Public bug reported: [Impact]
* This problem hard locks up 2 CPUs in a deadlock, and this soft locks up other CPUs as an effect; the system becomes unusable. * This is relatively rare / difficult to hit because it's a corner case in scheduling/load balancing that needs timing with CPU stopper code. And it needs SMP plus _NUMA_ system. (but it can be hit with synthetic test case attached in LP.) * Since SMP plus NUMA usually equals _servers_ it looks like a good idea to prevent this bug / hard lockups / rebooting. * The fix resolves the potential deadlock by removing one of the calls required to deadlock from under the locked code. [Test Case] * There's a synthetic test case to reproduce this problem (although without the stack traces - just a system hang) attached to this LP bug. * It uses kprobes/mdelay/cpu stopper calls to force the code to execute and force the timing/locking condition to occur. * $ sudo insmod kmod-stopper.ko Some dmesg logging occurs, and systems either hangs or not. See examples in comments. [Regression Potential] * These are patches to the cpu stop_machine.c code, and they change a bit how it works; however, there are no upstream fixes for these patches anymore and they are still the top of the 'git log --oneline -- kernel/stop_machine.c' output. * These patches have been verified with the synthetic test case and 'stress-ng --class scheduler --sequential 0' (no regressions) on guest with 2 CPUs and one physical system with 24 CPUs. [Other Info] * The patches are required on Xenial and later. * There are 4 patches for Xenial, and 2 patches pending for Bionic. * All patches are applied from Cosmic onwards. [Original Description] These 2 hard lockups happened all of a sudden in the logs, and many soft lockups occur after them as a fallout. Nov 23 15:48:33 SYSTEM_NAME kernel: [4603802.477086] NMI watchdog: Watchdog detected hard LOCKUP on cpu 10 Nov 23 15:48:33 SYSTEM_NAME kernel: [4603802.483800] Modules linked in: <...> Nov 23 15:48:33 SYSTEM_NAME kernel: [4603802.484066] CPU: 10 PID: 58 Comm: migration/10 Not tainted 4.4.0-116-generic #140~14.04.1-Ubuntu Nov 23 15:48:33 SYSTEM_NAME kernel: [4603802.484068] Hardware name: HP ProLiant DL360 Gen9/ProLiant DL360 Gen9, BIOS P89 02/17/2017 Nov 23 15:48:33 SYSTEM_NAME kernel: [4603802.484070] task: ffff883ff2a76200 ti: ffff883ff2110000 task.ti: ffff883ff2110000 Nov 23 15:48:33 SYSTEM_NAME kernel: [4603802.484071] RIP: 0010:[<ffffffff810c8cb0>] [<ffffffff810c8cb0>] native_queued_spin_lock_slowpath+0x160/0x170 Nov 23 15:48:33 SYSTEM_NAME kernel: [4603802.484079] RSP: 0000:ffff883ff2113c58 EFLAGS: 00000002 Nov 23 15:48:33 SYSTEM_NAME kernel: [4603802.484080] RAX: 0000000000000101 RBX: 0000000000000086 RCX: 0000000000000001 Nov 23 15:48:33 SYSTEM_NAME kernel: [4603802.484081] RDX: 0000000000000101 RSI: 0000000000000001 RDI: ffff881fff991ba8 Nov 23 15:48:33 SYSTEM_NAME kernel: [4603802.484083] RBP: ffff883ff2113c58 R08: 0000000000000101 R09: ffff883ff082e200 Nov 23 15:48:33 SYSTEM_NAME kernel: [4603802.484084] R10: 0000000000002e04 R11: 0000000000002e04 R12: ffff881fff997c60 Nov 23 15:48:33 SYSTEM_NAME kernel: [4603802.484085] R13: ffff881fff991ba8 R14: 0000000000000000 R15: ffff881fff997300 Nov 23 15:48:33 SYSTEM_NAME kernel: [4603802.484087] FS: 0000000000000000(0000) GS:ffff883fff000000(0000) knlGS:0000000000000000 Nov 23 15:48:33 SYSTEM_NAME kernel: [4603802.484088] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 Nov 23 15:48:33 SYSTEM_NAME kernel: [4603802.484090] CR2: 00007f7caaa23020 CR3: 0000001f46740000 CR4: 0000000000160670 Nov 23 15:48:33 SYSTEM_NAME kernel: [4603802.484091] Stack: Nov 23 15:48:33 SYSTEM_NAME kernel: [4603802.484092] ffff883ff2113c68 ffffffff811870eb ffff883ff2113c80 ffffffff81819907 Nov 23 15:48:33 SYSTEM_NAME kernel: [4603802.484094] ffff881fff991ba0 ffff883ff2113cb0 ffffffff8111c600 ffff881fff997300 Nov 23 15:48:33 SYSTEM_NAME kernel: [4603802.484096] ffff881fff997c90 ffff881ff03dd400 0000000000000000 ffff883ff2113cc0 Nov 23 15:48:33 SYSTEM_NAME kernel: [4603802.484098] Call Trace: Nov 23 15:48:33 SYSTEM_NAME kernel: [4603802.484105] [<ffffffff811870eb>] queued_spin_lock_slowpath+0xb/0xf Nov 23 15:48:33 SYSTEM_NAME kernel: [4603802.484109] [<ffffffff81819907>] _raw_spin_lock_irqsave+0x37/0x40 Nov 23 15:48:33 SYSTEM_NAME kernel: [4603802.484113] [<ffffffff8111c600>] cpu_stop_queue_work+0x30/0x80 Nov 23 15:48:33 SYSTEM_NAME kernel: [4603802.484116] [<ffffffff8111ccd0>] stop_one_cpu_nowait+0x30/0x40 Nov 23 15:48:33 SYSTEM_NAME kernel: [4603802.484119] [<ffffffff810bbb5b>] load_balance+0x71b/0x940 Nov 23 15:48:33 SYSTEM_NAME kernel: [4603802.484122] [<ffffffff810bbff5>] pick_next_task_fair+0x275/0x4b0 Nov 23 15:48:33 SYSTEM_NAME kernel: [4603802.484126] [<ffffffff81816166>] __schedule+0x6c6/0x7f0 Nov 23 15:48:33 SYSTEM_NAME kernel: [4603802.484132] [<ffffffff810a2560>] ? sort_range+0x30/0x30 Nov 23 15:48:33 SYSTEM_NAME kernel: [4603802.484134] [<ffffffff818162c5>] schedule+0x35/0x80 Nov 23 15:48:33 SYSTEM_NAME kernel: [4603802.484136] [<ffffffff810a262d>] smpboot_thread_fn+0xcd/0x180 Nov 23 15:48:33 SYSTEM_NAME kernel: [4603802.484139] [<ffffffff8109f138>] kthread+0xd8/0xf0 Nov 23 15:48:33 SYSTEM_NAME kernel: [4603802.484141] [<ffffffff8109f060>] ? kthread_park+0x60/0x60 Nov 23 15:48:33 SYSTEM_NAME kernel: [4603802.484143] [<ffffffff81819ff5>] ret_from_fork+0x55/0x80 Nov 23 15:48:33 SYSTEM_NAME kernel: [4603802.484144] [<ffffffff8109f060>] ? kthread_park+0x60/0x60 Nov 23 15:48:33 SYSTEM_NAME kernel: [4603805.644471] NMI watchdog: Watchdog detected hard LOCKUP on cpu 6 Nov 23 15:48:33 SYSTEM_NAME kernel: [4603805.651086] Modules linked in: <...> Nov 23 15:48:33 SYSTEM_NAME kernel: [4603805.651342] CPU: 6 PID: 204932 Comm: ceph-osd Not tainted 4.4.0-116-generic #140~14.04.1-Ubuntu Nov 23 15:48:33 SYSTEM_NAME kernel: [4603805.651344] Hardware name: HP ProLiant DL360 Gen9/ProLiant DL360 Gen9, BIOS P89 02/17/2017 Nov 23 15:48:33 SYSTEM_NAME kernel: [4603805.651345] task: ffff881ff03dd400 ti: ffff883cda77c000 task.ti: ffff883cda77c000 Nov 23 15:48:33 SYSTEM_NAME kernel: [4603805.651347] RIP: 0010:[<ffffffff810aacb6>] [<ffffffff810aacb6>] try_to_wake_up+0x86/0x3f0 Nov 23 15:48:33 SYSTEM_NAME kernel: [4603805.651353] RSP: 0000:ffff883cda77fa78 EFLAGS: 00000002 Nov 23 15:48:33 SYSTEM_NAME kernel: [4603805.651354] RAX: 0000000000000001 RBX: ffff883ff2a76200 RCX: 0000000000000000 Nov 23 15:48:33 SYSTEM_NAME kernel: [4603805.651355] RDX: 0000000000000001 RSI: 0000000000000003 RDI: ffff883ff2a768d4 Nov 23 15:48:33 SYSTEM_NAME kernel: [4603805.651356] RBP: ffff883cda77fab8 R08: 000000000000000a R09: ffff881ff03dd400 Nov 23 15:48:33 SYSTEM_NAME kernel: [4603805.651357] R10: 0000000000000001 R11: 0000000000000000 R12: 0000000000017300 Nov 23 15:48:33 SYSTEM_NAME kernel: [4603805.651359] R13: ffff883ff2a768d4 R14: 0000000000000046 R15: 0000000000000000 Nov 23 15:48:33 SYSTEM_NAME kernel: [4603805.651360] FS: 00007ff8ecbc9700(0000) GS:ffff881fff980000(0000) knlGS:0000000000000000 Nov 23 15:48:33 SYSTEM_NAME kernel: [4603805.651362] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 Nov 23 15:48:33 SYSTEM_NAME kernel: [4603805.651363] CR2: 0000000014583550 CR3: 0000003d4ac96000 CR4: 0000000000160670 Nov 23 15:48:33 SYSTEM_NAME kernel: [4603805.651364] Stack: Nov 23 15:48:33 SYSTEM_NAME kernel: [4603805.651365] 0000000000000202 ffff883cda77fa98 0000000000000003 0000000000000006 Nov 23 15:48:33 SYSTEM_NAME kernel: [4603805.651368] 000000000000000a ffff883cda77fb70 ffff883fff011ba0 ffff881fff991ba0 Nov 23 15:48:33 SYSTEM_NAME kernel: [4603805.651370] ffff883cda77fac8 ffffffff810ab035 ffff883cda77fbc8 ffffffff8111cc22 Nov 23 15:48:33 SYSTEM_NAME kernel: [4603805.651372] Call Trace: Nov 23 15:48:33 SYSTEM_NAME kernel: [4603805.651375] [<ffffffff810ab035>] wake_up_process+0x15/0x20 Nov 23 15:48:33 SYSTEM_NAME kernel: [4603805.651379] [<ffffffff8111cc22>] stop_two_cpus+0x1b2/0x230 Nov 23 15:48:33 SYSTEM_NAME kernel: [4603805.651382] [<ffffffff8111c650>] ? cpu_stop_queue_work+0x80/0x80 Nov 23 15:48:33 SYSTEM_NAME kernel: [4603805.651384] [<ffffffff810b5d15>] ? dequeue_entity+0x455/0x8a0 Nov 23 15:48:33 SYSTEM_NAME kernel: [4603805.651386] [<ffffffff8111c650>] ? cpu_stop_queue_work+0x80/0x80 Nov 23 15:48:33 SYSTEM_NAME kernel: [4603805.651388] [<ffffffff810aaa70>] ? __migrate_swap_task.part.83+0x80/0x80 Nov 23 15:48:33 SYSTEM_NAME kernel: [4603805.651390] [<ffffffff810ab18e>] migrate_swap+0xae/0x130 Nov 23 15:48:33 SYSTEM_NAME kernel: [4603805.651392] [<ffffffff810b4e44>] task_numa_migrate+0x504/0x930 Nov 23 15:48:33 SYSTEM_NAME kernel: [4603805.651394] [<ffffffff810b52e9>] numa_migrate_preferred+0x79/0x80 Nov 23 15:48:33 SYSTEM_NAME kernel: [4603805.651396] [<ffffffff810b9373>] task_numa_fault+0x923/0xcd0 Nov 23 15:48:33 SYSTEM_NAME kernel: [4603805.651400] [<ffffffff8175e407>] ? tcp_recvmsg+0x6b7/0xbd0 Nov 23 15:48:33 SYSTEM_NAME kernel: [4603805.651404] [<ffffffff811da9be>] ? mpol_misplaced+0x14e/0x190 Nov 23 15:48:33 SYSTEM_NAME kernel: [4603805.651408] [<ffffffff811b7836>] handle_pte_fault+0x5a6/0x1440 Nov 23 15:48:33 SYSTEM_NAME kernel: [4603805.651411] [<ffffffff816f6693>] ? sock_recvmsg+0x43/0x50 Nov 23 15:48:33 SYSTEM_NAME kernel: [4603805.651413] [<ffffffff811b9540>] handle_mm_fault+0x250/0x540 Nov 23 15:48:33 SYSTEM_NAME kernel: [4603805.651417] [<ffffffff81069e1a>] __do_page_fault+0x19a/0x430 Nov 23 15:48:33 SYSTEM_NAME kernel: [4603805.651419] [<ffffffff8106a0d2>] do_page_fault+0x22/0x30 Nov 23 15:48:33 SYSTEM_NAME kernel: [4603805.651423] [<ffffffff8181c5a8>] page_fault+0x28/0x30 ** Affects: linux (Ubuntu) Importance: Undecided Status: Incomplete ** Tags: xenial -- You received this bug notification because you are a member of Kernel Packages, which is subscribed to linux in Ubuntu. https://bugs.launchpad.net/bugs/1821259 Title: Hard lockup in 2 CPUs due to deadlock in cpu_stoppers Status in linux package in Ubuntu: Incomplete Bug description: [Impact] * This problem hard locks up 2 CPUs in a deadlock, and this soft locks up other CPUs as an effect; the system becomes unusable. * This is relatively rare / difficult to hit because it's a corner case in scheduling/load balancing that needs timing with CPU stopper code. And it needs SMP plus _NUMA_ system. (but it can be hit with synthetic test case attached in LP.) * Since SMP plus NUMA usually equals _servers_ it looks like a good idea to prevent this bug / hard lockups / rebooting. * The fix resolves the potential deadlock by removing one of the calls required to deadlock from under the locked code. [Test Case] * There's a synthetic test case to reproduce this problem (although without the stack traces - just a system hang) attached to this LP bug. * It uses kprobes/mdelay/cpu stopper calls to force the code to execute and force the timing/locking condition to occur. * $ sudo insmod kmod-stopper.ko Some dmesg logging occurs, and systems either hangs or not. See examples in comments. [Regression Potential] * These are patches to the cpu stop_machine.c code, and they change a bit how it works; however, there are no upstream fixes for these patches anymore and they are still the top of the 'git log --oneline -- kernel/stop_machine.c' output. * These patches have been verified with the synthetic test case and 'stress-ng --class scheduler --sequential 0' (no regressions) on guest with 2 CPUs and one physical system with 24 CPUs. [Other Info] * The patches are required on Xenial and later. * There are 4 patches for Xenial, and 2 patches pending for Bionic. * All patches are applied from Cosmic onwards. [Original Description] These 2 hard lockups happened all of a sudden in the logs, and many soft lockups occur after them as a fallout. Nov 23 15:48:33 SYSTEM_NAME kernel: [4603802.477086] NMI watchdog: Watchdog detected hard LOCKUP on cpu 10 Nov 23 15:48:33 SYSTEM_NAME kernel: [4603802.483800] Modules linked in: <...> Nov 23 15:48:33 SYSTEM_NAME kernel: [4603802.484066] CPU: 10 PID: 58 Comm: migration/10 Not tainted 4.4.0-116-generic #140~14.04.1-Ubuntu Nov 23 15:48:33 SYSTEM_NAME kernel: [4603802.484068] Hardware name: HP ProLiant DL360 Gen9/ProLiant DL360 Gen9, BIOS P89 02/17/2017 Nov 23 15:48:33 SYSTEM_NAME kernel: [4603802.484070] task: ffff883ff2a76200 ti: ffff883ff2110000 task.ti: ffff883ff2110000 Nov 23 15:48:33 SYSTEM_NAME kernel: [4603802.484071] RIP: 0010:[<ffffffff810c8cb0>] [<ffffffff810c8cb0>] native_queued_spin_lock_slowpath+0x160/0x170 Nov 23 15:48:33 SYSTEM_NAME kernel: [4603802.484079] RSP: 0000:ffff883ff2113c58 EFLAGS: 00000002 Nov 23 15:48:33 SYSTEM_NAME kernel: [4603802.484080] RAX: 0000000000000101 RBX: 0000000000000086 RCX: 0000000000000001 Nov 23 15:48:33 SYSTEM_NAME kernel: [4603802.484081] RDX: 0000000000000101 RSI: 0000000000000001 RDI: ffff881fff991ba8 Nov 23 15:48:33 SYSTEM_NAME kernel: [4603802.484083] RBP: ffff883ff2113c58 R08: 0000000000000101 R09: ffff883ff082e200 Nov 23 15:48:33 SYSTEM_NAME kernel: [4603802.484084] R10: 0000000000002e04 R11: 0000000000002e04 R12: ffff881fff997c60 Nov 23 15:48:33 SYSTEM_NAME kernel: [4603802.484085] R13: ffff881fff991ba8 R14: 0000000000000000 R15: ffff881fff997300 Nov 23 15:48:33 SYSTEM_NAME kernel: [4603802.484087] FS: 0000000000000000(0000) GS:ffff883fff000000(0000) knlGS:0000000000000000 Nov 23 15:48:33 SYSTEM_NAME kernel: [4603802.484088] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 Nov 23 15:48:33 SYSTEM_NAME kernel: [4603802.484090] CR2: 00007f7caaa23020 CR3: 0000001f46740000 CR4: 0000000000160670 Nov 23 15:48:33 SYSTEM_NAME kernel: [4603802.484091] Stack: Nov 23 15:48:33 SYSTEM_NAME kernel: [4603802.484092] ffff883ff2113c68 ffffffff811870eb ffff883ff2113c80 ffffffff81819907 Nov 23 15:48:33 SYSTEM_NAME kernel: [4603802.484094] ffff881fff991ba0 ffff883ff2113cb0 ffffffff8111c600 ffff881fff997300 Nov 23 15:48:33 SYSTEM_NAME kernel: [4603802.484096] ffff881fff997c90 ffff881ff03dd400 0000000000000000 ffff883ff2113cc0 Nov 23 15:48:33 SYSTEM_NAME kernel: [4603802.484098] Call Trace: Nov 23 15:48:33 SYSTEM_NAME kernel: [4603802.484105] [<ffffffff811870eb>] queued_spin_lock_slowpath+0xb/0xf Nov 23 15:48:33 SYSTEM_NAME kernel: [4603802.484109] [<ffffffff81819907>] _raw_spin_lock_irqsave+0x37/0x40 Nov 23 15:48:33 SYSTEM_NAME kernel: [4603802.484113] [<ffffffff8111c600>] cpu_stop_queue_work+0x30/0x80 Nov 23 15:48:33 SYSTEM_NAME kernel: [4603802.484116] [<ffffffff8111ccd0>] stop_one_cpu_nowait+0x30/0x40 Nov 23 15:48:33 SYSTEM_NAME kernel: [4603802.484119] [<ffffffff810bbb5b>] load_balance+0x71b/0x940 Nov 23 15:48:33 SYSTEM_NAME kernel: [4603802.484122] [<ffffffff810bbff5>] pick_next_task_fair+0x275/0x4b0 Nov 23 15:48:33 SYSTEM_NAME kernel: [4603802.484126] [<ffffffff81816166>] __schedule+0x6c6/0x7f0 Nov 23 15:48:33 SYSTEM_NAME kernel: [4603802.484132] [<ffffffff810a2560>] ? sort_range+0x30/0x30 Nov 23 15:48:33 SYSTEM_NAME kernel: [4603802.484134] [<ffffffff818162c5>] schedule+0x35/0x80 Nov 23 15:48:33 SYSTEM_NAME kernel: [4603802.484136] [<ffffffff810a262d>] smpboot_thread_fn+0xcd/0x180 Nov 23 15:48:33 SYSTEM_NAME kernel: [4603802.484139] [<ffffffff8109f138>] kthread+0xd8/0xf0 Nov 23 15:48:33 SYSTEM_NAME kernel: [4603802.484141] [<ffffffff8109f060>] ? kthread_park+0x60/0x60 Nov 23 15:48:33 SYSTEM_NAME kernel: [4603802.484143] [<ffffffff81819ff5>] ret_from_fork+0x55/0x80 Nov 23 15:48:33 SYSTEM_NAME kernel: [4603802.484144] [<ffffffff8109f060>] ? kthread_park+0x60/0x60 Nov 23 15:48:33 SYSTEM_NAME kernel: [4603805.644471] NMI watchdog: Watchdog detected hard LOCKUP on cpu 6 Nov 23 15:48:33 SYSTEM_NAME kernel: [4603805.651086] Modules linked in: <...> Nov 23 15:48:33 SYSTEM_NAME kernel: [4603805.651342] CPU: 6 PID: 204932 Comm: ceph-osd Not tainted 4.4.0-116-generic #140~14.04.1-Ubuntu Nov 23 15:48:33 SYSTEM_NAME kernel: [4603805.651344] Hardware name: HP ProLiant DL360 Gen9/ProLiant DL360 Gen9, BIOS P89 02/17/2017 Nov 23 15:48:33 SYSTEM_NAME kernel: [4603805.651345] task: ffff881ff03dd400 ti: ffff883cda77c000 task.ti: ffff883cda77c000 Nov 23 15:48:33 SYSTEM_NAME kernel: [4603805.651347] RIP: 0010:[<ffffffff810aacb6>] [<ffffffff810aacb6>] try_to_wake_up+0x86/0x3f0 Nov 23 15:48:33 SYSTEM_NAME kernel: [4603805.651353] RSP: 0000:ffff883cda77fa78 EFLAGS: 00000002 Nov 23 15:48:33 SYSTEM_NAME kernel: [4603805.651354] RAX: 0000000000000001 RBX: ffff883ff2a76200 RCX: 0000000000000000 Nov 23 15:48:33 SYSTEM_NAME kernel: [4603805.651355] RDX: 0000000000000001 RSI: 0000000000000003 RDI: ffff883ff2a768d4 Nov 23 15:48:33 SYSTEM_NAME kernel: [4603805.651356] RBP: ffff883cda77fab8 R08: 000000000000000a R09: ffff881ff03dd400 Nov 23 15:48:33 SYSTEM_NAME kernel: [4603805.651357] R10: 0000000000000001 R11: 0000000000000000 R12: 0000000000017300 Nov 23 15:48:33 SYSTEM_NAME kernel: [4603805.651359] R13: ffff883ff2a768d4 R14: 0000000000000046 R15: 0000000000000000 Nov 23 15:48:33 SYSTEM_NAME kernel: [4603805.651360] FS: 00007ff8ecbc9700(0000) GS:ffff881fff980000(0000) knlGS:0000000000000000 Nov 23 15:48:33 SYSTEM_NAME kernel: [4603805.651362] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 Nov 23 15:48:33 SYSTEM_NAME kernel: [4603805.651363] CR2: 0000000014583550 CR3: 0000003d4ac96000 CR4: 0000000000160670 Nov 23 15:48:33 SYSTEM_NAME kernel: [4603805.651364] Stack: Nov 23 15:48:33 SYSTEM_NAME kernel: [4603805.651365] 0000000000000202 ffff883cda77fa98 0000000000000003 0000000000000006 Nov 23 15:48:33 SYSTEM_NAME kernel: [4603805.651368] 000000000000000a ffff883cda77fb70 ffff883fff011ba0 ffff881fff991ba0 Nov 23 15:48:33 SYSTEM_NAME kernel: [4603805.651370] ffff883cda77fac8 ffffffff810ab035 ffff883cda77fbc8 ffffffff8111cc22 Nov 23 15:48:33 SYSTEM_NAME kernel: [4603805.651372] Call Trace: Nov 23 15:48:33 SYSTEM_NAME kernel: [4603805.651375] [<ffffffff810ab035>] wake_up_process+0x15/0x20 Nov 23 15:48:33 SYSTEM_NAME kernel: [4603805.651379] [<ffffffff8111cc22>] stop_two_cpus+0x1b2/0x230 Nov 23 15:48:33 SYSTEM_NAME kernel: [4603805.651382] [<ffffffff8111c650>] ? cpu_stop_queue_work+0x80/0x80 Nov 23 15:48:33 SYSTEM_NAME kernel: [4603805.651384] [<ffffffff810b5d15>] ? dequeue_entity+0x455/0x8a0 Nov 23 15:48:33 SYSTEM_NAME kernel: [4603805.651386] [<ffffffff8111c650>] ? cpu_stop_queue_work+0x80/0x80 Nov 23 15:48:33 SYSTEM_NAME kernel: [4603805.651388] [<ffffffff810aaa70>] ? __migrate_swap_task.part.83+0x80/0x80 Nov 23 15:48:33 SYSTEM_NAME kernel: [4603805.651390] [<ffffffff810ab18e>] migrate_swap+0xae/0x130 Nov 23 15:48:33 SYSTEM_NAME kernel: [4603805.651392] [<ffffffff810b4e44>] task_numa_migrate+0x504/0x930 Nov 23 15:48:33 SYSTEM_NAME kernel: [4603805.651394] [<ffffffff810b52e9>] numa_migrate_preferred+0x79/0x80 Nov 23 15:48:33 SYSTEM_NAME kernel: [4603805.651396] [<ffffffff810b9373>] task_numa_fault+0x923/0xcd0 Nov 23 15:48:33 SYSTEM_NAME kernel: [4603805.651400] [<ffffffff8175e407>] ? tcp_recvmsg+0x6b7/0xbd0 Nov 23 15:48:33 SYSTEM_NAME kernel: [4603805.651404] [<ffffffff811da9be>] ? mpol_misplaced+0x14e/0x190 Nov 23 15:48:33 SYSTEM_NAME kernel: [4603805.651408] [<ffffffff811b7836>] handle_pte_fault+0x5a6/0x1440 Nov 23 15:48:33 SYSTEM_NAME kernel: [4603805.651411] [<ffffffff816f6693>] ? sock_recvmsg+0x43/0x50 Nov 23 15:48:33 SYSTEM_NAME kernel: [4603805.651413] [<ffffffff811b9540>] handle_mm_fault+0x250/0x540 Nov 23 15:48:33 SYSTEM_NAME kernel: [4603805.651417] [<ffffffff81069e1a>] __do_page_fault+0x19a/0x430 Nov 23 15:48:33 SYSTEM_NAME kernel: [4603805.651419] [<ffffffff8106a0d2>] do_page_fault+0x22/0x30 Nov 23 15:48:33 SYSTEM_NAME kernel: [4603805.651423] [<ffffffff8181c5a8>] page_fault+0x28/0x30 To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1821259/+subscriptions -- Mailing list: https://launchpad.net/~kernel-packages Post to : kernel-packages@lists.launchpad.net Unsubscribe : https://launchpad.net/~kernel-packages More help : https://help.launchpad.net/ListHelp