:0}, at: __flush_work+0x25d/0x660 but task is already holding lock: ffff888156815620 (&devcd->mutex){+.+.}-{3:3}, at: dev_coredump_put+0x3f/0xa0 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> johnhubbard#2 (&devcd->mutex){+.+.}-{3:3}: mutex_lock_nested+0x4e/0xc0 devcd_data_write+0x27/0x90 sysfs_kf_bin_write+0x80/0xf0 kernfs_fop_write_iter+0x169/0x220 vfs_write+0x293/0x560 ksys_write+0x72/0xf0 __x64_sys_write+0x19/0x30 x64_sys_call+0x2bf/0x2660 do_syscall_64+0x93/0xb60 entry_SYSCALL_64_after_hwframe+0x76/0x7e -> johnhubbard#1 (kn->active#236){++++}-{0:0}: kernfs_drain+0x1e2/0x200 __kernfs_remove+0xae/0x400 kernfs_remove_by_name_ns+0x5d/0xc0 remove_files+0x54/0x70 sysfs_remove_group+0x3d/0xa0 sysfs_remove_groups+0x2e/0x60 device_remove_attrs+0xc7/0x100 device_del+0x15d/0x3b0 devcd_del+0x19/0x30 process_one_work+0x22b/0x6f0 worker_thread+0x1e8/0x3d0 kthread+0x11c/0x250 ret_from_fork+0x26c/0x2e0 ret_from_fork_asm+0x1a/0x30 -> #0 ((work_completion)(&(&devcd->del_wk)->work)){+.+.}-{0:0}: __lock_acquire+0x1661/0x2860 lock_acquire+0xc4/0x2f0 __flush_work+0x27a/0x660 flush_delayed_work+0x5d/0xa0 dev_coredump_put+0x63/0xa0 xe_driver_devcoredump_fini+0x12/0x20 [xe] devm_action_release+0x12/0x30 release_nodes+0x3a/0x120 devres_release_all+0x8a/0xd0 device_unbind_cleanup+0x12/0x80 device_release_driver_internal+0x23a/0x280 device_driver_detach+0x14/0x20 unbind_store+0xaf/0xc0 drv_attr_store+0x21/0x50 sysfs_kf_write+0x4a/0x80 kernfs_fop_write_iter+0x169/0x220 vfs_write+0x293/0x560 ksys_write+0x72/0xf0 __x64_sys_write+0x19/0x30 x64_sys_call+0x2bf/0x2660 do_syscall_64+0x93/0xb60 entry_SYSCALL_64_after_hwframe+0x76/0x7e other info that might help us debug this: Chain exists of: (work_completion)(&(&devcd->del_wk)->work) --> kn->active#236 --> &devcd->mutex Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(&devcd->mutex); lock(kn->active#236); lock(&devcd->mutex); lock((work_completion)(&(&devcd->del_wk)->work)); *** DEADLOCK *** 5 locks held by xe_fault_inject/5091: #0: ffff8881129f9488 (sb_writers#5){.+.+}-{0:0}, at: ksys_write+0x72/0xf0 johnhubbard#1: ffff88810c755078 (&of->mutex#2){+.+.}-{3:3}, at: kernfs_fop_write_iter+0x123/0x220 johnhubbard#2: ffff8881054811a0 (&dev->mutex){....}-{3:3}, at: device_release_driver_internal+0x55/0x280 #3: ffff888156815620 (&devcd->mutex){+.+.}-{3:3}, at: dev_coredump_put+0x3f/0xa0 #4: ffffffff8359e020 (rcu_read_lock){....}-{1:2}, at: __flush_work+0x72/0x660 stack backtrace: CPU: 14 UID: 0 PID: 5091 Comm: xe_fault_inject Tainted: G S U 6.16.0-rc6-lgci-xe-xe-pw-151626v3+ johnhubbard#1 PREEMPT_{RT,(lazy)} Tainted: [S]=CPU_OUT_OF_SPEC, [U]=USER Hardware name: Micro-Star International Co., Ltd. MS-7D25/PRO Z690-A DDR4(MS-7D25), BIOS 1.10 12/13/2021 Call Trace: <TASK> dump_stack_lvl+0x91/0xf0 dump_stack+0x10/0x20 print_circular_bug+0x285/0x360 check_noncircular+0x135/0x150 ? register_lock_class+0x48/0x4a0 __lock_acquire+0x1661/0x2860 lock_acquire+0xc4/0x2f0 ? __flush_work+0x25d/0x660 ? mark_held_locks+0x46/0x90 ? __flush_work+0x25d/0x660 __flush_work+0x27a/0x660 ? __flush_work+0x25d/0x660 ? trace_hardirqs_on+0x1e/0xd0 ? __pfx_wq_barrier_func+0x10/0x10 flush_delayed_work+0x5d/0xa0 dev_coredump_put+0x63/0xa0 xe_driver_devcoredump_fini+0x12/0x20 [xe] devm_action_release+0x12/0x30 release_nodes+0x3a/0x120 devres_release_all+0x8a/0xd0 device_unbind_cleanup+0x12/0x80 device_release_driver_internal+0x23a/0x280 ? bus_find_device+0xa8/0xe0 device_driver_detach+0x14/0x20 unbind_store+0xaf/0xc0 drv_attr_store+0x21/0x50 sysfs_kf_write+0x4a/0x80 kernfs_fop_write_iter+0x169/0x220 vfs_write+0x293/0x560 ksys_write+0x72/0xf0 __x64_sys_write+0x19/0x30 x64_sys_call+0x2bf/0x2660 do_syscall_64+0x93/0xb60 ? __f_unlock_pos+0x15/0x20 ? __x64_sys_getdents64+0x9b/0x130 ? __pfx_filldir64+0x10/0x10 ? do_syscall_64+0x1a2/0xb60 ? clear_bhb_loop+0x30/0x80 ? clear_bhb_loop+0x30/0x80 entry_SYSCALL_64_after_hwframe+0x76/0x7e RIP: 0033:0x76e292edd574 Code: c7 00 16 00 00 00 b8 ff ff ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 f3 0f 1e fa 80 3d d5 ea 0e 00 00 74 13 b8 01 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 54 c3 0f 1f 00 55 48 89 e5 48 83 ec 20 48 89 RSP: 002b:00007fffe247a828 EFLAGS: 00000202 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 000076e292edd574 RDX: 000000000000000c RSI: 00006267f6306063 RDI: 000000000000000b RBP: 000000000000000c R08: 000076e292fc4b20 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000202 R12: 00006267f6306063 R13: 000000000000000b R14: 00006267e6859c00 R15: 000076e29322a000 </TASK> xe 0000:03:00.0: [drm] Xe device coredump has been deleted. Fixes: 01daccf ("devcoredump : Serialize devcd_del work") Cc: Mukesh Ojha <quic_mojha@quicinc.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Johannes Berg <johannes@sipsolutions.net> Cc: Rafael J. Wysocki <rafael@kernel.org> Cc: Danilo Krummrich <dakr@kernel.org> Cc: linux-kernel@vger.kernel.org Cc: stable@vger.kernel.org # v6.1+ Signed-off-by: Maarten Lankhorst <dev@lankhorst.se> Cc: Matthew Brost <matthew.brost@intel.com> Acked-by: Mukesh Ojha <mukesh.ojha@oss.qualcomm.com> Link: https://lore.kernel.org/r/20250723142416.1020423-1-dev@lankhorst.se Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
johnhubbard
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Nov 21, 2025
When a connector is connected but inactive (e.g., disabled by desktop environments), pipe_ctx->stream_res.tg will be destroyed. Then, reading odm_combine_segments causes kernel NULL pointer dereference. 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: 16 UID: 0 PID: 26474 Comm: cat Not tainted 6.17.0+ #2 PREEMPT(lazy) e6a17af9ee6db7c63e9d90dbe5b28ccab67520c6 Hardware name: LENOVO 21Q4/LNVNB161216, BIOS PXCN25WW 03/27/2025 RIP: 0010:odm_combine_segments_show+0x93/0xf0 [amdgpu] Code: 41 83 b8 b0 00 00 00 01 75 6e 48 98 ba a1 ff ff ff 48 c1 e0 0c 48 8d 8c 07 d8 02 00 00 48 85 c9 74 2d 48 8b bc 07 f0 08 00 00 <48> 8b 07 48 8b 80 08 02 00> RSP: 0018:ffffd1bf4b953c58 EFLAGS: 00010286 RAX: 0000000000005000 RBX: ffff8e35976b02d0 RCX: ffff8e3aeed052d8 RDX: 00000000ffffffa1 RSI: ffff8e35a3120800 RDI: 0000000000000000 RBP: 0000000000000000 R08: ffff8e3580eb0000 R09: ffff8e35976b02d0 R10: ffffd1bf4b953c78 R11: 0000000000000000 R12: ffffd1bf4b953d08 R13: 0000000000040000 R14: 0000000000000001 R15: 0000000000000001 FS: 00007f44d3f9f740(0000) GS:ffff8e3caa47f000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000000000000 CR3: 00000006485c2000 CR4: 0000000000f50ef0 PKRU: 55555554 Call Trace: <TASK> seq_read_iter+0x125/0x490 ? __alloc_frozen_pages_noprof+0x18f/0x350 seq_read+0x12c/0x170 full_proxy_read+0x51/0x80 vfs_read+0xbc/0x390 ? __handle_mm_fault+0xa46/0xef0 ? do_syscall_64+0x71/0x900 ksys_read+0x73/0xf0 do_syscall_64+0x71/0x900 ? count_memcg_events+0xc2/0x190 ? handle_mm_fault+0x1d7/0x2d0 ? do_user_addr_fault+0x21a/0x690 ? exc_page_fault+0x7e/0x1a0 entry_SYSCALL_64_after_hwframe+0x6c/0x74 RIP: 0033:0x7f44d4031687 Code: 48 89 fa 4c 89 df e8 58 b3 00 00 8b 93 08 03 00 00 59 5e 48 83 f8 fc 74 1a 5b c3 0f 1f 84 00 00 00 00 00 48 8b 44 24 10 0f 05 <5b> c3 0f 1f 80 00 00 00 00> RSP: 002b:00007ffdb4b5f0b0 EFLAGS: 00000202 ORIG_RAX: 0000000000000000 RAX: ffffffffffffffda RBX: 00007f44d3f9f740 RCX: 00007f44d4031687 RDX: 0000000000040000 RSI: 00007f44d3f5e000 RDI: 0000000000000003 RBP: 0000000000040000 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000202 R12: 00007f44d3f5e000 R13: 0000000000000003 R14: 0000000000000000 R15: 0000000000040000 </TASK> Modules linked in: tls tcp_diag inet_diag xt_mark ccm snd_hrtimer snd_seq_dummy snd_seq_midi snd_seq_oss snd_seq_midi_event snd_rawmidi snd_seq snd_seq_device x> snd_hda_codec_atihdmi snd_hda_codec_realtek_lib lenovo_wmi_helpers think_lmi snd_hda_codec_generic snd_hda_codec_hdmi snd_soc_core kvm snd_compress uvcvideo sn> platform_profile joydev amd_pmc mousedev mac_hid sch_fq_codel uinput i2c_dev parport_pc ppdev lp parport nvme_fabrics loop nfnetlink ip_tables x_tables dm_cryp> CR2: 0000000000000000 ---[ end trace 0000000000000000 ]--- RIP: 0010:odm_combine_segments_show+0x93/0xf0 [amdgpu] Code: 41 83 b8 b0 00 00 00 01 75 6e 48 98 ba a1 ff ff ff 48 c1 e0 0c 48 8d 8c 07 d8 02 00 00 48 85 c9 74 2d 48 8b bc 07 f0 08 00 00 <48> 8b 07 48 8b 80 08 02 00> RSP: 0018:ffffd1bf4b953c58 EFLAGS: 00010286 RAX: 0000000000005000 RBX: ffff8e35976b02d0 RCX: ffff8e3aeed052d8 RDX: 00000000ffffffa1 RSI: ffff8e35a3120800 RDI: 0000000000000000 RBP: 0000000000000000 R08: ffff8e3580eb0000 R09: ffff8e35976b02d0 R10: ffffd1bf4b953c78 R11: 0000000000000000 R12: ffffd1bf4b953d08 R13: 0000000000040000 R14: 0000000000000001 R15: 0000000000000001 FS: 00007f44d3f9f740(0000) GS:ffff8e3caa47f000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000000000000 CR3: 00000006485c2000 CR4: 0000000000f50ef0 PKRU: 55555554 Fix this by checking pipe_ctx->stream_res.tg before dereferencing. Fixes: 07926ba ("drm/amd/display: Add debugfs interface for ODM combine info") Signed-off-by: Rong Zhang <i@rong.moe> Reviewed-by: Mario Limoncello <mario.limonciello@amd.com> Signed-off-by: Mario Limonciello <mario.limonciello@amd.com> Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
johnhubbard
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Nov 21, 2025
…rg/drm/i915/kernel into drm-next drm/i915 feature pull #2 for v6.19: Features and functionality: - Add initial display support for Xe3p_LPD, display version 35 (Sai Teja, Matt R, Gustavo, Matt A, Ankit, Juha-pekka, Luca, Ravi Kumar) - Compute LT PHY HDMI params when port clock not in predefined tables (Suraj) Refactoring and cleanups: - Refactor intel_frontbuffer split between i915, xe, and display (Ville) - Clean up intel_de_wait_custom() usage (Ville) - Unify display register polling interfaces (Ville) - Finish removal of the expensive format info lookups (Ville) - Cursor code cleanups (Ville) - Convert intel_rom interfaces to struct drm_device (Jani) Fixes: - Fix uninitialized variable in DSI exec packet (Jonathan) - Fix PIPEDMC logging (Alok Tiwari) - Fix PSR pipe to vblank conversion (Jani) - Fix intel_frontbuffer lifetime handling (Ville) - Disable Panel Replay on DP MST for the time being (Imre) Merges: - Backmerge drm-next to get the drm_print.h changes (Jani) Signed-off-by: Dave Airlie <airlied@redhat.com> From: Jani Nikula <jani.nikula@intel.com> Link: https://patch.msgid.link/b131309bb7310ab749f1770aa6e36fa8d6a82fa5@intel.com
johnhubbard
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Nov 21, 2025
On completion of i915_vma_pin_ww(), a synchronous variant of dma_fence_work_commit() is called. When pinning a VMA to GGTT address space on a Cherry View family processor, or on a Broxton generation SoC with VTD enabled, i.e., when stop_machine() is then called from intel_ggtt_bind_vma(), that can potentially lead to lock inversion among reservation_ww and cpu_hotplug locks. [86.861179] ====================================================== [86.861193] WARNING: possible circular locking dependency detected [86.861209] 6.15.0-rc5-CI_DRM_16515-gca0305cadc2d+ #1 Tainted: G U [86.861226] ------------------------------------------------------ [86.861238] i915_module_loa/1432 is trying to acquire lock: [86.861252] ffffffff83489090 (cpu_hotplug_lock){++++}-{0:0}, at: stop_machine+0x1c/0x50 [86.861290] but task is already holding lock: [86.861303] ffffc90002e0b4c8 (reservation_ww_class_mutex){+.+.}-{3:3}, at: i915_vma_pin.constprop.0+0x39/0x1d0 [i915] [86.862233] which lock already depends on the new lock. [86.862251] the existing dependency chain (in reverse order) is: [86.862265] -> #5 (reservation_ww_class_mutex){+.+.}-{3:3}: [86.862292] dma_resv_lockdep+0x19a/0x390 [86.862315] do_one_initcall+0x60/0x3f0 [86.862334] kernel_init_freeable+0x3cd/0x680 [86.862353] kernel_init+0x1b/0x200 [86.862369] ret_from_fork+0x47/0x70 [86.862383] ret_from_fork_asm+0x1a/0x30 [86.862399] -> #4 (reservation_ww_class_acquire){+.+.}-{0:0}: [86.862425] dma_resv_lockdep+0x178/0x390 [86.862440] do_one_initcall+0x60/0x3f0 [86.862454] kernel_init_freeable+0x3cd/0x680 [86.862470] kernel_init+0x1b/0x200 [86.862482] ret_from_fork+0x47/0x70 [86.862495] ret_from_fork_asm+0x1a/0x30 [86.862509] -> #3 (&mm->mmap_lock){++++}-{3:3}: [86.862531] down_read_killable+0x46/0x1e0 [86.862546] lock_mm_and_find_vma+0xa2/0x280 [86.862561] do_user_addr_fault+0x266/0x8e0 [86.862578] exc_page_fault+0x8a/0x2f0 [86.862593] asm_exc_page_fault+0x27/0x30 [86.862607] filldir64+0xeb/0x180 [86.862620] kernfs_fop_readdir+0x118/0x480 [86.862635] iterate_dir+0xcf/0x2b0 [86.862648] __x64_sys_getdents64+0x84/0x140 [86.862661] x64_sys_call+0x1058/0x2660 [86.862675] do_syscall_64+0x91/0xe90 [86.862689] entry_SYSCALL_64_after_hwframe+0x76/0x7e [86.862703] -> #2 (&root->kernfs_rwsem){++++}-{3:3}: [86.862725] down_write+0x3e/0xf0 [86.862738] kernfs_add_one+0x30/0x3c0 [86.862751] kernfs_create_dir_ns+0x53/0xb0 [86.862765] internal_create_group+0x134/0x4c0 [86.862779] sysfs_create_group+0x13/0x20 [86.862792] topology_add_dev+0x1d/0x30 [86.862806] cpuhp_invoke_callback+0x4b5/0x850 [86.862822] cpuhp_issue_call+0xbf/0x1f0 [86.862836] __cpuhp_setup_state_cpuslocked+0x111/0x320 [86.862852] __cpuhp_setup_state+0xb0/0x220 [86.862866] topology_sysfs_init+0x30/0x50 [86.862879] do_one_initcall+0x60/0x3f0 [86.862893] kernel_init_freeable+0x3cd/0x680 [86.862908] kernel_init+0x1b/0x200 [86.862921] ret_from_fork+0x47/0x70 [86.862934] ret_from_fork_asm+0x1a/0x30 [86.862947] -> #1 (cpuhp_state_mutex){+.+.}-{3:3}: [86.862969] __mutex_lock+0xaa/0xed0 [86.862982] mutex_lock_nested+0x1b/0x30 [86.862995] __cpuhp_setup_state_cpuslocked+0x67/0x320 [86.863012] __cpuhp_setup_state+0xb0/0x220 [86.863026] page_alloc_init_cpuhp+0x2d/0x60 [86.863041] mm_core_init+0x22/0x2d0 [86.863054] start_kernel+0x576/0xbd0 [86.863068] x86_64_start_reservations+0x18/0x30 [86.863084] x86_64_start_kernel+0xbf/0x110 [86.863098] common_startup_64+0x13e/0x141 [86.863114] -> #0 (cpu_hotplug_lock){++++}-{0:0}: [86.863135] __lock_acquire+0x1635/0x2810 [86.863152] lock_acquire+0xc4/0x2f0 [86.863166] cpus_read_lock+0x41/0x100 [86.863180] stop_machine+0x1c/0x50 [86.863194] bxt_vtd_ggtt_insert_entries__BKL+0x3b/0x60 [i915] [86.863987] intel_ggtt_bind_vma+0x43/0x70 [i915] [86.864735] __vma_bind+0x55/0x70 [i915] [86.865510] fence_work+0x26/0xa0 [i915] [86.866248] fence_notify+0xa1/0x140 [i915] [86.866983] __i915_sw_fence_complete+0x8f/0x270 [i915] [86.867719] i915_sw_fence_commit+0x39/0x60 [i915] [86.868453] i915_vma_pin_ww+0x462/0x1360 [i915] [86.869228] i915_vma_pin.constprop.0+0x133/0x1d0 [i915] [86.870001] initial_plane_vma+0x307/0x840 [i915] [86.870774] intel_initial_plane_config+0x33f/0x670 [i915] [86.871546] intel_display_driver_probe_nogem+0x1c6/0x260 [i915] [86.872330] i915_driver_probe+0x7fa/0xe80 [i915] [86.873057] i915_pci_probe+0xe6/0x220 [i915] [86.873782] local_pci_probe+0x47/0xb0 [86.873802] pci_device_probe+0xf3/0x260 [86.873817] really_probe+0xf1/0x3c0 [86.873833] __driver_probe_device+0x8c/0x180 [86.873848] driver_probe_device+0x24/0xd0 [86.873862] __driver_attach+0x10f/0x220 [86.873876] bus_for_each_dev+0x7f/0xe0 [86.873892] driver_attach+0x1e/0x30 [86.873904] bus_add_driver+0x151/0x290 [86.873917] driver_register+0x5e/0x130 [86.873931] __pci_register_driver+0x7d/0x90 [86.873945] i915_pci_register_driver+0x23/0x30 [i915] [86.874678] i915_init+0x37/0x120 [i915] [86.875347] do_one_initcall+0x60/0x3f0 [86.875369] do_init_module+0x97/0x2a0 [86.875385] load_module+0x2c54/0x2d80 [86.875398] init_module_from_file+0x96/0xe0 [86.875413] idempotent_init_module+0x117/0x330 [86.875426] __x64_sys_finit_module+0x77/0x100 [86.875440] x64_sys_call+0x24de/0x2660 [86.875454] do_syscall_64+0x91/0xe90 [86.875470] entry_SYSCALL_64_after_hwframe+0x76/0x7e [86.875486] other info that might help us debug this: [86.875502] Chain exists of: cpu_hotplug_lock --> reservation_ww_class_acquire --> reservation_ww_class_mutex [86.875539] Possible unsafe locking scenario: [86.875552] CPU0 CPU1 [86.875563] ---- ---- [86.875573] lock(reservation_ww_class_mutex); [86.875588] lock(reservation_ww_class_acquire); [86.875606] lock(reservation_ww_class_mutex); [86.875624] rlock(cpu_hotplug_lock); [86.875637] *** DEADLOCK *** [86.875650] 3 locks held by i915_module_loa/1432: [86.875663] #0: ffff888101f5c1b0 (&dev->mutex){....}-{3:3}, at: __driver_attach+0x104/0x220 [86.875699] #1: ffffc90002e0b4a0 (reservation_ww_class_acquire){+.+.}-{0:0}, at: i915_vma_pin.constprop.0+0x39/0x1d0 [i915] [86.876512] #2: ffffc90002e0b4c8 (reservation_ww_class_mutex){+.+.}-{3:3}, at: i915_vma_pin.constprop.0+0x39/0x1d0 [i915] [86.877305] stack backtrace: [86.877326] CPU: 0 UID: 0 PID: 1432 Comm: i915_module_loa Tainted: G U 6.15.0-rc5-CI_DRM_16515-gca0305cadc2d+ #1 PREEMPT(voluntary) [86.877334] Tainted: [U]=USER [86.877336] Hardware name: /NUC5CPYB, BIOS PYBSWCEL.86A.0079.2020.0420.1316 04/20/2020 [86.877339] Call Trace: [86.877344] <TASK> [86.877353] dump_stack_lvl+0x91/0xf0 [86.877364] dump_stack+0x10/0x20 [86.877369] print_circular_bug+0x285/0x360 [86.877379] check_noncircular+0x135/0x150 [86.877390] __lock_acquire+0x1635/0x2810 [86.877403] lock_acquire+0xc4/0x2f0 [86.877408] ? stop_machine+0x1c/0x50 [86.877422] ? __pfx_bxt_vtd_ggtt_insert_entries__cb+0x10/0x10 [i915] [86.878173] cpus_read_lock+0x41/0x100 [86.878182] ? stop_machine+0x1c/0x50 [86.878191] ? __pfx_bxt_vtd_ggtt_insert_entries__cb+0x10/0x10 [i915] [86.878916] stop_machine+0x1c/0x50 [86.878927] bxt_vtd_ggtt_insert_entries__BKL+0x3b/0x60 [i915] [86.879652] intel_ggtt_bind_vma+0x43/0x70 [i915] [86.880375] __vma_bind+0x55/0x70 [i915] [86.881133] fence_work+0x26/0xa0 [i915] [86.881851] fence_notify+0xa1/0x140 [i915] [86.882566] __i915_sw_fence_complete+0x8f/0x270 [i915] [86.883286] i915_sw_fence_commit+0x39/0x60 [i915] [86.884003] i915_vma_pin_ww+0x462/0x1360 [i915] [86.884756] ? i915_vma_pin.constprop.0+0x6c/0x1d0 [i915] [86.885513] i915_vma_pin.constprop.0+0x133/0x1d0 [i915] [86.886281] initial_plane_vma+0x307/0x840 [i915] [86.887049] intel_initial_plane_config+0x33f/0x670 [i915] [86.887819] intel_display_driver_probe_nogem+0x1c6/0x260 [i915] [86.888587] i915_driver_probe+0x7fa/0xe80 [i915] [86.889293] ? mutex_unlock+0x12/0x20 [86.889301] ? drm_privacy_screen_get+0x171/0x190 [86.889308] ? acpi_dev_found+0x66/0x80 [86.889321] i915_pci_probe+0xe6/0x220 [i915] [86.890038] local_pci_probe+0x47/0xb0 [86.890049] pci_device_probe+0xf3/0x260 [86.890058] really_probe+0xf1/0x3c0 [86.890067] __driver_probe_device+0x8c/0x180 [86.890072] driver_probe_device+0x24/0xd0 [86.890078] __driver_attach+0x10f/0x220 [86.890083] ? __pfx___driver_attach+0x10/0x10 [86.890088] bus_for_each_dev+0x7f/0xe0 [86.890097] driver_attach+0x1e/0x30 [86.890101] bus_add_driver+0x151/0x290 [86.890107] driver_register+0x5e/0x130 [86.890113] __pci_register_driver+0x7d/0x90 [86.890119] i915_pci_register_driver+0x23/0x30 [i915] [86.890833] i915_init+0x37/0x120 [i915] [86.891482] ? __pfx_i915_init+0x10/0x10 [i915] [86.892135] do_one_initcall+0x60/0x3f0 [86.892145] ? __kmalloc_cache_noprof+0x33f/0x470 [86.892157] do_init_module+0x97/0x2a0 [86.892164] load_module+0x2c54/0x2d80 [86.892168] ? __kernel_read+0x15c/0x300 [86.892185] ? kernel_read_file+0x2b1/0x320 [86.892195] init_module_from_file+0x96/0xe0 [86.892199] ? init_module_from_file+0x96/0xe0 [86.892211] idempotent_init_module+0x117/0x330 [86.892224] __x64_sys_finit_module+0x77/0x100 [86.892230] x64_sys_call+0x24de/0x2660 [86.892236] do_syscall_64+0x91/0xe90 [86.892243] ? irqentry_exit+0x77/0xb0 [86.892249] ? sysvec_apic_timer_interrupt+0x57/0xc0 [86.892256] entry_SYSCALL_64_after_hwframe+0x76/0x7e [86.892261] RIP: 0033:0x7303e1b2725d [86.892271] Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 90 f3 0f 1e fa 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 8b 0d 8b bb 0d 00 f7 d8 64 89 01 48 [86.892276] RSP: 002b:00007ffddd1fdb38 EFLAGS: 00000246 ORIG_RAX: 0000000000000139 [86.892281] RAX: ffffffffffffffda RBX: 00005d771d88fd90 RCX: 00007303e1b2725d [86.892285] RDX: 0000000000000000 RSI: 00005d771d893aa0 RDI: 000000000000000c [86.892287] RBP: 00007ffddd1fdbf0 R08: 0000000000000040 R09: 00007ffddd1fdb80 [86.892289] R10: 00007303e1c03b20 R11: 0000000000000246 R12: 00005d771d893aa0 [86.892292] R13: 0000000000000000 R14: 00005d771d88f0d0 R15: 00005d771d895710 [86.892304] </TASK> Call asynchronous variant of dma_fence_work_commit() in that case. v3: Provide more verbose in-line comment (Andi), - mention target environments in commit message. Fixes: 7d1c261 ("drm/i915: Take reservation lock around i915_vma_pin.") Closes: https://gitlab.freedesktop.org/drm/i915/kernel/-/issues/14985 Cc: Andi Shyti <andi.shyti@kernel.org> Signed-off-by: Janusz Krzysztofik <janusz.krzysztofik@linux.intel.com> Reviewed-by: Sebastian Brzezinka <sebastian.brzezinka@intel.com> Reviewed-by: Krzysztof Karas <krzysztof.karas@intel.com> Acked-by: Andi Shyti <andi.shyti@linux.intel.com> Signed-off-by: Andi Shyti <andi.shyti@linux.intel.com> Link: https://lore.kernel.org/r/20251023082925.351307-6-janusz.krzysztofik@linux.intel.com
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Jakub reported an MPTCP deadlock at fallback time: WARNING: possible recursive locking detected 6.18.0-rc7-virtme #1 Not tainted -------------------------------------------- mptcp_connect/20858 is trying to acquire lock: ff1100001da18b60 (&msk->fallback_lock){+.-.}-{3:3}, at: __mptcp_try_fallback+0xd8/0x280 but task is already holding lock: ff1100001da18b60 (&msk->fallback_lock){+.-.}-{3:3}, at: __mptcp_retrans+0x352/0xaa0 other info that might help us debug this: Possible unsafe locking scenario: CPU0 ---- lock(&msk->fallback_lock); lock(&msk->fallback_lock); *** DEADLOCK *** May be due to missing lock nesting notation 3 locks held by mptcp_connect/20858: #0: ff1100001da18290 (sk_lock-AF_INET){+.+.}-{0:0}, at: mptcp_sendmsg+0x114/0x1bc0 #1: ff1100001db40fd0 (k-sk_lock-AF_INET#2){+.+.}-{0:0}, at: __mptcp_retrans+0x2cb/0xaa0 #2: ff1100001da18b60 (&msk->fallback_lock){+.-.}-{3:3}, at: __mptcp_retrans+0x352/0xaa0 stack backtrace: CPU: 0 UID: 0 PID: 20858 Comm: mptcp_connect Not tainted 6.18.0-rc7-virtme #1 PREEMPT(full) Hardware name: Bochs, BIOS Bochs 01/01/2011 Call Trace: <TASK> dump_stack_lvl+0x6f/0xa0 print_deadlock_bug.cold+0xc0/0xcd validate_chain+0x2ff/0x5f0 __lock_acquire+0x34c/0x740 lock_acquire.part.0+0xbc/0x260 _raw_spin_lock_bh+0x38/0x50 __mptcp_try_fallback+0xd8/0x280 mptcp_sendmsg_frag+0x16c2/0x3050 __mptcp_retrans+0x421/0xaa0 mptcp_release_cb+0x5aa/0xa70 release_sock+0xab/0x1d0 mptcp_sendmsg+0xd5b/0x1bc0 sock_write_iter+0x281/0x4d0 new_sync_write+0x3c5/0x6f0 vfs_write+0x65e/0xbb0 ksys_write+0x17e/0x200 do_syscall_64+0xbb/0xfd0 entry_SYSCALL_64_after_hwframe+0x4b/0x53 RIP: 0033:0x7fa5627cbc5e Code: 4d 89 d8 e8 14 bd 00 00 4c 8b 5d f8 41 8b 93 08 03 00 00 59 5e 48 83 f8 fc 74 11 c9 c3 0f 1f 80 00 00 00 00 48 8b 45 10 0f 05 <c9> c3 83 e2 39 83 fa 08 75 e7 e8 13 ff ff ff 0f 1f 00 f3 0f 1e fa RSP: 002b:00007fff1fe14700 EFLAGS: 00000202 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 0000000000000005 RCX: 00007fa5627cbc5e RDX: 0000000000001f9c RSI: 00007fff1fe16984 RDI: 0000000000000005 RBP: 00007fff1fe14710 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000202 R12: 00007fff1fe16920 R13: 0000000000002000 R14: 0000000000001f9c R15: 0000000000001f9c The packet scheduler could attempt a reinjection after receiving an MP_FAIL and before the infinite map has been transmitted, causing a deadlock since MPTCP needs to do the reinjection atomically from WRT fallback. Address the issue explicitly avoiding the reinjection in the critical scenario. Note that this is the only fallback critical section that could potentially send packets and hit the double-lock. Reported-by: Jakub Kicinski <kuba@kernel.org> Closes: https://netdev-ctrl.bots.linux.dev/logs/vmksft/mptcp-dbg/results/412720/1-mptcp-join-sh/stderr Fixes: f8a1d9b ("mptcp: make fallback action and fallback decision atomic") Cc: stable@vger.kernel.org Signed-off-by: Paolo Abeni <pabeni@redhat.com> Reviewed-by: Matthieu Baerts (NGI0) <matttbe@kernel.org> Signed-off-by: Matthieu Baerts (NGI0) <matttbe@kernel.org> Link: https://patch.msgid.link/20251205-net-mptcp-misc-fixes-6-19-rc1-v1-4-9e4781a6c1b8@kernel.org Signed-off-by: Jakub Kicinski <kuba@kernel.org>
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Petr Machata says: ==================== selftests: forwarding: vxlan_bridge_1q_mc_ul: Fix flakiness The net/forwarding/vxlan_bridge_1q_mc_ul selftest runs an overlay traffic, forwarded over a multicast-routed VXLAN underlay. In order to determine whether packets reach their intended destination, it uses a TC match. For convenience, it uses a flower match, which however does not allow matching on the encapsulated packet. So various service traffic ends up being indistinguishable from the test packets, and ends up confusing the test. To alleviate the problem, the test uses sleep to allow the necessary service traffic to run and clear the channel, before running the test traffic. This worked for a while, but lately we have nevertheless seen flakiness of the test in the CI. In this patchset, first generalize tc_rule_stats_get() to support u32 in patch #1, then in patch #2 convert the test to use u32 to allow parsing deeper into the packet, and in #3 drop the now-unnecessary sleep. ==================== Link: https://patch.msgid.link/cover.1765289566.git.petrm@nvidia.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
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The IPv4 code path in __ip_vs_get_out_rt() calls dst_link_failure() without ensuring skb->dev is set, leading to a NULL pointer dereference in fib_compute_spec_dst() when ipv4_link_failure() attempts to send ICMP destination unreachable messages. The issue emerged after commit ed0de45 ("ipv4: recompile ip options in ipv4_link_failure") started calling __ip_options_compile() from ipv4_link_failure(). This code path eventually calls fib_compute_spec_dst() which dereferences skb->dev. An attempt was made to fix the NULL skb->dev dereference in commit 0113d9c ("ipv4: fix null-deref in ipv4_link_failure"), but it only addressed the immediate dev_net(skb->dev) dereference by using a fallback device. The fix was incomplete because fib_compute_spec_dst() later in the call chain still accesses skb->dev directly, which remains NULL when IPVS calls dst_link_failure(). The crash occurs when: 1. IPVS processes a packet in NAT mode with a misconfigured destination 2. Route lookup fails in __ip_vs_get_out_rt() before establishing a route 3. The error path calls dst_link_failure(skb) with skb->dev == NULL 4. ipv4_link_failure() → ipv4_send_dest_unreach() → __ip_options_compile() → fib_compute_spec_dst() 5. fib_compute_spec_dst() dereferences NULL skb->dev Apply the same fix used for IPv6 in commit 326bf17 ("ipvs: fix ipv6 route unreach panic"): set skb->dev from skb_dst(skb)->dev before calling dst_link_failure(). KASAN: null-ptr-deref in range [0x0000000000000328-0x000000000000032f] CPU: 1 PID: 12732 Comm: syz.1.3469 Not tainted 6.6.114 #2 RIP: 0010:__in_dev_get_rcu include/linux/inetdevice.h:233 RIP: 0010:fib_compute_spec_dst+0x17a/0x9f0 net/ipv4/fib_frontend.c:285 Call Trace: <TASK> spec_dst_fill net/ipv4/ip_options.c:232 spec_dst_fill net/ipv4/ip_options.c:229 __ip_options_compile+0x13a1/0x17d0 net/ipv4/ip_options.c:330 ipv4_send_dest_unreach net/ipv4/route.c:1252 ipv4_link_failure+0x702/0xb80 net/ipv4/route.c:1265 dst_link_failure include/net/dst.h:437 __ip_vs_get_out_rt+0x15fd/0x19e0 net/netfilter/ipvs/ip_vs_xmit.c:412 ip_vs_nat_xmit+0x1d8/0xc80 net/netfilter/ipvs/ip_vs_xmit.c:764 Fixes: ed0de45 ("ipv4: recompile ip options in ipv4_link_failure") Signed-off-by: Slavin Liu <slavin452@gmail.com> Acked-by: Julian Anastasov <ja@ssi.bg> Signed-off-by: Florian Westphal <fw@strlen.de>
johnhubbard
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Fix a loop scenario of ethx:egress->ethx:egress
Example setup to reproduce:
tc qdisc add dev ethx root handle 1: drr
tc filter add dev ethx parent 1: protocol ip prio 1 matchall \
action mirred egress redirect dev ethx
Now ping out of ethx and you get a deadlock:
[ 116.892898][ T307] ============================================
[ 116.893182][ T307] WARNING: possible recursive locking detected
[ 116.893418][ T307] 6.18.0-rc6-01205-ge05021a829b8-dirty torvalds#204 Not tainted
[ 116.893682][ T307] --------------------------------------------
[ 116.893926][ T307] ping/307 is trying to acquire lock:
[ 116.894133][ T307] ffff88800c122908 (&sch->root_lock_key){+...}-{3:3}, at: __dev_queue_xmit+0x2210/0x3b50
[ 116.894517][ T307]
[ 116.894517][ T307] but task is already holding lock:
[ 116.894836][ T307] ffff88800c122908 (&sch->root_lock_key){+...}-{3:3}, at: __dev_queue_xmit+0x2210/0x3b50
[ 116.895252][ T307]
[ 116.895252][ T307] other info that might help us debug this:
[ 116.895608][ T307] Possible unsafe locking scenario:
[ 116.895608][ T307]
[ 116.895901][ T307] CPU0
[ 116.896057][ T307] ----
[ 116.896200][ T307] lock(&sch->root_lock_key);
[ 116.896392][ T307] lock(&sch->root_lock_key);
[ 116.896605][ T307]
[ 116.896605][ T307] *** DEADLOCK ***
[ 116.896605][ T307]
[ 116.896864][ T307] May be due to missing lock nesting notation
[ 116.896864][ T307]
[ 116.897123][ T307] 6 locks held by ping/307:
[ 116.897302][ T307] #0: ffff88800b4b0250 (sk_lock-AF_INET){+.+.}-{0:0}, at: raw_sendmsg+0xb20/0x2cf0
[ 116.897808][ T307] #1: ffffffff88c839c0 (rcu_read_lock){....}-{1:3}, at: ip_output+0xa9/0x600
[ 116.898138][ T307] #2: ffffffff88c839c0 (rcu_read_lock){....}-{1:3}, at: ip_finish_output2+0x2c6/0x1ee0
[ 116.898459][ T307] #3: ffffffff88c83960 (rcu_read_lock_bh){....}-{1:3}, at: __dev_queue_xmit+0x200/0x3b50
[ 116.898782][ T307] #4: ffff88800c122908 (&sch->root_lock_key){+...}-{3:3}, at: __dev_queue_xmit+0x2210/0x3b50
[ 116.899132][ T307] #5: ffffffff88c83960 (rcu_read_lock_bh){....}-{1:3}, at: __dev_queue_xmit+0x200/0x3b50
[ 116.899442][ T307]
[ 116.899442][ T307] stack backtrace:
[ 116.899667][ T307] CPU: 2 UID: 0 PID: 307 Comm: ping Not tainted 6.18.0-rc6-01205-ge05021a829b8-dirty torvalds#204 PREEMPT(voluntary)
[ 116.899672][ T307] Hardware name: Bochs Bochs, BIOS Bochs 01/01/2011
[ 116.899675][ T307] Call Trace:
[ 116.899678][ T307] <TASK>
[ 116.899680][ T307] dump_stack_lvl+0x6f/0xb0
[ 116.899688][ T307] print_deadlock_bug.cold+0xc0/0xdc
[ 116.899695][ T307] __lock_acquire+0x11f7/0x1be0
[ 116.899704][ T307] lock_acquire+0x162/0x300
[ 116.899707][ T307] ? __dev_queue_xmit+0x2210/0x3b50
[ 116.899713][ T307] ? srso_alias_return_thunk+0x5/0xfbef5
[ 116.899717][ T307] ? stack_trace_save+0x93/0xd0
[ 116.899723][ T307] _raw_spin_lock+0x30/0x40
[ 116.899728][ T307] ? __dev_queue_xmit+0x2210/0x3b50
[ 116.899731][ T307] __dev_queue_xmit+0x2210/0x3b50
Fixes: 178ca30 ("Revert "net/sched: Fix mirred deadlock on device recursion"")
Tested-by: Victor Nogueira <victor@mojatatu.com>
Signed-off-by: Jamal Hadi Salim <jhs@mojatatu.com>
Link: https://patch.msgid.link/20251210162255.1057663-1-jhs@mojatatu.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
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A race condition was found in sg_proc_debug_helper(). It was observed on a system using an IBM LTO-9 SAS Tape Drive (ULTRIUM-TD9) and monitoring /proc/scsi/sg/debug every second. A very large elapsed time would sometimes appear. This is caused by two race conditions. We reproduced the issue with an IBM ULTRIUM-HH9 tape drive on an x86_64 architecture. A patched kernel was built, and the race condition could not be observed anymore after the application of this patch. A reproducer C program utilising the scsi_debug module was also built by Changhui Zhong and can be viewed here: https://github.com/MichaelRabek/linux-tests/blob/master/drivers/scsi/sg/sg_race_trigger.c The first race happens between the reading of hp->duration in sg_proc_debug_helper() and request completion in sg_rq_end_io(). The hp->duration member variable may hold either of two types of information: #1 - The start time of the request. This value is present while the request is not yet finished. #2 - The total execution time of the request (end_time - start_time). If sg_proc_debug_helper() executes *after* the value of hp->duration was changed from #1 to #2, but *before* srp->done is set to 1 in sg_rq_end_io(), a fresh timestamp is taken in the else branch, and the elapsed time (value type #2) is subtracted from a timestamp, which cannot yield a valid elapsed time (which is a type #2 value as well). To fix this issue, the value of hp->duration must change under the protection of the sfp->rq_list_lock in sg_rq_end_io(). Since sg_proc_debug_helper() takes this read lock, the change to srp->done and srp->header.duration will happen atomically from the perspective of sg_proc_debug_helper() and the race condition is thus eliminated. The second race condition happens between sg_proc_debug_helper() and sg_new_write(). Even though hp->duration is set to the current time stamp in sg_add_request() under the write lock's protection, it gets overwritten by a call to get_sg_io_hdr(), which calls copy_from_user() to copy struct sg_io_hdr from userspace into kernel space. hp->duration is set to the start time again in sg_common_write(). If sg_proc_debug_helper() is called between these two calls, an arbitrary value set by userspace (usually zero) is used to compute the elapsed time. To fix this issue, hp->duration must be set to the current timestamp again after get_sg_io_hdr() returns successfully. A small race window still exists between get_sg_io_hdr() and setting hp->duration, but this window is only a few instructions wide and does not result in observable issues in practice, as confirmed by testing. Additionally, we fix the format specifier from %d to %u for printing unsigned int values in sg_proc_debug_helper(). Signed-off-by: Michal Rábek <mrabek@redhat.com> Suggested-by: Tomas Henzl <thenzl@redhat.com> Tested-by: Changhui Zhong <czhong@redhat.com> Reviewed-by: Ewan D. Milne <emilne@redhat.com> Reviewed-by: John Meneghini <jmeneghi@redhat.com> Reviewed-by: Tomas Henzl <thenzl@redhat.com> Link: https://patch.msgid.link/20251212160900.64924-1-mrabek@redhat.com Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
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When a page is freed it coalesces with a buddy into a higher order page while possible. When the buddy page migrate type differs, it is expected to be updated to match the one of the page being freed. However, only the first pageblock of the buddy page is updated, while the rest of the pageblocks are left unchanged. That causes warnings in later expand() and other code paths (like below), since an inconsistency between migration type of the list containing the page and the page-owned pageblocks migration types is introduced. [ 308.986589] ------------[ cut here ]------------ [ 308.987227] page type is 0, passed migratetype is 1 (nr=256) [ 308.987275] WARNING: CPU: 1 PID: 5224 at mm/page_alloc.c:812 expand+0x23c/0x270 [ 308.987293] Modules linked in: algif_hash(E) af_alg(E) nft_fib_inet(E) nft_fib_ipv4(E) nft_fib_ipv6(E) nft_fib(E) nft_reject_inet(E) nf_reject_ipv4(E) nf_reject_ipv6(E) nft_reject(E) nft_ct(E) nft_chain_nat(E) nf_nat(E) nf_conntrack(E) nf_defrag_ipv6(E) nf_defrag_ipv4(E) nf_tables(E) s390_trng(E) vfio_ccw(E) mdev(E) vfio_iommu_type1(E) vfio(E) sch_fq_codel(E) drm(E) i2c_core(E) drm_panel_orientation_quirks(E) loop(E) nfnetlink(E) vsock_loopback(E) vmw_vsock_virtio_transport_common(E) vsock(E) ctcm(E) fsm(E) diag288_wdt(E) watchdog(E) zfcp(E) scsi_transport_fc(E) ghash_s390(E) prng(E) aes_s390(E) des_generic(E) des_s390(E) libdes(E) sha3_512_s390(E) sha3_256_s390(E) sha_common(E) paes_s390(E) crypto_engine(E) pkey_cca(E) pkey_ep11(E) zcrypt(E) rng_core(E) pkey_pckmo(E) pkey(E) autofs4(E) [ 308.987439] Unloaded tainted modules: hmac_s390(E):2 [ 308.987650] CPU: 1 UID: 0 PID: 5224 Comm: mempig_verify Kdump: loaded Tainted: G E 6.18.0-gcc-bpf-debug torvalds#431 PREEMPT [ 308.987657] Tainted: [E]=UNSIGNED_MODULE [ 308.987661] Hardware name: IBM 3906 M04 704 (z/VM 7.3.0) [ 308.987666] Krnl PSW : 0404f00180000000 00000349976fa600 (expand+0x240/0x270) [ 308.987676] R:0 T:1 IO:0 EX:0 Key:0 M:1 W:0 P:0 AS:3 CC:3 PM:0 RI:0 EA:3 [ 308.987682] Krnl GPRS: 0000034980000004 0000000000000005 0000000000000030 000003499a0e6d88 [ 308.987688] 0000000000000005 0000034980000005 000002be803ac000 0000023efe6c8300 [ 308.987692] 0000000000000008 0000034998d57290 000002be00000100 0000023e00000008 [ 308.987696] 0000000000000000 0000000000000000 00000349976fa5fc 000002c99b1eb6f0 [ 308.987708] Krnl Code: 00000349976fa5f0: c020008a02f2 larl %r2,000003499883abd4 00000349976fa5f6: c0e5ffe3f4b5 brasl %r14,0000034997378f60 #00000349976fa5fc: af000000 mc 0,0 >00000349976fa600: a7f4ff4c brc 15,00000349976fa498 00000349976fa604: b9040026 lgr %r2,%r6 00000349976fa608: c0300088317f larl %r3,0000034998800906 00000349976fa60e: c0e5fffdb6e1 brasl %r14,00000349976b13d0 00000349976fa614: af000000 mc 0,0 [ 308.987734] Call Trace: [ 308.987738] [<00000349976fa600>] expand+0x240/0x270 [ 308.987744] ([<00000349976fa5fc>] expand+0x23c/0x270) [ 308.987749] [<00000349976ff95e>] rmqueue_bulk+0x71e/0x940 [ 308.987754] [<00000349976ffd7e>] __rmqueue_pcplist+0x1fe/0x2a0 [ 308.987759] [<0000034997700966>] rmqueue.isra.0+0xb46/0xf40 [ 308.987763] [<0000034997703ec8>] get_page_from_freelist+0x198/0x8d0 [ 308.987768] [<0000034997706fa8>] __alloc_frozen_pages_noprof+0x198/0x400 [ 308.987774] [<00000349977536f8>] alloc_pages_mpol+0xb8/0x220 [ 308.987781] [<0000034997753bf6>] folio_alloc_mpol_noprof+0x26/0xc0 [ 308.987786] [<0000034997753e4c>] vma_alloc_folio_noprof+0x6c/0xa0 [ 308.987791] [<0000034997775b22>] vma_alloc_anon_folio_pmd+0x42/0x240 [ 308.987799] [<000003499777bfea>] __do_huge_pmd_anonymous_page+0x3a/0x210 [ 308.987804] [<00000349976cb08e>] __handle_mm_fault+0x4de/0x500 [ 308.987809] [<00000349976cb14c>] handle_mm_fault+0x9c/0x3a0 [ 308.987813] [<000003499734d70e>] do_exception+0x1de/0x540 [ 308.987822] [<0000034998387390>] __do_pgm_check+0x130/0x220 [ 308.987830] [<000003499839a934>] pgm_check_handler+0x114/0x160 [ 308.987838] 3 locks held by mempig_verify/5224: [ 308.987842] #0: 0000023ea44c1e08 (vm_lock){++++}-{0:0}, at: lock_vma_under_rcu+0xb2/0x2a0 [ 308.987859] #1: 0000023ee4d41b18 (&pcp->lock){+.+.}-{2:2}, at: rmqueue.isra.0+0xad6/0xf40 [ 308.987871] #2: 0000023efe6c8998 (&zone->lock){..-.}-{2:2}, at: rmqueue_bulk+0x5a/0x940 [ 308.987886] Last Breaking-Event-Address: [ 308.987890] [<0000034997379096>] __warn_printk+0x136/0x140 [ 308.987897] irq event stamp: 52330356 [ 308.987901] hardirqs last enabled at (52330355): [<000003499838742e>] __do_pgm_check+0x1ce/0x220 [ 308.987907] hardirqs last disabled at (52330356): [<000003499839932e>] _raw_spin_lock_irqsave+0x9e/0xe0 [ 308.987913] softirqs last enabled at (52329882): [<0000034997383786>] handle_softirqs+0x2c6/0x530 [ 308.987922] softirqs last disabled at (52329859): [<0000034997382f86>] __irq_exit_rcu+0x126/0x140 [ 308.987929] ---[ end trace 0000000000000000 ]--- [ 308.987936] ------------[ cut here ]------------ [ 308.987940] page type is 0, passed migratetype is 1 (nr=256) [ 308.987951] WARNING: CPU: 1 PID: 5224 at mm/page_alloc.c:860 __del_page_from_free_list+0x1be/0x1e0 [ 308.987960] Modules linked in: algif_hash(E) af_alg(E) nft_fib_inet(E) nft_fib_ipv4(E) nft_fib_ipv6(E) nft_fib(E) nft_reject_inet(E) nf_reject_ipv4(E) nf_reject_ipv6(E) nft_reject(E) nft_ct(E) nft_chain_nat(E) nf_nat(E) nf_conntrack(E) nf_defrag_ipv6(E) nf_defrag_ipv4(E) nf_tables(E) s390_trng(E) vfio_ccw(E) mdev(E) vfio_iommu_type1(E) vfio(E) sch_fq_codel(E) drm(E) i2c_core(E) drm_panel_orientation_quirks(E) loop(E) nfnetlink(E) vsock_loopback(E) vmw_vsock_virtio_transport_common(E) vsock(E) ctcm(E) fsm(E) diag288_wdt(E) watchdog(E) zfcp(E) scsi_transport_fc(E) ghash_s390(E) prng(E) aes_s390(E) des_generic(E) des_s390(E) libdes(E) sha3_512_s390(E) sha3_256_s390(E) sha_common(E) paes_s390(E) crypto_engine(E) pkey_cca(E) pkey_ep11(E) zcrypt(E) rng_core(E) pkey_pckmo(E) pkey(E) autofs4(E) [ 308.988070] Unloaded tainted modules: hmac_s390(E):2 [ 308.988087] CPU: 1 UID: 0 PID: 5224 Comm: mempig_verify Kdump: loaded Tainted: G W E 6.18.0-gcc-bpf-debug torvalds#431 PREEMPT [ 308.988095] Tainted: [W]=WARN, [E]=UNSIGNED_MODULE [ 308.988100] Hardware name: IBM 3906 M04 704 (z/VM 7.3.0) [ 308.988105] Krnl PSW : 0404f00180000000 00000349976f9e32 (__del_page_from_free_list+0x1c2/0x1e0) [ 308.988118] R:0 T:1 IO:0 EX:0 Key:0 M:1 W:0 P:0 AS:3 CC:3 PM:0 RI:0 EA:3 [ 308.988127] Krnl GPRS: 0000034980000004 0000000000000005 0000000000000030 000003499a0e6d88 [ 308.988133] 0000000000000005 0000034980000005 0000034998d57290 0000023efe6c8300 [ 308.988139] 0000000000000001 0000000000000008 000002be00000100 000002be803ac000 [ 308.988144] 0000000000000000 0000000000000001 00000349976f9e2e 000002c99b1eb728 [ 308.988153] Krnl Code: 00000349976f9e22: c020008a06d9 larl %r2,000003499883abd4 00000349976f9e28: c0e5ffe3f89c brasl %r14,0000034997378f60 #00000349976f9e2e: af000000 mc 0,0 >00000349976f9e32: a7f4ff4e brc 15,00000349976f9cce 00000349976f9e36: b904002b lgr %r2,%r11 00000349976f9e3a: c030008a06e7 larl %r3,000003499883ac08 00000349976f9e40: c0e5fffdbac8 brasl %r14,00000349976b13d0 00000349976f9e46: af000000 mc 0,0 [ 308.988184] Call Trace: [ 308.988188] [<00000349976f9e32>] __del_page_from_free_list+0x1c2/0x1e0 [ 308.988195] ([<00000349976f9e2e>] __del_page_from_free_list+0x1be/0x1e0) [ 308.988202] [<00000349976ff946>] rmqueue_bulk+0x706/0x940 [ 308.988208] [<00000349976ffd7e>] __rmqueue_pcplist+0x1fe/0x2a0 [ 308.988214] [<0000034997700966>] rmqueue.isra.0+0xb46/0xf40 [ 308.988221] [<0000034997703ec8>] get_page_from_freelist+0x198/0x8d0 [ 308.988227] [<0000034997706fa8>] __alloc_frozen_pages_noprof+0x198/0x400 [ 308.988233] [<00000349977536f8>] alloc_pages_mpol+0xb8/0x220 [ 308.988240] [<0000034997753bf6>] folio_alloc_mpol_noprof+0x26/0xc0 [ 308.988247] [<0000034997753e4c>] vma_alloc_folio_noprof+0x6c/0xa0 [ 308.988253] [<0000034997775b22>] vma_alloc_anon_folio_pmd+0x42/0x240 [ 308.988260] [<000003499777bfea>] __do_huge_pmd_anonymous_page+0x3a/0x210 [ 308.988267] [<00000349976cb08e>] __handle_mm_fault+0x4de/0x500 [ 308.988273] [<00000349976cb14c>] handle_mm_fault+0x9c/0x3a0 [ 308.988279] [<000003499734d70e>] do_exception+0x1de/0x540 [ 308.988286] [<0000034998387390>] __do_pgm_check+0x130/0x220 [ 308.988293] [<000003499839a934>] pgm_check_handler+0x114/0x160 [ 308.988300] 3 locks held by mempig_verify/5224: [ 308.988305] #0: 0000023ea44c1e08 (vm_lock){++++}-{0:0}, at: lock_vma_under_rcu+0xb2/0x2a0 [ 308.988322] #1: 0000023ee4d41b18 (&pcp->lock){+.+.}-{2:2}, at: rmqueue.isra.0+0xad6/0xf40 [ 308.988334] #2: 0000023efe6c8998 (&zone->lock){..-.}-{2:2}, at: rmqueue_bulk+0x5a/0x940 [ 308.988346] Last Breaking-Event-Address: [ 308.988350] [<0000034997379096>] __warn_printk+0x136/0x140 [ 308.988356] irq event stamp: 52330356 [ 308.988360] hardirqs last enabled at (52330355): [<000003499838742e>] __do_pgm_check+0x1ce/0x220 [ 308.988366] hardirqs last disabled at (52330356): [<000003499839932e>] _raw_spin_lock_irqsave+0x9e/0xe0 [ 308.988373] softirqs last enabled at (52329882): [<0000034997383786>] handle_softirqs+0x2c6/0x530 [ 308.988380] softirqs last disabled at (52329859): [<0000034997382f86>] __irq_exit_rcu+0x126/0x140 [ 308.988388] ---[ end trace 0000000000000000 ]--- Link: https://lkml.kernel.org/r/20251215081002.3353900A9c-agordeev@linux.ibm.com Link: https://lkml.kernel.org/r/20251212151457.3898073Add-agordeev@linux.ibm.com Fixes: e6cf9e1 ("mm: page_alloc: fix up block types when merging compatible blocks") Signed-off-by: Alexander Gordeev <agordeev@linux.ibm.com> Reported-by: Marc Hartmayer <mhartmay@linux.ibm.com> Closes: https://lore.kernel.org/linux-mm/87wmalyktd.fsf@linux.ibm.com/ Acked-by: Vlastimil Babka <vbabka@suse.cz> Acked-by: Johannes Weiner <hannes@cmpxchg.org> Reviewed-by: Wei Yang <richard.weiyang@gmail.com> Cc: Marc Hartmayer <mhartmay@linux.ibm.com> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
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When running the Rust maple tree kunit tests with lockdep, you may trigger a warning that looks like this: lib/maple_tree.c:780 suspicious rcu_dereference_check() usage! other info that might help us debug this: rcu_scheduler_active = 2, debug_locks = 1 no locks held by kunit_try_catch/344. stack backtrace: CPU: 3 UID: 0 PID: 344 Comm: kunit_try_catch Tainted: G N 6.19.0-rc1+ #2 NONE Tainted: [N]=TEST Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS rel-1.17.0-0-gb52ca86e094d-prebuilt.qemu.org 04/01/2014 Call Trace: <TASK> dump_stack_lvl+0x71/0x90 lockdep_rcu_suspicious+0x150/0x190 mas_start+0x104/0x150 mas_find+0x179/0x240 _RINvNtCs5QSdWC790r4_4core3ptr13drop_in_placeINtNtCs1cdwasc6FUb_6kernel10maple_tree9MapleTreeINtNtNtBL_5alloc4kbox3BoxlNtNtB1x_9allocator7KmallocEEECsgxAQYCfdR72_25doctests_kernel_generated+0xaf/0x130 rust_doctest_kernel_maple_tree_rs_0+0x600/0x6b0 ? lock_release+0xeb/0x2a0 ? kunit_try_catch_run+0x210/0x210 kunit_try_run_case+0x74/0x160 ? kunit_try_catch_run+0x210/0x210 kunit_generic_run_threadfn_adapter+0x12/0x30 kthread+0x21c/0x230 ? __do_trace_sched_kthread_stop_ret+0x40/0x40 ret_from_fork+0x16c/0x270 ? __do_trace_sched_kthread_stop_ret+0x40/0x40 ret_from_fork_asm+0x11/0x20 </TASK> This is because the destructor of maple tree calls mas_find() without taking rcu_read_lock() or the spinlock. Doing that is actually ok in this case since the destructor has exclusive access to the entire maple tree, but it triggers a lockdep warning. To fix that, take the rcu read lock. In the future, it's possible that memory reclaim could gain a feature where it reallocates entries in maple trees even if no user-code is touching it. If that feature is added, then this use of rcu read lock would become load-bearing, so I did not make it conditional on lockdep. We have to repeatedly take and release rcu because the destructor of T might perform operations that sleep. Link: https://lkml.kernel.org/r/20251217-maple-drop-rcu-v1-1-702af063573f@google.com Fixes: da939ef ("rust: maple_tree: add MapleTree") Signed-off-by: Alice Ryhl <aliceryhl@google.com> Reported-by: Andreas Hindborg <a.hindborg@kernel.org> Closes: https://rust-for-linux.zulipchat.com/#narrow/channel/x/topic/x/near/564215108 Reviewed-by: Gary Guo <gary@garyguo.net> Reviewed-by: Daniel Almeida <daniel.almeida@collabora.com> Cc: Andrew Ballance <andrewjballance@gmail.com> Cc: Björn Roy Baron <bjorn3_gh@protonmail.com> Cc: Boqun Feng <boqun.feng@gmail.com> Cc: Danilo Krummrich <dakr@kernel.org> Cc: Liam Howlett <liam.howlett@oracle.com> Cc: Matthew Wilcox (Oracle) <willy@infradead.org> Cc: Miguel Ojeda <ojeda@kernel.org> Cc: Trevor Gross <tmgross@umich.edu> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
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Jan 18, 2026
… to macb_open() In the non-RT kernel, local_bh_disable() merely disables preemption, whereas it maps to an actual spin lock in the RT kernel. Consequently, when attempting to refill RX buffers via netdev_alloc_skb() in macb_mac_link_up(), a deadlock scenario arises as follows: WARNING: possible circular locking dependency detected 6.18.0-08691-g2061f18ad76e torvalds#39 Not tainted ------------------------------------------------------ kworker/0:0/8 is trying to acquire lock: ffff00080369bbe0 (&bp->lock){+.+.}-{3:3}, at: macb_start_xmit+0x808/0xb7c but task is already holding lock: ffff000803698e58 (&queue->tx_ptr_lock){+...}-{3:3}, at: macb_start_xmit +0x148/0xb7c which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #3 (&queue->tx_ptr_lock){+...}-{3:3}: rt_spin_lock+0x50/0x1f0 macb_start_xmit+0x148/0xb7c dev_hard_start_xmit+0x94/0x284 sch_direct_xmit+0x8c/0x37c __dev_queue_xmit+0x708/0x1120 neigh_resolve_output+0x148/0x28c ip6_finish_output2+0x2c0/0xb2c __ip6_finish_output+0x114/0x308 ip6_output+0xc4/0x4a4 mld_sendpack+0x220/0x68c mld_ifc_work+0x2a8/0x4f4 process_one_work+0x20c/0x5f8 worker_thread+0x1b0/0x35c kthread+0x144/0x200 ret_from_fork+0x10/0x20 -> #2 (_xmit_ETHER#2){+...}-{3:3}: rt_spin_lock+0x50/0x1f0 sch_direct_xmit+0x11c/0x37c __dev_queue_xmit+0x708/0x1120 neigh_resolve_output+0x148/0x28c ip6_finish_output2+0x2c0/0xb2c __ip6_finish_output+0x114/0x308 ip6_output+0xc4/0x4a4 mld_sendpack+0x220/0x68c mld_ifc_work+0x2a8/0x4f4 process_one_work+0x20c/0x5f8 worker_thread+0x1b0/0x35c kthread+0x144/0x200 ret_from_fork+0x10/0x20 -> #1 ((softirq_ctrl.lock)){+.+.}-{3:3}: lock_release+0x250/0x348 __local_bh_enable_ip+0x7c/0x240 __netdev_alloc_skb+0x1b4/0x1d8 gem_rx_refill+0xdc/0x240 gem_init_rings+0xb4/0x108 macb_mac_link_up+0x9c/0x2b4 phylink_resolve+0x170/0x614 process_one_work+0x20c/0x5f8 worker_thread+0x1b0/0x35c kthread+0x144/0x200 ret_from_fork+0x10/0x20 -> #0 (&bp->lock){+.+.}-{3:3}: __lock_acquire+0x15a8/0x2084 lock_acquire+0x1cc/0x350 rt_spin_lock+0x50/0x1f0 macb_start_xmit+0x808/0xb7c dev_hard_start_xmit+0x94/0x284 sch_direct_xmit+0x8c/0x37c __dev_queue_xmit+0x708/0x1120 neigh_resolve_output+0x148/0x28c ip6_finish_output2+0x2c0/0xb2c __ip6_finish_output+0x114/0x308 ip6_output+0xc4/0x4a4 mld_sendpack+0x220/0x68c mld_ifc_work+0x2a8/0x4f4 process_one_work+0x20c/0x5f8 worker_thread+0x1b0/0x35c kthread+0x144/0x200 ret_from_fork+0x10/0x20 other info that might help us debug this: Chain exists of: &bp->lock --> _xmit_ETHER#2 --> &queue->tx_ptr_lock Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(&queue->tx_ptr_lock); lock(_xmit_ETHER#2); lock(&queue->tx_ptr_lock); lock(&bp->lock); *** DEADLOCK *** Call trace: show_stack+0x18/0x24 (C) dump_stack_lvl+0xa0/0xf0 dump_stack+0x18/0x24 print_circular_bug+0x28c/0x370 check_noncircular+0x198/0x1ac __lock_acquire+0x15a8/0x2084 lock_acquire+0x1cc/0x350 rt_spin_lock+0x50/0x1f0 macb_start_xmit+0x808/0xb7c dev_hard_start_xmit+0x94/0x284 sch_direct_xmit+0x8c/0x37c __dev_queue_xmit+0x708/0x1120 neigh_resolve_output+0x148/0x28c ip6_finish_output2+0x2c0/0xb2c __ip6_finish_output+0x114/0x308 ip6_output+0xc4/0x4a4 mld_sendpack+0x220/0x68c mld_ifc_work+0x2a8/0x4f4 process_one_work+0x20c/0x5f8 worker_thread+0x1b0/0x35c kthread+0x144/0x200 ret_from_fork+0x10/0x20 Notably, invoking the mog_init_rings() callback upon link establishment is unnecessary. Instead, we can exclusively call mog_init_rings() within the ndo_open() callback. This adjustment resolves the deadlock issue. Furthermore, since MACB_CAPS_MACB_IS_EMAC cases do not use mog_init_rings() when opening the network interface via at91ether_open(), moving mog_init_rings() to macb_open() also eliminates the MACB_CAPS_MACB_IS_EMAC check. Fixes: 633e98a ("net: macb: use resolved link config in mac_link_up()") Cc: stable@vger.kernel.org Suggested-by: Kevin Hao <kexin.hao@windriver.com> Signed-off-by: Xiaolei Wang <xiaolei.wang@windriver.com> Link: https://patch.msgid.link/20251222015624.1994551-1-xiaolei.wang@windriver.com Signed-off-by: Paolo Abeni <pabeni@redhat.com>
johnhubbard
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Jan 18, 2026
ctx->tcxt_list holds the tasks using this ring, and it's currently
protected by the normal ctx->uring_lock. However, this can cause a
circular locking issue, as reported by syzbot, where cancelations off
exec end up needing to remove an entry from this list:
======================================================
WARNING: possible circular locking dependency detected
syzkaller #0 Tainted: G L
------------------------------------------------------
syz.0.9999/12287 is trying to acquire lock:
ffff88805851c0a8 (&ctx->uring_lock){+.+.}-{4:4}, at: io_uring_del_tctx_node+0xf0/0x2c0 io_uring/tctx.c:179
but task is already holding lock:
ffff88802db5a2e0 (&sig->cred_guard_mutex){+.+.}-{4:4}, at: prepare_bprm_creds fs/exec.c:1360 [inline]
ffff88802db5a2e0 (&sig->cred_guard_mutex){+.+.}-{4:4}, at: bprm_execve+0xb9/0x1400 fs/exec.c:1733
which lock already depends on the new lock.
the existing dependency chain (in reverse order) is:
-> #2 (&sig->cred_guard_mutex){+.+.}-{4:4}:
__mutex_lock_common kernel/locking/mutex.c:614 [inline]
__mutex_lock+0x187/0x1350 kernel/locking/mutex.c:776
proc_pid_attr_write+0x547/0x630 fs/proc/base.c:2837
vfs_write+0x27e/0xb30 fs/read_write.c:684
ksys_write+0x145/0x250 fs/read_write.c:738
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xec/0xf80 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
-> #1 (sb_writers#3){.+.+}-{0:0}:
percpu_down_read_internal include/linux/percpu-rwsem.h:53 [inline]
percpu_down_read_freezable include/linux/percpu-rwsem.h:83 [inline]
__sb_start_write include/linux/fs/super.h:19 [inline]
sb_start_write+0x4d/0x1c0 include/linux/fs/super.h:125
mnt_want_write+0x41/0x90 fs/namespace.c:499
open_last_lookups fs/namei.c:4529 [inline]
path_openat+0xadd/0x3dd0 fs/namei.c:4784
do_filp_open+0x1fa/0x410 fs/namei.c:4814
io_openat2+0x3e0/0x5c0 io_uring/openclose.c:143
__io_issue_sqe+0x181/0x4b0 io_uring/io_uring.c:1792
io_issue_sqe+0x165/0x1060 io_uring/io_uring.c:1815
io_queue_sqe io_uring/io_uring.c:2042 [inline]
io_submit_sqe io_uring/io_uring.c:2320 [inline]
io_submit_sqes+0xbf4/0x2140 io_uring/io_uring.c:2434
__do_sys_io_uring_enter io_uring/io_uring.c:3280 [inline]
__se_sys_io_uring_enter+0x2e0/0x2b60 io_uring/io_uring.c:3219
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xec/0xf80 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
-> #0 (&ctx->uring_lock){+.+.}-{4:4}:
check_prev_add kernel/locking/lockdep.c:3165 [inline]
check_prevs_add kernel/locking/lockdep.c:3284 [inline]
validate_chain kernel/locking/lockdep.c:3908 [inline]
__lock_acquire+0x15a6/0x2cf0 kernel/locking/lockdep.c:5237
lock_acquire+0x107/0x340 kernel/locking/lockdep.c:5868
__mutex_lock_common kernel/locking/mutex.c:614 [inline]
__mutex_lock+0x187/0x1350 kernel/locking/mutex.c:776
io_uring_del_tctx_node+0xf0/0x2c0 io_uring/tctx.c:179
io_uring_clean_tctx+0xd4/0x1a0 io_uring/tctx.c:195
io_uring_cancel_generic+0x6ca/0x7d0 io_uring/cancel.c:646
io_uring_task_cancel include/linux/io_uring.h:24 [inline]
begin_new_exec+0x10ed/0x2440 fs/exec.c:1131
load_elf_binary+0x9f8/0x2d70 fs/binfmt_elf.c:1010
search_binary_handler fs/exec.c:1669 [inline]
exec_binprm fs/exec.c:1701 [inline]
bprm_execve+0x92e/0x1400 fs/exec.c:1753
do_execveat_common+0x510/0x6a0 fs/exec.c:1859
do_execve fs/exec.c:1933 [inline]
__do_sys_execve fs/exec.c:2009 [inline]
__se_sys_execve fs/exec.c:2004 [inline]
__x64_sys_execve+0x94/0xb0 fs/exec.c:2004
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xec/0xf80 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
other info that might help us debug this:
Chain exists of:
&ctx->uring_lock --> sb_writers#3 --> &sig->cred_guard_mutex
Possible unsafe locking scenario:
CPU0 CPU1
---- ----
lock(&sig->cred_guard_mutex);
lock(sb_writers#3);
lock(&sig->cred_guard_mutex);
lock(&ctx->uring_lock);
*** DEADLOCK ***
1 lock held by syz.0.9999/12287:
#0: ffff88802db5a2e0 (&sig->cred_guard_mutex){+.+.}-{4:4}, at: prepare_bprm_creds fs/exec.c:1360 [inline]
#0: ffff88802db5a2e0 (&sig->cred_guard_mutex){+.+.}-{4:4}, at: bprm_execve+0xb9/0x1400 fs/exec.c:1733
stack backtrace:
CPU: 0 UID: 0 PID: 12287 Comm: syz.0.9999 Tainted: G L syzkaller #0 PREEMPT(full)
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
Call Trace:
<TASK>
dump_stack_lvl+0xe8/0x150 lib/dump_stack.c:120
print_circular_bug+0x2e2/0x300 kernel/locking/lockdep.c:2043
check_noncircular+0x12e/0x150 kernel/locking/lockdep.c:2175
check_prev_add kernel/locking/lockdep.c:3165 [inline]
check_prevs_add kernel/locking/lockdep.c:3284 [inline]
validate_chain kernel/locking/lockdep.c:3908 [inline]
__lock_acquire+0x15a6/0x2cf0 kernel/locking/lockdep.c:5237
lock_acquire+0x107/0x340 kernel/locking/lockdep.c:5868
__mutex_lock_common kernel/locking/mutex.c:614 [inline]
__mutex_lock+0x187/0x1350 kernel/locking/mutex.c:776
io_uring_del_tctx_node+0xf0/0x2c0 io_uring/tctx.c:179
io_uring_clean_tctx+0xd4/0x1a0 io_uring/tctx.c:195
io_uring_cancel_generic+0x6ca/0x7d0 io_uring/cancel.c:646
io_uring_task_cancel include/linux/io_uring.h:24 [inline]
begin_new_exec+0x10ed/0x2440 fs/exec.c:1131
load_elf_binary+0x9f8/0x2d70 fs/binfmt_elf.c:1010
search_binary_handler fs/exec.c:1669 [inline]
exec_binprm fs/exec.c:1701 [inline]
bprm_execve+0x92e/0x1400 fs/exec.c:1753
do_execveat_common+0x510/0x6a0 fs/exec.c:1859
do_execve fs/exec.c:1933 [inline]
__do_sys_execve fs/exec.c:2009 [inline]
__se_sys_execve fs/exec.c:2004 [inline]
__x64_sys_execve+0x94/0xb0 fs/exec.c:2004
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xec/0xf80 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7ff3a8b8f749
Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 a8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007ff3a9a97038 EFLAGS: 00000246 ORIG_RAX: 000000000000003b
RAX: ffffffffffffffda RBX: 00007ff3a8de5fa0 RCX: 00007ff3a8b8f749
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000200000000400
RBP: 00007ff3a8c13f91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007ff3a8de6038 R14: 00007ff3a8de5fa0 R15: 00007ff3a8f0fa28
</TASK>
Add a separate lock just for the tctx_list, tctx_lock. This can nest
under ->uring_lock, where necessary, and be used separately for list
manipulation. For the cancelation off exec side, this removes the
need to grab ->uring_lock, hence fixing the circular locking
dependency.
Reported-by: syzbot+b0e3b77ffaa8a4067ce5@syzkaller.appspotmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
johnhubbard
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Jan 18, 2026
After rename exchanging (either with the rename exchange operation or regular renames in multiple non-atomic steps) two inodes and at least one of them is a directory, we can end up with a log tree that contains only of the inodes and after a power failure that can result in an attempt to delete the other inode when it should not because it was not deleted before the power failure. In some case that delete attempt fails when the target inode is a directory that contains a subvolume inside it, since the log replay code is not prepared to deal with directory entries that point to root items (only inode items). 1) We have directories "dir1" (inode A) and "dir2" (inode B) under the same parent directory; 2) We have a file (inode C) under directory "dir1" (inode A); 3) We have a subvolume inside directory "dir2" (inode B); 4) All these inodes were persisted in a past transaction and we are currently at transaction N; 5) We rename the file (inode C), so at btrfs_log_new_name() we update inode C's last_unlink_trans to N; 6) We get a rename exchange for "dir1" (inode A) and "dir2" (inode B), so after the exchange "dir1" is inode B and "dir2" is inode A. During the rename exchange we call btrfs_log_new_name() for inodes A and B, but because they are directories, we don't update their last_unlink_trans to N; 7) An fsync against the file (inode C) is done, and because its inode has a last_unlink_trans with a value of N we log its parent directory (inode A) (through btrfs_log_all_parents(), called from btrfs_log_inode_parent()). 8) So we end up with inode B not logged, which now has the old name of inode A. At copy_inode_items_to_log(), when logging inode A, we did not check if we had any conflicting inode to log because inode A has a generation lower than the current transaction (created in a past transaction); 9) After a power failure, when replaying the log tree, since we find that inode A has a new name that conflicts with the name of inode B in the fs tree, we attempt to delete inode B... this is wrong since that directory was never deleted before the power failure, and because there is a subvolume inside that directory, attempting to delete it will fail since replay_dir_deletes() and btrfs_unlink_inode() are not prepared to deal with dir items that point to roots instead of inodes. When that happens the mount fails and we get a stack trace like the following: [87.2314] BTRFS info (device dm-0): start tree-log replay [87.2318] BTRFS critical (device dm-0): failed to delete reference to subvol, root 5 inode 256 parent 259 [87.2332] ------------[ cut here ]------------ [87.2338] BTRFS: Transaction aborted (error -2) [87.2346] WARNING: CPU: 1 PID: 638968 at fs/btrfs/inode.c:4345 __btrfs_unlink_inode+0x416/0x440 [btrfs] [87.2368] Modules linked in: btrfs loop dm_thin_pool (...) [87.2470] CPU: 1 UID: 0 PID: 638968 Comm: mount Tainted: G W 6.18.0-rc7-btrfs-next-218+ #2 PREEMPT(full) [87.2489] Tainted: [W]=WARN [87.2494] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.16.2-0-gea1b7a073390-prebuilt.qemu.org 04/01/2014 [87.2514] RIP: 0010:__btrfs_unlink_inode+0x416/0x440 [btrfs] [87.2538] Code: c0 89 04 24 (...) [87.2568] RSP: 0018:ffffc0e741f4b9b8 EFLAGS: 00010286 [87.2574] RAX: 0000000000000000 RBX: ffff9d3ec8a6cf60 RCX: 0000000000000000 [87.2582] RDX: 0000000000000002 RSI: ffffffff84ab45a1 RDI: 00000000ffffffff [87.2591] RBP: ffff9d3ec8a6ef20 R08: 0000000000000000 R09: ffffc0e741f4b840 [87.2599] R10: ffff9d45dc1fffa8 R11: 0000000000000003 R12: ffff9d3ee26d77e0 [87.2608] R13: ffffc0e741f4ba98 R14: ffff9d4458040800 R15: ffff9d44b6b7ca10 [87.2618] FS: 00007f7b9603a840(0000) GS:ffff9d4658982000(0000) knlGS:0000000000000000 [87.2629] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [87.2637] CR2: 00007ffc9ec33b98 CR3: 000000011273e003 CR4: 0000000000370ef0 [87.2648] Call Trace: [87.2651] <TASK> [87.2654] btrfs_unlink_inode+0x15/0x40 [btrfs] [87.2661] unlink_inode_for_log_replay+0x27/0xf0 [btrfs] [87.2669] check_item_in_log+0x1ea/0x2c0 [btrfs] [87.2676] replay_dir_deletes+0x16b/0x380 [btrfs] [87.2684] fixup_inode_link_count+0x34b/0x370 [btrfs] [87.2696] fixup_inode_link_counts+0x41/0x160 [btrfs] [87.2703] btrfs_recover_log_trees+0x1ff/0x7c0 [btrfs] [87.2711] ? __pfx_replay_one_buffer+0x10/0x10 [btrfs] [87.2719] open_ctree+0x10bb/0x15f0 [btrfs] [87.2726] btrfs_get_tree.cold+0xb/0x16c [btrfs] [87.2734] ? fscontext_read+0x15c/0x180 [87.2740] ? rw_verify_area+0x50/0x180 [87.2746] vfs_get_tree+0x25/0xd0 [87.2750] vfs_cmd_create+0x59/0xe0 [87.2755] __do_sys_fsconfig+0x4f6/0x6b0 [87.2760] do_syscall_64+0x50/0x1220 [87.2764] entry_SYSCALL_64_after_hwframe+0x76/0x7e [87.2770] RIP: 0033:0x7f7b9625f4aa [87.2775] Code: 73 01 c3 48 (...) [87.2803] RSP: 002b:00007ffc9ec35b08 EFLAGS: 00000246 ORIG_RAX: 00000000000001af [87.2817] RAX: ffffffffffffffda RBX: 0000558bfa91ac20 RCX: 00007f7b9625f4aa [87.2829] RDX: 0000000000000000 RSI: 0000000000000006 RDI: 0000000000000003 [87.2842] RBP: 0000558bfa91b120 R08: 0000000000000000 R09: 0000000000000000 [87.2854] R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 [87.2864] R13: 00007f7b963f1580 R14: 00007f7b963f326c R15: 00007f7b963d8a23 [87.2877] </TASK> [87.2882] ---[ end trace 0000000000000000 ]--- [87.2891] BTRFS: error (device dm-0 state A) in __btrfs_unlink_inode:4345: errno=-2 No such entry [87.2904] BTRFS: error (device dm-0 state EAO) in do_abort_log_replay:191: errno=-2 No such entry [87.2915] BTRFS critical (device dm-0 state EAO): log tree (for root 5) leaf currently being processed (slot 7 key (258 12 257)): [87.2929] BTRFS info (device dm-0 state EAO): leaf 30736384 gen 10 total ptrs 7 free space 15712 owner 18446744073709551610 [87.2929] BTRFS info (device dm-0 state EAO): refs 3 lock_owner 0 current 638968 [87.2929] item 0 key (257 INODE_ITEM 0) itemoff 16123 itemsize 160 [87.2929] inode generation 9 transid 10 size 0 nbytes 0 [87.2929] block group 0 mode 40755 links 1 uid 0 gid 0 [87.2929] rdev 0 sequence 7 flags 0x0 [87.2929] atime 1765464494.678070921 [87.2929] ctime 1765464494.686606513 [87.2929] mtime 1765464494.686606513 [87.2929] otime 1765464494.678070921 [87.2929] item 1 key (257 INODE_REF 256) itemoff 16109 itemsize 14 [87.2929] index 4 name_len 4 [87.2929] item 2 key (257 DIR_LOG_INDEX 2) itemoff 16101 itemsize 8 [87.2929] dir log end 2 [87.2929] item 3 key (257 DIR_LOG_INDEX 3) itemoff 16093 itemsize 8 [87.2929] dir log end 18446744073709551615 [87.2930] item 4 key (257 DIR_INDEX 3) itemoff 16060 itemsize 33 [87.2930] location key (258 1 0) type 1 [87.2930] transid 10 data_len 0 name_len 3 [87.2930] item 5 key (258 INODE_ITEM 0) itemoff 15900 itemsize 160 [87.2930] inode generation 9 transid 10 size 0 nbytes 0 [87.2930] block group 0 mode 100644 links 1 uid 0 gid 0 [87.2930] rdev 0 sequence 2 flags 0x0 [87.2930] atime 1765464494.678456467 [87.2930] ctime 1765464494.686606513 [87.2930] mtime 1765464494.678456467 [87.2930] otime 1765464494.678456467 [87.2930] item 6 key (258 INODE_REF 257) itemoff 15887 itemsize 13 [87.2930] index 3 name_len 3 [87.2930] BTRFS critical (device dm-0 state EAO): log replay failed in unlink_inode_for_log_replay:1045 for root 5, stage 3, with error -2: failed to unlink inode 256 parent dir 259 name subvol root 5 [87.2963] BTRFS: error (device dm-0 state EAO) in btrfs_recover_log_trees:7743: errno=-2 No such entry [87.2981] BTRFS: error (device dm-0 state EAO) in btrfs_replay_log:2083: errno=-2 No such entry (Failed to recover log tr So fix this by changing copy_inode_items_to_log() to always detect if there are conflicting inodes for the ref/extref of the inode being logged even if the inode was created in a past transaction. A test case for fstests will follow soon. CC: stable@vger.kernel.org # 6.1+ Signed-off-by: Filipe Manana <fdmanana@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
johnhubbard
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Jan 18, 2026
…te in qfq_reset `qfq_class->leaf_qdisc->q.qlen > 0` does not imply that the class itself is active. Two qfq_class objects may point to the same leaf_qdisc. This happens when: 1. one QFQ qdisc is attached to the dev as the root qdisc, and 2. another QFQ qdisc is temporarily referenced (e.g., via qdisc_get() / qdisc_put()) and is pending to be destroyed, as in function tc_new_tfilter. When packets are enqueued through the root QFQ qdisc, the shared leaf_qdisc->q.qlen increases. At the same time, the second QFQ qdisc triggers qdisc_put and qdisc_destroy: the qdisc enters qfq_reset() with its own q->q.qlen == 0, but its class's leaf qdisc->q.qlen > 0. Therefore, the qfq_reset would wrongly deactivate an inactive aggregate and trigger a null-deref in qfq_deactivate_agg: [ 0.903172] BUG: kernel NULL pointer dereference, address: 0000000000000000 [ 0.903571] #PF: supervisor write access in kernel mode [ 0.903860] #PF: error_code(0x0002) - not-present page [ 0.904177] PGD 10299b067 P4D 10299b067 PUD 10299c067 PMD 0 [ 0.904502] Oops: Oops: 0002 [#1] SMP NOPTI [ 0.904737] CPU: 0 UID: 0 PID: 135 Comm: exploit Not tainted 6.19.0-rc3+ #2 NONE [ 0.905157] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.17.0-0-gb52ca86e094d-prebuilt.qemu.org 04/01/2014 [ 0.905754] RIP: 0010:qfq_deactivate_agg (include/linux/list.h:992 (discriminator 2) include/linux/list.h:1006 (discriminator 2) net/sched/sch_qfq.c:1367 (discriminator 2) net/sched/sch_qfq.c:1393 (discriminator 2)) [ 0.906046] Code: 0f 84 4d 01 00 00 48 89 70 18 8b 4b 10 48 c7 c2 ff ff ff ff 48 8b 78 08 48 d3 e2 48 21 f2 48 2b 13 48 8b 30 48 d3 ea 8b 4b 18 0 Code starting with the faulting instruction =========================================== 0: 0f 84 4d 01 00 00 je 0x153 6: 48 89 70 18 mov %rsi,0x18(%rax) a: 8b 4b 10 mov 0x10(%rbx),%ecx d: 48 c7 c2 ff ff ff ff mov $0xffffffffffffffff,%rdx 14: 48 8b 78 08 mov 0x8(%rax),%rdi 18: 48 d3 e2 shl %cl,%rdx 1b: 48 21 f2 and %rsi,%rdx 1e: 48 2b 13 sub (%rbx),%rdx 21: 48 8b 30 mov (%rax),%rsi 24: 48 d3 ea shr %cl,%rdx 27: 8b 4b 18 mov 0x18(%rbx),%ecx ... [ 0.907095] RSP: 0018:ffffc900004a39a0 EFLAGS: 00010246 [ 0.907368] RAX: ffff8881043a0880 RBX: ffff888102953340 RCX: 0000000000000000 [ 0.907723] RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000 [ 0.908100] RBP: ffff888102952180 R08: 0000000000000000 R09: 0000000000000000 [ 0.908451] R10: ffff8881043a0000 R11: 0000000000000000 R12: ffff888102952000 [ 0.908804] R13: ffff888102952180 R14: ffff8881043a0ad8 R15: ffff8881043a0880 [ 0.909179] FS: 000000002a1a0380(0000) GS:ffff888196d8d000(0000) knlGS:0000000000000000 [ 0.909572] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 0.909857] CR2: 0000000000000000 CR3: 0000000102993002 CR4: 0000000000772ef0 [ 0.910247] PKRU: 55555554 [ 0.910391] Call Trace: [ 0.910527] <TASK> [ 0.910638] qfq_reset_qdisc (net/sched/sch_qfq.c:357 net/sched/sch_qfq.c:1485) [ 0.910826] qdisc_reset (include/linux/skbuff.h:2195 include/linux/skbuff.h:2501 include/linux/skbuff.h:3424 include/linux/skbuff.h:3430 net/sched/sch_generic.c:1036) [ 0.911040] __qdisc_destroy (net/sched/sch_generic.c:1076) [ 0.911236] tc_new_tfilter (net/sched/cls_api.c:2447) [ 0.911447] rtnetlink_rcv_msg (net/core/rtnetlink.c:6958) [ 0.911663] ? __pfx_rtnetlink_rcv_msg (net/core/rtnetlink.c:6861) [ 0.911894] netlink_rcv_skb (net/netlink/af_netlink.c:2550) [ 0.912100] netlink_unicast (net/netlink/af_netlink.c:1319 net/netlink/af_netlink.c:1344) [ 0.912296] ? __alloc_skb (net/core/skbuff.c:706) [ 0.912484] netlink_sendmsg (net/netlink/af_netlink.c:1894) [ 0.912682] sock_write_iter (net/socket.c:727 (discriminator 1) net/socket.c:742 (discriminator 1) net/socket.c:1195 (discriminator 1)) [ 0.912880] vfs_write (fs/read_write.c:593 fs/read_write.c:686) [ 0.913077] ksys_write (fs/read_write.c:738) [ 0.913252] do_syscall_64 (arch/x86/entry/syscall_64.c:63 (discriminator 1) arch/x86/entry/syscall_64.c:94 (discriminator 1)) [ 0.913438] entry_SYSCALL_64_after_hwframe (arch/x86/entry/entry_64.S:131) [ 0.913687] RIP: 0033:0x424c34 [ 0.913844] Code: 89 02 48 c7 c0 ff ff ff ff eb bd 66 2e 0f 1f 84 00 00 00 00 00 90 f3 0f 1e fa 80 3d 2d 44 09 00 00 74 13 b8 01 00 00 00 0f 05 9 Code starting with the faulting instruction =========================================== 0: 89 02 mov %eax,(%rdx) 2: 48 c7 c0 ff ff ff ff mov $0xffffffffffffffff,%rax 9: eb bd jmp 0xffffffffffffffc8 b: 66 2e 0f 1f 84 00 00 cs nopw 0x0(%rax,%rax,1) 12: 00 00 00 15: 90 nop 16: f3 0f 1e fa endbr64 1a: 80 3d 2d 44 09 00 00 cmpb $0x0,0x9442d(%rip) # 0x9444e 21: 74 13 je 0x36 23: b8 01 00 00 00 mov $0x1,%eax 28: 0f 05 syscall 2a: 09 .byte 0x9 [ 0.914807] RSP: 002b:00007ffea1938b78 EFLAGS: 00000202 ORIG_RAX: 0000000000000001 [ 0.915197] RAX: ffffffffffffffda RBX: 0000000000000001 RCX: 0000000000424c34 [ 0.915556] RDX: 000000000000003c RSI: 000000002af378c0 RDI: 0000000000000003 [ 0.915912] RBP: 00007ffea1938bc0 R08: 00000000004b8820 R09: 0000000000000000 [ 0.916297] R10: 0000000000000001 R11: 0000000000000202 R12: 00007ffea1938d28 [ 0.916652] R13: 00007ffea1938d38 R14: 00000000004b3828 R15: 0000000000000001 [ 0.917039] </TASK> [ 0.917158] Modules linked in: [ 0.917316] CR2: 0000000000000000 [ 0.917484] ---[ end trace 0000000000000000 ]--- [ 0.917717] RIP: 0010:qfq_deactivate_agg (include/linux/list.h:992 (discriminator 2) include/linux/list.h:1006 (discriminator 2) net/sched/sch_qfq.c:1367 (discriminator 2) net/sched/sch_qfq.c:1393 (discriminator 2)) [ 0.917978] Code: 0f 84 4d 01 00 00 48 89 70 18 8b 4b 10 48 c7 c2 ff ff ff ff 48 8b 78 08 48 d3 e2 48 21 f2 48 2b 13 48 8b 30 48 d3 ea 8b 4b 18 0 Code starting with the faulting instruction =========================================== 0: 0f 84 4d 01 00 00 je 0x153 6: 48 89 70 18 mov %rsi,0x18(%rax) a: 8b 4b 10 mov 0x10(%rbx),%ecx d: 48 c7 c2 ff ff ff ff mov $0xffffffffffffffff,%rdx 14: 48 8b 78 08 mov 0x8(%rax),%rdi 18: 48 d3 e2 shl %cl,%rdx 1b: 48 21 f2 and %rsi,%rdx 1e: 48 2b 13 sub (%rbx),%rdx 21: 48 8b 30 mov (%rax),%rsi 24: 48 d3 ea shr %cl,%rdx 27: 8b 4b 18 mov 0x18(%rbx),%ecx ... [ 0.918902] RSP: 0018:ffffc900004a39a0 EFLAGS: 00010246 [ 0.919198] RAX: ffff8881043a0880 RBX: ffff888102953340 RCX: 0000000000000000 [ 0.919559] RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000 [ 0.919908] RBP: ffff888102952180 R08: 0000000000000000 R09: 0000000000000000 [ 0.920289] R10: ffff8881043a0000 R11: 0000000000000000 R12: ffff888102952000 [ 0.920648] R13: ffff888102952180 R14: ffff8881043a0ad8 R15: ffff8881043a0880 [ 0.921014] FS: 000000002a1a0380(0000) GS:ffff888196d8d000(0000) knlGS:0000000000000000 [ 0.921424] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 0.921710] CR2: 0000000000000000 CR3: 0000000102993002 CR4: 0000000000772ef0 [ 0.922097] PKRU: 55555554 [ 0.922240] Kernel panic - not syncing: Fatal exception [ 0.922590] Kernel Offset: disabled Fixes: 0545a30 ("pkt_sched: QFQ - quick fair queue scheduler") Signed-off-by: Xiang Mei <xmei5@asu.edu> Link: https://patch.msgid.link/20260106034100.1780779-1-xmei5@asu.edu Signed-off-by: Jakub Kicinski <kuba@kernel.org>
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The GPIO controller is configured as non-sleeping but it uses generic
pinctrl helpers which use a mutex for synchronization.
This can cause the following lockdep splat with shared GPIOs enabled on
boards which have multiple devices using the same GPIO:
BUG: sleeping function called from invalid context at
kernel/locking/mutex.c:591
in_atomic(): 1, irqs_disabled(): 1, non_block: 0, pid: 12, name:
kworker/u16:0
preempt_count: 1, expected: 0
RCU nest depth: 0, expected: 0
6 locks held by kworker/u16:0/12:
#0: ffff0001f0018d48 ((wq_completion)events_unbound#2){+.+.}-{0:0},
at: process_one_work+0x18c/0x604
#1: ffff8000842dbdf0 (deferred_probe_work){+.+.}-{0:0}, at:
process_one_work+0x1b4/0x604
#2: ffff0001f18498f8 (&dev->mutex){....}-{4:4}, at:
__device_attach+0x38/0x1b0
#3: ffff0001f75f1e90 (&gdev->srcu){.+.?}-{0:0}, at:
gpiod_direction_output_raw_commit+0x0/0x360
#4: ffff0001f46e3db8 (&shared_desc->spinlock){....}-{3:3}, at:
gpio_shared_proxy_direction_output+0xd0/0x144 [gpio_shared_proxy]
#5: ffff0001f180ee90 (&gdev->srcu){.+.?}-{0:0}, at:
gpiod_direction_output_raw_commit+0x0/0x360
irq event stamp: 81450
hardirqs last enabled at (81449): [<ffff8000813acba4>]
_raw_spin_unlock_irqrestore+0x74/0x78
hardirqs last disabled at (81450): [<ffff8000813abfb8>]
_raw_spin_lock_irqsave+0x84/0x88
softirqs last enabled at (79616): [<ffff8000811455fc>]
__alloc_skb+0x17c/0x1e8
softirqs last disabled at (79614): [<ffff8000811455fc>]
__alloc_skb+0x17c/0x1e8
CPU: 2 UID: 0 PID: 12 Comm: kworker/u16:0 Not tainted
6.19.0-rc4-next-20260105+ #11975 PREEMPT
Hardware name: Hardkernel ODROID-M1 (DT)
Workqueue: events_unbound deferred_probe_work_func
Call trace:
show_stack+0x18/0x24 (C)
dump_stack_lvl+0x90/0xd0
dump_stack+0x18/0x24
__might_resched+0x144/0x248
__might_sleep+0x48/0x98
__mutex_lock+0x5c/0x894
mutex_lock_nested+0x24/0x30
pinctrl_get_device_gpio_range+0x44/0x128
pinctrl_gpio_direction+0x3c/0xe0
pinctrl_gpio_direction_output+0x14/0x20
rockchip_gpio_direction_output+0xb8/0x19c
gpiochip_direction_output+0x38/0x94
gpiod_direction_output_raw_commit+0x1d8/0x360
gpiod_direction_output_nonotify+0x7c/0x230
gpiod_direction_output+0x34/0xf8
gpio_shared_proxy_direction_output+0xec/0x144 [gpio_shared_proxy]
gpiochip_direction_output+0x38/0x94
gpiod_direction_output_raw_commit+0x1d8/0x360
gpiod_direction_output_nonotify+0x7c/0x230
gpiod_configure_flags+0xbc/0x480
gpiod_find_and_request+0x1a0/0x574
gpiod_get_index+0x58/0x84
devm_gpiod_get_index+0x20/0xb4
devm_gpiod_get_optional+0x18/0x30
rockchip_pcie_probe+0x98/0x380
platform_probe+0x5c/0xac
really_probe+0xbc/0x298
Fixes: 936ee26 ("gpio/rockchip: add driver for rockchip gpio")
Cc: stable@vger.kernel.org
Reported-by: Marek Szyprowski <m.szyprowski@samsung.com>
Closes: https://lore.kernel.org/all/d035fc29-3b03-4cd6-b8ec-001f93540bc6@samsung.com/
Acked-by: Heiko Stuebner <heiko@sntech.de>
Link: https://lore.kernel.org/r/20260106090011.21603-1-bartosz.golaszewski@oss.qualcomm.com
Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@oss.qualcomm.com>
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…ked_inode()
In btrfs_read_locked_inode() we are calling btrfs_init_file_extent_tree()
while holding a path with a read locked leaf from a subvolume tree, and
btrfs_init_file_extent_tree() may do a GFP_KERNEL allocation, which can
trigger reclaim.
This can create a circular lock dependency which lockdep warns about with
the following splat:
[6.1433] ======================================================
[6.1574] WARNING: possible circular locking dependency detected
[6.1583] 6.18.0+ #4 Tainted: G U
[6.1591] ------------------------------------------------------
[6.1599] kswapd0/117 is trying to acquire lock:
[6.1606] ffff8d9b6333c5b8 (&delayed_node->mutex){+.+.}-{3:3}, at: __btrfs_release_delayed_node.part.0+0x39/0x2f0
[6.1625]
but task is already holding lock:
[6.1633] ffffffffa4ab8ce0 (fs_reclaim){+.+.}-{0:0}, at: balance_pgdat+0x195/0xc60
[6.1646]
which lock already depends on the new lock.
[6.1657]
the existing dependency chain (in reverse order) is:
[6.1667]
-> #2 (fs_reclaim){+.+.}-{0:0}:
[6.1677] fs_reclaim_acquire+0x9d/0xd0
[6.1685] __kmalloc_cache_noprof+0x59/0x750
[6.1694] btrfs_init_file_extent_tree+0x90/0x100
[6.1702] btrfs_read_locked_inode+0xc3/0x6b0
[6.1710] btrfs_iget+0xbb/0xf0
[6.1716] btrfs_lookup_dentry+0x3c5/0x8e0
[6.1724] btrfs_lookup+0x12/0x30
[6.1731] lookup_open.isra.0+0x1aa/0x6a0
[6.1739] path_openat+0x5f7/0xc60
[6.1746] do_filp_open+0xd6/0x180
[6.1753] do_sys_openat2+0x8b/0xe0
[6.1760] __x64_sys_openat+0x54/0xa0
[6.1768] do_syscall_64+0x97/0x3e0
[6.1776] entry_SYSCALL_64_after_hwframe+0x76/0x7e
[6.1784]
-> #1 (btrfs-tree-00){++++}-{3:3}:
[6.1794] lock_release+0x127/0x2a0
[6.1801] up_read+0x1b/0x30
[6.1808] btrfs_search_slot+0x8e0/0xff0
[6.1817] btrfs_lookup_inode+0x52/0xd0
[6.1825] __btrfs_update_delayed_inode+0x73/0x520
[6.1833] btrfs_commit_inode_delayed_inode+0x11a/0x120
[6.1842] btrfs_log_inode+0x608/0x1aa0
[6.1849] btrfs_log_inode_parent+0x249/0xf80
[6.1857] btrfs_log_dentry_safe+0x3e/0x60
[6.1865] btrfs_sync_file+0x431/0x690
[6.1872] do_fsync+0x39/0x80
[6.1879] __x64_sys_fsync+0x13/0x20
[6.1887] do_syscall_64+0x97/0x3e0
[6.1894] entry_SYSCALL_64_after_hwframe+0x76/0x7e
[6.1903]
-> #0 (&delayed_node->mutex){+.+.}-{3:3}:
[6.1913] __lock_acquire+0x15e9/0x2820
[6.1920] lock_acquire+0xc9/0x2d0
[6.1927] __mutex_lock+0xcc/0x10a0
[6.1934] __btrfs_release_delayed_node.part.0+0x39/0x2f0
[6.1944] btrfs_evict_inode+0x20b/0x4b0
[6.1952] evict+0x15a/0x2f0
[6.1958] prune_icache_sb+0x91/0xd0
[6.1966] super_cache_scan+0x150/0x1d0
[6.1974] do_shrink_slab+0x155/0x6f0
[6.1981] shrink_slab+0x48e/0x890
[6.1988] shrink_one+0x11a/0x1f0
[6.1995] shrink_node+0xbfd/0x1320
[6.1002] balance_pgdat+0x67f/0xc60
[6.1321] kswapd+0x1dc/0x3e0
[6.1643] kthread+0xff/0x240
[6.1965] ret_from_fork+0x223/0x280
[6.1287] ret_from_fork_asm+0x1a/0x30
[6.1616]
other info that might help us debug this:
[6.1561] Chain exists of:
&delayed_node->mutex --> btrfs-tree-00 --> fs_reclaim
[6.1503] Possible unsafe locking scenario:
[6.1110] CPU0 CPU1
[6.1411] ---- ----
[6.1707] lock(fs_reclaim);
[6.1998] lock(btrfs-tree-00);
[6.1291] lock(fs_reclaim);
[6.1581] lock(&delayed_node->mutex);
[6.1874]
*** DEADLOCK ***
[6.1716] 2 locks held by kswapd0/117:
[6.1999] #0: ffffffffa4ab8ce0 (fs_reclaim){+.+.}-{0:0}, at: balance_pgdat+0x195/0xc60
[6.1294] #1: ffff8d998344b0e0 (&type->s_umount_key#40){++++}- {3:3}, at: super_cache_scan+0x37/0x1d0
[6.1596]
stack backtrace:
[6.1183] CPU: 11 UID: 0 PID: 117 Comm: kswapd0 Tainted: G U 6.18.0+ #4 PREEMPT(lazy)
[6.1185] Tainted: [U]=USER
[6.1186] Hardware name: ASUS System Product Name/PRIME B560M-A AC, BIOS 2001 02/01/2023
[6.1187] Call Trace:
[6.1187] <TASK>
[6.1189] dump_stack_lvl+0x6e/0xa0
[6.1192] print_circular_bug.cold+0x17a/0x1c0
[6.1194] check_noncircular+0x175/0x190
[6.1197] __lock_acquire+0x15e9/0x2820
[6.1200] lock_acquire+0xc9/0x2d0
[6.1201] ? __btrfs_release_delayed_node.part.0+0x39/0x2f0
[6.1204] __mutex_lock+0xcc/0x10a0
[6.1206] ? __btrfs_release_delayed_node.part.0+0x39/0x2f0
[6.1208] ? __btrfs_release_delayed_node.part.0+0x39/0x2f0
[6.1211] ? __btrfs_release_delayed_node.part.0+0x39/0x2f0
[6.1213] __btrfs_release_delayed_node.part.0+0x39/0x2f0
[6.1215] btrfs_evict_inode+0x20b/0x4b0
[6.1217] ? lock_acquire+0xc9/0x2d0
[6.1220] evict+0x15a/0x2f0
[6.1222] prune_icache_sb+0x91/0xd0
[6.1224] super_cache_scan+0x150/0x1d0
[6.1226] do_shrink_slab+0x155/0x6f0
[6.1228] shrink_slab+0x48e/0x890
[6.1229] ? shrink_slab+0x2d2/0x890
[6.1231] shrink_one+0x11a/0x1f0
[6.1234] shrink_node+0xbfd/0x1320
[6.1236] ? shrink_node+0xa2d/0x1320
[6.1236] ? shrink_node+0xbd3/0x1320
[6.1239] ? balance_pgdat+0x67f/0xc60
[6.1239] balance_pgdat+0x67f/0xc60
[6.1241] ? finish_task_switch.isra.0+0xc4/0x2a0
[6.1246] kswapd+0x1dc/0x3e0
[6.1247] ? __pfx_autoremove_wake_function+0x10/0x10
[6.1249] ? __pfx_kswapd+0x10/0x10
[6.1250] kthread+0xff/0x240
[6.1251] ? __pfx_kthread+0x10/0x10
[6.1253] ret_from_fork+0x223/0x280
[6.1255] ? __pfx_kthread+0x10/0x10
[6.1257] ret_from_fork_asm+0x1a/0x30
[6.1260] </TASK>
This is because:
1) The fsync task is holding an inode's delayed node mutex (for a
directory) while calling __btrfs_update_delayed_inode() and that needs
to do a search on the subvolume's btree (therefore read lock some
extent buffers);
2) The lookup task, at btrfs_lookup(), triggered reclaim with the
GFP_KERNEL allocation done by btrfs_init_file_extent_tree() while
holding a read lock on a subvolume leaf;
3) The reclaim triggered kswapd which is doing inode eviction for the
directory inode the fsync task is using as an argument to
btrfs_commit_inode_delayed_inode() - but in that call chain we are
trying to read lock the same leaf that the lookup task is holding
while calling btrfs_init_file_extent_tree() and doing the GFP_KERNEL
allocation.
Fix this by calling btrfs_init_file_extent_tree() after we don't need the
path anymore and release it in btrfs_read_locked_inode().
Reported-by: Thomas Hellström <thomas.hellstrom@linux.intel.com>
Link: https://lore.kernel.org/linux-btrfs/6e55113a22347c3925458a5d840a18401a38b276.camel@linux.intel.com/
Fixes: 8679d26 ("btrfs: initialize inode::file_extent_tree after i_mode has been set")
Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
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When forward-porting Rust Binder to 6.18, I neglected to take commit fb56fdf ("mm/list_lru: split the lock to per-cgroup scope") into account, and apparently I did not end up running the shrinker callback when I sanity tested the driver before submission. This leads to crashes like the following: ============================================ WARNING: possible recursive locking detected 6.18.0-mainline-maybe-dirty #1 Tainted: G IO -------------------------------------------- kswapd0/68 is trying to acquire lock: ffff956000fa18b0 (&l->lock){+.+.}-{2:2}, at: lock_list_lru_of_memcg+0x128/0x230 but task is already holding lock: ffff956000fa18b0 (&l->lock){+.+.}-{2:2}, at: rust_helper_spin_lock+0xd/0x20 other info that might help us debug this: Possible unsafe locking scenario: CPU0 ---- lock(&l->lock); lock(&l->lock); *** DEADLOCK *** May be due to missing lock nesting notation 3 locks held by kswapd0/68: #0: ffffffff90d2e260 (fs_reclaim){+.+.}-{0:0}, at: kswapd+0x597/0x1160 #1: ffff956000fa18b0 (&l->lock){+.+.}-{2:2}, at: rust_helper_spin_lock+0xd/0x20 #2: ffffffff90cf3680 (rcu_read_lock){....}-{1:2}, at: lock_list_lru_of_memcg+0x2d/0x230 To fix this, remove the spin_lock() call from rust_shrink_free_page(). Cc: stable <stable@kernel.org> Fixes: eafedbc ("rust_binder: add Rust Binder driver") Signed-off-by: Alice Ryhl <aliceryhl@google.com> Link: https://patch.msgid.link/20251202-binder-shrink-unspin-v1-1-263efb9ad625@google.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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During device unmapping (triggered by module unload or explicit unmap), a refcount underflow occurs causing a use-after-free warning: [14747.574913] ------------[ cut here ]------------ [14747.574916] refcount_t: underflow; use-after-free. [14747.574917] WARNING: lib/refcount.c:28 at refcount_warn_saturate+0x55/0x90, CPU#9: kworker/9:1/378 [14747.574924] Modules linked in: rnbd_client(-) rtrs_client rnbd_server rtrs_server rtrs_core ... [14747.574998] CPU: 9 UID: 0 PID: 378 Comm: kworker/9:1 Tainted: G O N 6.19.0-rc3lblk-fnext+ torvalds#42 PREEMPT(voluntary) [14747.575005] Workqueue: rnbd_clt_wq unmap_device_work [rnbd_client] [14747.575010] RIP: 0010:refcount_warn_saturate+0x55/0x90 [14747.575037] Call Trace: [14747.575038] <TASK> [14747.575038] rnbd_clt_unmap_device+0x170/0x1d0 [rnbd_client] [14747.575044] process_one_work+0x211/0x600 [14747.575052] worker_thread+0x184/0x330 [14747.575055] ? __pfx_worker_thread+0x10/0x10 [14747.575058] kthread+0x10d/0x250 [14747.575062] ? __pfx_kthread+0x10/0x10 [14747.575066] ret_from_fork+0x319/0x390 [14747.575069] ? __pfx_kthread+0x10/0x10 [14747.575072] ret_from_fork_asm+0x1a/0x30 [14747.575083] </TASK> [14747.575096] ---[ end trace 0000000000000000 ]--- Befor this patch :- The bug is a double kobject_put() on dev->kobj during device cleanup. Kobject Lifecycle: kobject_init_and_add() sets kobj.kref = 1 (initialization) kobject_put() sets kobj.kref = 0 (should be called once) * Before this patch: rnbd_clt_unmap_device() rnbd_destroy_sysfs() kobject_del(&dev->kobj) [remove from sysfs] kobject_put(&dev->kobj) PUT #1 (WRONG!) kref: 1 to 0 rnbd_dev_release() kfree(dev) [DEVICE FREED!] rnbd_destroy_gen_disk() [use-after-free!] rnbd_clt_put_dev() refcount_dec_and_test(&dev->refcount) kobject_put(&dev->kobj) PUT #2 (UNDERFLOW!) kref: 0 to -1 [WARNING!] The first kobject_put() in rnbd_destroy_sysfs() prematurely frees the device via rnbd_dev_release(), then the second kobject_put() in rnbd_clt_put_dev() causes refcount underflow. * After this patch :- Remove kobject_put() from rnbd_destroy_sysfs(). This function should only remove sysfs visibility (kobject_del), not manage object lifetime. Call Graph (FIXED): rnbd_clt_unmap_device() rnbd_destroy_sysfs() kobject_del(&dev->kobj) [remove from sysfs only] [kref unchanged: 1] rnbd_destroy_gen_disk() [device still valid] rnbd_clt_put_dev() refcount_dec_and_test(&dev->refcount) kobject_put(&dev->kobj) ONLY PUT (CORRECT!) kref: 1 to 0 [BALANCED] rnbd_dev_release() kfree(dev) [CLEAN DESTRUCTION] This follows the kernel pattern where sysfs removal (kobject_del) is separate from object destruction (kobject_put). Fixes: 581cf83 ("block: rnbd: add .release to rnbd_dev_ktype") Signed-off-by: Chaitanya Kulkarni <ckulkarnilinux@gmail.com> Acked-by: Jack Wang <jinpu.wang@ionos.com> Reviewed-by: Jack Wang <jinpu.wang@ionos.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
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Patch series "mm/hugetlb: fixes for PMD table sharing (incl. using mmu_gather)", v3. One functional fix, one performance regression fix, and two related comment fixes. I cleaned up my prototype I recently shared [1] for the performance fix, deferring most of the cleanups I had in the prototype to a later point. While doing that I identified the other things. The goal of this patch set is to be backported to stable trees "fairly" easily. At least patch #1 and #4. Patch #1 fixes hugetlb_pmd_shared() not detecting any sharing Patch #2 + #3 are simple comment fixes that patch #4 interacts with. Patch #4 is a fix for the reported performance regression due to excessive IPI broadcasts during fork()+exit(). The last patch is all about TLB flushes, IPIs and mmu_gather. Read: complicated There are plenty of cleanups in the future to be had + one reasonable optimization on x86. But that's all out of scope for this series. Runtime tested, with a focus on fixing the performance regression using the original reproducer [2] on x86. This patch (of 4): We switched from (wrongly) using the page count to an independent shared count. Now, shared page tables have a refcount of 1 (excluding speculative references) and instead use ptdesc->pt_share_count to identify sharing. We didn't convert hugetlb_pmd_shared(), so right now, we would never detect a shared PMD table as such, because sharing/unsharing no longer touches the refcount of a PMD table. Page migration, like mbind() or migrate_pages() would allow for migrating folios mapped into such shared PMD tables, even though the folios are not exclusive. In smaps we would account them as "private" although they are "shared", and we would be wrongly setting the PM_MMAP_EXCLUSIVE in the pagemap interface. Fix it by properly using ptdesc_pmd_is_shared() in hugetlb_pmd_shared(). Link: https://lkml.kernel.org/r/20251223214037.580860-1-david@kernel.org Link: https://lkml.kernel.org/r/20251223214037.580860-2-david@kernel.org Link: https://lore.kernel.org/all/8cab934d-4a56-44aa-b641-bfd7e23bd673@kernel.org/ [1] Link: https://lore.kernel.org/all/8cab934d-4a56-44aa-b641-bfd7e23bd673@kernel.org/ [2] Fixes: 59d9094 ("mm: hugetlb: independent PMD page table shared count") Signed-off-by: David Hildenbrand (Red Hat) <david@kernel.org> Reviewed-by: Rik van Riel <riel@surriel.com> Reviewed-by: Lance Yang <lance.yang@linux.dev> Tested-by: Lance Yang <lance.yang@linux.dev> Reviewed-by: Harry Yoo <harry.yoo@oracle.com> Tested-by: Laurence Oberman <loberman@redhat.com> Reviewed-by: Lorenzo Stoakes <lorenzo.stoakes@oracle.com> Acked-by: Oscar Salvador <osalvador@suse.de> Cc: Liu Shixin <liushixin2@huawei.com> Cc: Uschakow, Stanislav" <suschako@amazon.de> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
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A null-ptr-deref was reported in the SCTP transmit path when SCTP-AUTH key initialization fails: ================================================================== KASAN: null-ptr-deref in range [0x0000000000000018-0x000000000000001f] CPU: 0 PID: 16 Comm: ksoftirqd/0 Tainted: G W 6.6.0 #2 RIP: 0010:sctp_packet_bundle_auth net/sctp/output.c:264 [inline] RIP: 0010:sctp_packet_append_chunk+0xb36/0x1260 net/sctp/output.c:401 Call Trace: sctp_packet_transmit_chunk+0x31/0x250 net/sctp/output.c:189 sctp_outq_flush_data+0xa29/0x26d0 net/sctp/outqueue.c:1111 sctp_outq_flush+0xc80/0x1240 net/sctp/outqueue.c:1217 sctp_cmd_interpreter.isra.0+0x19a5/0x62c0 net/sctp/sm_sideeffect.c:1787 sctp_side_effects net/sctp/sm_sideeffect.c:1198 [inline] sctp_do_sm+0x1a3/0x670 net/sctp/sm_sideeffect.c:1169 sctp_assoc_bh_rcv+0x33e/0x640 net/sctp/associola.c:1052 sctp_inq_push+0x1dd/0x280 net/sctp/inqueue.c:88 sctp_rcv+0x11ae/0x3100 net/sctp/input.c:243 sctp6_rcv+0x3d/0x60 net/sctp/ipv6.c:1127 The issue is triggered when sctp_auth_asoc_init_active_key() fails in sctp_sf_do_5_1C_ack() while processing an INIT_ACK. In this case, the command sequence is currently: - SCTP_CMD_PEER_INIT - SCTP_CMD_TIMER_STOP (T1_INIT) - SCTP_CMD_TIMER_START (T1_COOKIE) - SCTP_CMD_NEW_STATE (COOKIE_ECHOED) - SCTP_CMD_ASSOC_SHKEY - SCTP_CMD_GEN_COOKIE_ECHO If SCTP_CMD_ASSOC_SHKEY fails, asoc->shkey remains NULL, while asoc->peer.auth_capable and asoc->peer.peer_chunks have already been set by SCTP_CMD_PEER_INIT. This allows a DATA chunk with auth = 1 and shkey = NULL to be queued by sctp_datamsg_from_user(). Since command interpretation stops on failure, no COOKIE_ECHO should been sent via SCTP_CMD_GEN_COOKIE_ECHO. However, the T1_COOKIE timer has already been started, and it may enqueue a COOKIE_ECHO into the outqueue later. As a result, the DATA chunk can be transmitted together with the COOKIE_ECHO in sctp_outq_flush_data(), leading to the observed issue. Similar to the other places where it calls sctp_auth_asoc_init_active_key() right after sctp_process_init(), this patch moves the SCTP_CMD_ASSOC_SHKEY immediately after SCTP_CMD_PEER_INIT, before stopping T1_INIT and starting T1_COOKIE. This ensures that if shared key generation fails, authenticated DATA cannot be sent. It also allows the T1_INIT timer to retransmit INIT, giving the client another chance to process INIT_ACK and retry key setup. Fixes: 730fc3d ("[SCTP]: Implete SCTP-AUTH parameter processing") Reported-by: Zhen Chen <chenzhen126@huawei.com> Tested-by: Zhen Chen <chenzhen126@huawei.com> Signed-off-by: Xin Long <lucien.xin@gmail.com> Link: https://patch.msgid.link/44881224b375aa8853f5e19b4055a1a56d895813.1768324226.git.lucien.xin@gmail.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
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Jamal Hadi Salim says: ==================== net/sched: teql: Enforce hierarchy placement GangMin Kim <km.kim1503@gmail.com> managed to create a UAF on qfq by inserting teql as a child qdisc and exploiting a qlen sync issue. teql is not intended to be used as a child qdisc. Lets enforce that rule in patch #1. Although patch #1 fixes the issue, we prevent another potential qlen exploit in qfq in patch #2 by enforcing the child's active status is not determined by inspecting the qlen. In patch #3 we add a tdc test case. ==================== Link: https://patch.msgid.link/20260114160243.913069-1-jhs@mojatatu.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
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…itives The "valid" readout delay between the two reads of the watchdog is larger than the valid delta between the resulting watchdog and clocksource intervals, which results in false positive watchdog results. Assume TSC is the clocksource and HPET is the watchdog and both have a uncertainty margin of 250us (default). The watchdog readout does: 1) wdnow = read(HPET); 2) csnow = read(TSC); 3) wdend = read(HPET); The valid window for the delta between #1 and #3 is calculated by the uncertainty margins of the watchdog and the clocksource: m = 2 * watchdog.uncertainty_margin + cs.uncertainty margin; which results in 750us for the TSC/HPET case. The actual interval comparison uses a smaller margin: m = watchdog.uncertainty_margin + cs.uncertainty margin; which results in 500us for the TSC/HPET case. That means the following scenario will trigger the watchdog: Watchdog cycle N: 1) wdnow[N] = read(HPET); 2) csnow[N] = read(TSC); 3) wdend[N] = read(HPET); Assume the delay between #1 and #2 is 100us and the delay between #1 and Watchdog cycle N + 1: 4) wdnow[N + 1] = read(HPET); 5) csnow[N + 1] = read(TSC); 6) wdend[N + 1] = read(HPET); If the delay between #4 and torvalds#6 is within the 750us margin then any delay between #4 and #5 which is larger than 600us will fail the interval check and mark the TSC unstable because the intervals are calculated against the previous value: wd_int = wdnow[N + 1] - wdnow[N]; cs_int = csnow[N + 1] - csnow[N]; Putting the above delays in place this results in: cs_int = (wdnow[N + 1] + 610us) - (wdnow[N] + 100us); -> cs_int = wd_int + 510us; which is obviously larger than the allowed 500us margin and results in marking TSC unstable. Fix this by using the same margin as the interval comparison. If the delay between two watchdog reads is larger than that, then the readout was either disturbed by interconnect congestion, NMIs or SMIs. Fixes: 4ac1dd3 ("clocksource: Set cs_watchdog_read() checks based on .uncertainty_margin") Reported-by: Daniel J Blueman <daniel@quora.org> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Paul E. McKenney <paulmck@kernel.org> Tested-by: Paul E. McKenney <paulmck@kernel.org> Link: https://lore.kernel.org/lkml/20250602223251.496591-1-daniel@quora.org/ Link: https://patch.msgid.link/87bjjxc9dq.ffs@tglx
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When one iio device is a consumer of another, it is possible that
the ->info_exist_lock of both ends up being taken when reading the
value of the consumer device.
Since they currently belong to the same lockdep class (being
initialized in a single location with mutex_init()), that results in a
lockdep warning
CPU0
----
lock(&iio_dev_opaque->info_exist_lock);
lock(&iio_dev_opaque->info_exist_lock);
*** DEADLOCK ***
May be due to missing lock nesting notation
4 locks held by sensors/414:
#0: c31fd6dc (&p->lock){+.+.}-{3:3}, at: seq_read_iter+0x44/0x4e4
#1: c4f5a1c4 (&of->mutex){+.+.}-{3:3}, at: kernfs_seq_start+0x1c/0xac
#2: c2827548 (kn->active#34){.+.+}-{0:0}, at: kernfs_seq_start+0x30/0xac
#3: c1dd2b6 (&iio_dev_opaque->info_exist_lock){+.+.}-{3:3}, at: iio_read_channel_processed_scale+0x24/0xd8
stack backtrace:
CPU: 0 UID: 0 PID: 414 Comm: sensors Not tainted 6.17.11 #5 NONE
Hardware name: Generic AM33XX (Flattened Device Tree)
Call trace:
unwind_backtrace from show_stack+0x10/0x14
show_stack from dump_stack_lvl+0x44/0x60
dump_stack_lvl from print_deadlock_bug+0x2b8/0x334
print_deadlock_bug from __lock_acquire+0x13a4/0x2ab0
__lock_acquire from lock_acquire+0xd0/0x2c0
lock_acquire from __mutex_lock+0xa0/0xe8c
__mutex_lock from mutex_lock_nested+0x1c/0x24
mutex_lock_nested from iio_read_channel_raw+0x20/0x6c
iio_read_channel_raw from rescale_read_raw+0x128/0x1c4
rescale_read_raw from iio_channel_read+0xe4/0xf4
iio_channel_read from iio_read_channel_processed_scale+0x6c/0xd8
iio_read_channel_processed_scale from iio_hwmon_read_val+0x68/0xbc
iio_hwmon_read_val from dev_attr_show+0x18/0x48
dev_attr_show from sysfs_kf_seq_show+0x80/0x110
sysfs_kf_seq_show from seq_read_iter+0xdc/0x4e4
seq_read_iter from vfs_read+0x238/0x2e4
vfs_read from ksys_read+0x6c/0xec
ksys_read from ret_fast_syscall+0x0/0x1c
Just as the mlock_key already has its own lockdep class, add a
lock_class_key for the info_exist mutex.
Note that this has in theory been a problem since before IIO first
left staging, but it only occurs when a chain of consumers is in use
and that is not often done.
Fixes: ac917a8 ("staging:iio:core set the iio_dev.info pointer to null on unregister under lock.")
Signed-off-by: Rasmus Villemoes <ravi@prevas.dk>
Reviewed-by: Peter Rosin <peda@axentia.se>
Cc: <stable@vger.kernel.org>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
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Since the commit 25c6a5a ("net: phy: micrel: Dynamically control external clock of KSZ PHY"), the clock of Micrel PHY has been enabled by phy_driver::resume() and disabled by phy_driver::suspend(). However, devm_clk_get_optional_enabled() is used in kszphy_probe(), so the clock will automatically be disabled when the device is unbound from the bus. Therefore, this could cause the clock to be disabled twice, resulting in clk driver warnings. For example, this issue can be reproduced on i.MX6ULL platform, and we can see the following logs when removing the FEC MAC drivers. $ echo 2188000.ethernet > /sys/bus/platform/drivers/fec/unbind $ echo 20b4000.ethernet > /sys/bus/platform/drivers/fec/unbind [ 109.758207] ------------[ cut here ]------------ [ 109.758240] WARNING: drivers/clk/clk.c:1188 at clk_core_disable+0xb4/0xd0, CPU#0: sh/639 [ 109.771011] enet2_ref already disabled [ 109.793359] Call trace: [ 109.822006] clk_core_disable from clk_disable+0x28/0x34 [ 109.827340] clk_disable from clk_disable_unprepare+0xc/0x18 [ 109.833029] clk_disable_unprepare from devm_clk_release+0x1c/0x28 [ 109.839241] devm_clk_release from devres_release_all+0x98/0x100 [ 109.845278] devres_release_all from device_unbind_cleanup+0xc/0x70 [ 109.851571] device_unbind_cleanup from device_release_driver_internal+0x1a4/0x1f4 [ 109.859170] device_release_driver_internal from bus_remove_device+0xbc/0xe4 [ 109.866243] bus_remove_device from device_del+0x140/0x458 [ 109.871757] device_del from phy_mdio_device_remove+0xc/0x24 [ 109.877452] phy_mdio_device_remove from mdiobus_unregister+0x40/0xac [ 109.883918] mdiobus_unregister from fec_enet_mii_remove+0x40/0x78 [ 109.890125] fec_enet_mii_remove from fec_drv_remove+0x4c/0x158 [ 109.896076] fec_drv_remove from device_release_driver_internal+0x17c/0x1f4 [ 109.962748] WARNING: drivers/clk/clk.c:1047 at clk_core_unprepare+0xfc/0x13c, CPU#0: sh/639 [ 109.975805] enet2_ref already unprepared [ 110.002866] Call trace: [ 110.031758] clk_core_unprepare from clk_unprepare+0x24/0x2c [ 110.037440] clk_unprepare from devm_clk_release+0x1c/0x28 [ 110.042957] devm_clk_release from devres_release_all+0x98/0x100 [ 110.048989] devres_release_all from device_unbind_cleanup+0xc/0x70 [ 110.055280] device_unbind_cleanup from device_release_driver_internal+0x1a4/0x1f4 [ 110.062877] device_release_driver_internal from bus_remove_device+0xbc/0xe4 [ 110.069950] bus_remove_device from device_del+0x140/0x458 [ 110.075469] device_del from phy_mdio_device_remove+0xc/0x24 [ 110.081165] phy_mdio_device_remove from mdiobus_unregister+0x40/0xac [ 110.087632] mdiobus_unregister from fec_enet_mii_remove+0x40/0x78 [ 110.093836] fec_enet_mii_remove from fec_drv_remove+0x4c/0x158 [ 110.099782] fec_drv_remove from device_release_driver_internal+0x17c/0x1f4 After analyzing the process of removing the FEC driver, as shown below, it can be seen that the clock was disabled twice by the PHY driver. fec_drv_remove() --> fec_enet_close() --> phy_stop() --> phy_suspend() --> kszphy_suspend() #1 The clock is disabled --> fec_enet_mii_remove() --> mdiobus_unregister() --> phy_mdio_device_remove() --> device_del() --> devm_clk_release() #2 The clock is disabled again Therefore, devm_clk_get_optional() is used to fix the above issue. And to avoid the issue mentioned by the commit 9853294 ("net: phy: micrel: use devm_clk_get_optional_enabled for the rmii-ref clock"), the clock is enabled by clk_prepare_enable() to get the correct clock rate. Fixes: 25c6a5a ("net: phy: micrel: Dynamically control external clock of KSZ PHY") Signed-off-by: Wei Fang <wei.fang@nxp.com> Reviewed-by: Maxime Chevallier <maxime.chevallier@bootlin.com> Link: https://patch.msgid.link/20260126081544.983517-1-wei.fang@nxp.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
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…alled from deferred_grow_zone() Commit 3acb913 ("mm/mm_init: use deferred_init_memmap_chunk() in deferred_grow_zone()") made deferred_grow_zone() call deferred_init_memmap_chunk() within a pgdat_resize_lock() critical section with irqs disabled. It did check for irqs_disabled() in deferred_init_memmap_chunk() to avoid calling cond_resched(). For a PREEMPT_RT kernel build, however, spin_lock_irqsave() does not disable interrupt but rcu_read_lock() is called. This leads to the following bug report. BUG: sleeping function called from invalid context at mm/mm_init.c:2091 in_atomic(): 0, irqs_disabled(): 0, non_block: 0, pid: 1, name: swapper/0 preempt_count: 0, expected: 0 RCU nest depth: 1, expected: 0 3 locks held by swapper/0/1: #0: ffff80008471b7a0 (sched_domains_mutex){+.+.}-{4:4}, at: sched_domains_mutex_lock+0x28/0x40 #1: ffff003bdfffef48 (&pgdat->node_size_lock){+.+.}-{3:3}, at: deferred_grow_zone+0x140/0x278 #2: ffff800084acf600 (rcu_read_lock){....}-{1:3}, at: rt_spin_lock+0x1b4/0x408 CPU: 0 UID: 0 PID: 1 Comm: swapper/0 Tainted: G W 6.19.0-rc6-test #1 PREEMPT_{RT,(full) } Tainted: [W]=WARN Call trace: show_stack+0x20/0x38 (C) dump_stack_lvl+0xdc/0xf8 dump_stack+0x1c/0x28 __might_resched+0x384/0x530 deferred_init_memmap_chunk+0x560/0x688 deferred_grow_zone+0x190/0x278 _deferred_grow_zone+0x18/0x30 get_page_from_freelist+0x780/0xf78 __alloc_frozen_pages_noprof+0x1dc/0x348 alloc_slab_page+0x30/0x110 allocate_slab+0x98/0x2a0 new_slab+0x4c/0x80 ___slab_alloc+0x5a4/0x770 __slab_alloc.constprop.0+0x88/0x1e0 __kmalloc_node_noprof+0x2c0/0x598 __sdt_alloc+0x3b8/0x728 build_sched_domains+0xe0/0x1260 sched_init_domains+0x14c/0x1c8 sched_init_smp+0x9c/0x1d0 kernel_init_freeable+0x218/0x358 kernel_init+0x28/0x208 ret_from_fork+0x10/0x20 Fix it adding a new argument to deferred_init_memmap_chunk() to explicitly tell it if cond_resched() is allowed or not instead of relying on some current state information which may vary depending on the exact kernel configuration options that are enabled. Link: https://lkml.kernel.org/r/20260122184343.546627-1-longman@redhat.com Fixes: 3acb913 ("mm/mm_init: use deferred_init_memmap_chunk() in deferred_grow_zone()") Signed-off-by: Waiman Long <longman@redhat.com> Suggested-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Reviewed-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Reviewed-by: Mike Rapoport (Microsoft) <rppt@kernel.org> Cc: David Hildenbrand <david@kernel.org> Cc: "Paul E . McKenney" <paulmck@kernel.org> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Wei Yang <richard.weiyang@gmail.com> Cc: <stable@vger.kernrl.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
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Jan 31, 2026
There was a lockdep warning in sprd_gpio: [ 6.258269][T329@C6] [ BUG: Invalid wait context ] [ 6.258270][T329@C6] 6.18.0-android17-0-g30527ad7aaae-ab00009-4k #1 Tainted: G W OE [ 6.258272][T329@C6] ----------------------------- [ 6.258273][T329@C6] modprobe/329 is trying to lock: [ 6.258275][T329@C6] ffffff8081c91690 (&sprd_gpio->lock){....}-{3:3}, at: sprd_gpio_irq_unmask+0x4c/0xa4 [gpio_sprd] [ 6.258282][T329@C6] other info that might help us debug this: [ 6.258283][T329@C6] context-{5:5} [ 6.258285][T329@C6] 3 locks held by modprobe/329: [ 6.258286][T329@C6] #0: ffffff808baca108 (&dev->mutex){....}-{4:4}, at: __driver_attach+0xc4/0x204 [ 6.258295][T329@C6] #1: ffffff80965e7240 (request_class#4){+.+.}-{4:4}, at: __setup_irq+0x1cc/0x82c [ 6.258304][T329@C6] #2: ffffff80965e70c8 (lock_class#4){....}-{2:2}, at: __setup_irq+0x21c/0x82c [ 6.258313][T329@C6] stack backtrace: [ 6.258314][T329@C6] CPU: 6 UID: 0 PID: 329 Comm: modprobe Tainted: G W OE 6.18.0-android17-0-g30527ad7aaae-ab00009-4k #1 PREEMPT 3ad5b0f45741a16e5838da790706e16ceb6717df [ 6.258316][T329@C6] Tainted: [W]=WARN, [O]=OOT_MODULE, [E]=UNSIGNED_MODULE [ 6.258317][T329@C6] Hardware name: Unisoc UMS9632-base Board (DT) [ 6.258318][T329@C6] Call trace: [ 6.258318][T329@C6] show_stack+0x20/0x30 (C) [ 6.258321][T329@C6] __dump_stack+0x28/0x3c [ 6.258324][T329@C6] dump_stack_lvl+0xac/0xf0 [ 6.258326][T329@C6] dump_stack+0x18/0x3c [ 6.258329][T329@C6] __lock_acquire+0x824/0x2c28 [ 6.258331][T329@C6] lock_acquire+0x148/0x2cc [ 6.258333][T329@C6] _raw_spin_lock_irqsave+0x6c/0xb4 [ 6.258334][T329@C6] sprd_gpio_irq_unmask+0x4c/0xa4 [gpio_sprd 814535e93c6d8e0853c45c02eab0fa88a9da6487] [ 6.258337][T329@C6] irq_startup+0x238/0x350 [ 6.258340][T329@C6] __setup_irq+0x504/0x82c [ 6.258342][T329@C6] request_threaded_irq+0x118/0x184 [ 6.258344][T329@C6] devm_request_threaded_irq+0x94/0x120 [ 6.258347][T329@C6] sc8546_init_irq+0x114/0x170 [sc8546_charger 223586ccafc27439f7db4f95b0c8e6e882349a99] [ 6.258352][T329@C6] sc8546_charger_probe+0x53c/0x5a0 [sc8546_charger 223586ccafc27439f7db4f95b0c8e6e882349a99] [ 6.258358][T329@C6] i2c_device_probe+0x2c8/0x350 [ 6.258361][T329@C6] really_probe+0x1a8/0x46c [ 6.258363][T329@C6] __driver_probe_device+0xa4/0x10c [ 6.258366][T329@C6] driver_probe_device+0x44/0x1b4 [ 6.258369][T329@C6] __driver_attach+0xd0/0x204 [ 6.258371][T329@C6] bus_for_each_dev+0x10c/0x168 [ 6.258373][T329@C6] driver_attach+0x2c/0x3c [ 6.258376][T329@C6] bus_add_driver+0x154/0x29c [ 6.258378][T329@C6] driver_register+0x70/0x10c [ 6.258381][T329@C6] i2c_register_driver+0x48/0xc8 [ 6.258384][T329@C6] init_module+0x28/0xfd8 [sc8546_charger 223586ccafc27439f7db4f95b0c8e6e882349a99] [ 6.258389][T329@C6] do_one_initcall+0x128/0x42c [ 6.258392][T329@C6] do_init_module+0x60/0x254 [ 6.258395][T329@C6] load_module+0x1054/0x1220 [ 6.258397][T329@C6] __arm64_sys_finit_module+0x240/0x35c [ 6.258400][T329@C6] invoke_syscall+0x60/0xec [ 6.258402][T329@C6] el0_svc_common+0xb0/0xe4 [ 6.258405][T329@C6] do_el0_svc+0x24/0x30 [ 6.258407][T329@C6] el0_svc+0x54/0x1c4 [ 6.258409][T329@C6] el0t_64_sync_handler+0x68/0xdc [ 6.258411][T329@C6] el0t_64_sync+0x1c4/0x1c8 This is because the spin_lock would change to rt_mutex in PREEMPT_RT, however the sprd_gpio->lock would use in hard-irq, this is unsafe. So change the spin_lock_t to raw_spin_lock_t to use the spinlock in hard-irq. Signed-off-by: Xuewen Yan <xuewen.yan@unisoc.com> Reviewed-by: Baolin Wang <baolin.wang@linux.alibaba.com> Reviewed-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Link: https://lore.kernel.org/r/20260126094209.9855-1-xuewen.yan@unisoc.com [Bartosz: tweaked the commit message] Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@oss.qualcomm.com>
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Two more commits for Turing support.