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INFO: rcu detected stall in sys_epoll_pwait

Status: auto-obsoleted due to no activity on 2024/01/28 17:58
Subsystems: kernel
[Documentation on labels]
First crash: 230d, last: 230d
Similar bugs (1)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
linux-6.1 INFO: rcu detected stall in sys_epoll_pwait 2 50d 104d 0/3 upstream: reported on 2024/04/03 16:19

Sample crash report:
rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	0-...0: (2 ticks this GP) idle=b094/1/0x4000000000000000 softirq=80444/80446 fqs=1619
rcu: 	         hardirqs   softirqs   csw/system
rcu: 	 number:        0          0            0
rcu: 	cputime:        0          0            0   ==> 52500(ms)
rcu: 	Tasks blocked on level-0 rcu_node (CPUs 0-1): P16984/1:b..l
rcu: 	(detected by 1, t=10505 jiffies, g=134381, q=143 ncpus=2)
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 PID: 5091 Comm: syz-fuzzer Not tainted 6.7.0-rc3-next-20231129-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 11/10/2023
RIP: 0010:task_irq_context kernel/locking/lockdep.c:4607 [inline]
RIP: 0010:__lock_acquire+0x352/0x3b30 kernel/locking/lockdep.c:5074
Code: 00 00 fc ff df 48 89 f2 48 89 74 24 48 48 c1 ea 03 0f b6 14 02 48 89 f0 83 e0 07 83 c0 03 38 d0 7c 08 84 d2 0f 85 b9 10 00 00 <48> 8b 04 24 49 8d 7e 24 8b 54 24 08 83 b8 a4 0a 00 00 01 44 89 e0
RSP: 0018:ffffc90000007a98 EFLAGS: 00000046
RAX: 0000000000000007 RBX: 0000000000000001 RCX: 0000000000000000
RDX: 0000000000000000 RSI: ffff88802665e3e4 RDI: ffff88802665e430
RBP: 0000000000000000 R08: 0000000000000001 R09: 0000000000000001
R10: 0000000000000005 R11: 0000000000000001 R12: 0000000000000002
R13: 0000000000000000 R14: ffff88802665e428 R15: 0000000000000001
FS:  000000c0083b7490(0000) GS:ffff8880b9800000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000020006000 CR3: 000000007aa97000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <NMI>
 </NMI>
 <IRQ>
 lock_acquire kernel/locking/lockdep.c:5754 [inline]
 lock_acquire+0x1b1/0x530 kernel/locking/lockdep.c:5719
 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline]
 _raw_spin_lock_irqsave+0x3a/0x50 kernel/locking/spinlock.c:162
 debug_object_activate+0x195/0x540 lib/debugobjects.c:708
 debug_hrtimer_activate kernel/time/hrtimer.c:422 [inline]
 debug_activate kernel/time/hrtimer.c:477 [inline]
 enqueue_hrtimer+0x25/0x320 kernel/time/hrtimer.c:1087
 __run_hrtimer kernel/time/hrtimer.c:1705 [inline]
 __hrtimer_run_queues+0xa0f/0xc20 kernel/time/hrtimer.c:1752
 hrtimer_interrupt+0x31b/0x800 kernel/time/hrtimer.c:1814
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1065 [inline]
 __sysvec_apic_timer_interrupt+0x10c/0x410 arch/x86/kernel/apic/apic.c:1082
 sysvec_apic_timer_interrupt+0x90/0xb0 arch/x86/kernel/apic/apic.c:1076
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:645
RIP: 0010:__raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:152 [inline]
RIP: 0010:_raw_spin_unlock_irqrestore+0x31/0x70 kernel/locking/spinlock.c:194
Code: f5 53 48 8b 74 24 10 48 89 fb 48 83 c7 18 e8 06 68 de f6 48 89 df e8 ce df de f6 f7 c5 00 02 00 00 75 1f 9c 58 f6 c4 02 75 2f <bf> 01 00 00 00 e8 c5 89 d0 f6 65 8b 05 26 b3 79 75 85 c0 74 12 5b
RSP: 0018:ffffc9000437fad8 EFLAGS: 00000246
RAX: 0000000000000006 RBX: ffff8880b982b940 RCX: 1ffffffff1e728e9
RDX: 0000000000000000 RSI: ffffffff8accb7a0 RDI: ffffffff8b2f1120
RBP: 0000000000000246 R08: 0000000000000001 R09: 0000000000000001
R10: ffffffff8f3979d7 R11: 0000000000000001 R12: 0000000000000001
R13: ffff8880b982b9c0 R14: 0000000000000000 R15: ffffc9000437fba0
 unlock_hrtimer_base kernel/time/hrtimer.c:1020 [inline]
 hrtimer_try_to_cancel+0x161/0x4d0 kernel/time/hrtimer.c:1339
 hrtimer_cancel kernel/time/hrtimer.c:1446 [inline]
 schedule_hrtimeout_range_clock+0x21c/0x430 kernel/time/hrtimer.c:2310
 ep_poll fs/eventpoll.c:1921 [inline]
 do_epoll_wait+0x1316/0x1a00 fs/eventpoll.c:2318
 do_compat_epoll_pwait.part.0+0x26/0x1d0 fs/eventpoll.c:2352
 do_epoll_pwait fs/eventpoll.c:2359 [inline]
 __do_sys_epoll_pwait fs/eventpoll.c:2365 [inline]
 __se_sys_epoll_pwait fs/eventpoll.c:2359 [inline]
 __x64_sys_epoll_pwait+0x20c/0x320 fs/eventpoll.c:2359
 do_syscall_x64 arch/x86/entry/common.c:51 [inline]
 do_syscall_64+0x40/0x110 arch/x86/entry/common.c:82
 entry_SYSCALL_64_after_hwframe+0x62/0x6a
RIP: 0033:0x403ace
Code: 48 89 6c 24 38 48 8d 6c 24 38 e8 0d 00 00 00 48 8b 6c 24 38 48 83 c4 40 c3 cc cc cc 49 89 f2 48 89 fa 48 89 ce 48 89 df 0f 05 <48> 3d 01 f0 ff ff 76 15 48 f7 d8 48 89 c1 48 c7 c0 ff ff ff ff 48
RSP: 002b:000000c00fc1b778 EFLAGS: 00000246 ORIG_RAX: 0000000000000119
RAX: ffffffffffffffda RBX: 0000000000000004 RCX: 0000000000403ace
RDX: 0000000000000080 RSI: 000000c00fc1b840 RDI: 0000000000000004
RBP: 000000c00fc1b7c0 R08: 0000000000000000 R09: 0000000000000000
R10: 000000000000018b R11: 0000000000000246 R12: 000000c00fc1b850
R13: 0000000000000000 R14: 000000c0038f81a0 R15: 0000000000000001
 </TASK>
task:syz-executor.2  state:R  running task     stack:28400 pid:16984 tgid:16980 ppid:5096   flags:0x00004002
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5399 [inline]
 __schedule+0xf15/0x5c00 kernel/sched/core.c:6726
 preempt_schedule_irq+0x51/0x90 kernel/sched/core.c:7046
 irqentry_exit+0x36/0x80 kernel/entry/common.c:432
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:645
RIP: 0010:write_comp_data+0x34/0x80 kernel/kcov.c:236
Code: 48 8b 15 1f ad 7b 7e 65 8b 05 20 ad 7b 7e a9 00 01 ff 00 74 0f f6 c4 01 74 59 8b 82 fc 15 00 00 85 c0 74 4f 8b 82 d8 15 00 00 <83> f8 03 75 44 48 8b 82 e0 15 00 00 8b 92 dc 15 00 00 48 8b 38 48
RSP: 0018:ffffc9001596f700 EFLAGS: 00000246
RAX: 0000000000000002 RBX: 0000000000000001 RCX: ffffffff81c9024e
RDX: ffff88807bc11dc0 RSI: 0000000000000000 RDI: 0000000000000005
RBP: ffff888037655940 R08: 0000000000000005 R09: 0000000000000000
R10: 0000000000000001 R11: 0000000000000001 R12: 0000000000000017
R13: 0000000000000000 R14: ffff88801fb57310 R15: 0000000000000000
 count_memcg_event_mm.part.0+0x8e/0x340 include/linux/memcontrol.h:1108
 count_memcg_event_mm include/linux/memcontrol.h:573 [inline]
 mm_account_fault mm/memory.c:5221 [inline]
 handle_mm_fault+0x1b8/0xa00 mm/memory.c:5368
 faultin_page mm/gup.c:958 [inline]
 __get_user_pages+0x4b1/0x1490 mm/gup.c:1241
 __get_user_pages_locked mm/gup.c:1509 [inline]
 __gup_longterm_locked+0x278/0x2ab0 mm/gup.c:2211
 pin_user_pages_remote+0xee/0x140 mm/gup.c:3358
 process_vm_rw_single_vec mm/process_vm_access.c:106 [inline]
 process_vm_rw_core.constprop.0+0x439/0xa00 mm/process_vm_access.c:216
 process_vm_rw+0x2fd/0x360 mm/process_vm_access.c:284
 __do_sys_process_vm_readv mm/process_vm_access.c:296 [inline]
 __se_sys_process_vm_readv mm/process_vm_access.c:292 [inline]
 __x64_sys_process_vm_readv+0xe2/0x1b0 mm/process_vm_access.c:292
 do_syscall_x64 arch/x86/entry/common.c:51 [inline]
 do_syscall_64+0x40/0x110 arch/x86/entry/common.c:82
 entry_SYSCALL_64_after_hwframe+0x62/0x6a
RIP: 0033:0x7fd0c987cae9
RSP: 002b:00007fd0ca5e10c8 EFLAGS: 00000246 ORIG_RAX: 0000000000000136
RAX: ffffffffffffffda RBX: 00007fd0c999bf80 RCX: 00007fd0c987cae9
RDX: 0000000000000002 RSI: 0000000020008400 RDI: 0000000000000d0e
RBP: 00007fd0c98c847a R08: 0000000000000286 R09: 0000000000000000
R10: 0000000020008640 R11: 0000000000000246 R12: 0000000000000000
R13: 000000000000000b R14: 00007fd0c999bf80 R15: 00007ffe9ff5fd58
 </TASK>
rcu: rcu_preempt kthread starved for 2410 jiffies! g134381 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x0 ->cpu=1
rcu: 	Unless rcu_preempt kthread gets sufficient CPU time, OOM is now expected behavior.
rcu: RCU grace-period kthread stack dump:
task:rcu_preempt     state:R  running task     stack:27792 pid:17    tgid:17    ppid:2      flags:0x00004000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5399 [inline]
 __schedule+0xf15/0x5c00 kernel/sched/core.c:6726
 __schedule_loop kernel/sched/core.c:6801 [inline]
 schedule+0xe7/0x270 kernel/sched/core.c:6816
 schedule_timeout+0x136/0x290 kernel/time/timer.c:2167
 rcu_gp_fqs_loop+0x1eb/0xb00 kernel/rcu/tree.c:1631
 rcu_gp_kthread+0x245/0x380 kernel/rcu/tree.c:1830
 kthread+0x2c1/0x3a0 kernel/kthread.c:389
 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147
 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:242
 </TASK>
rcu: Stack dump where RCU GP kthread last ran:
CPU: 1 PID: 0 Comm: swapper/1 Not tainted 6.7.0-rc3-next-20231129-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 11/10/2023
RIP: 0010:native_irq_disable arch/x86/include/asm/irqflags.h:37 [inline]
RIP: 0010:arch_local_irq_disable arch/x86/include/asm/irqflags.h:72 [inline]
RIP: 0010:acpi_safe_halt+0x1a/0x20 drivers/acpi/processor_idle.c:113
Code: 08 ed c3 66 66 2e 0f 1f 84 00 00 00 00 00 66 90 65 48 8b 05 08 25 7d 75 48 8b 00 a8 08 75 0c 66 90 0f 00 2d 38 c5 b3 00 fb f4 <fa> c3 0f 1f 40 00 0f b6 47 08 3c 01 74 0b 3c 02 74 05 8b 7f 04 eb
RSP: 0018:ffffc90000187d58 EFLAGS: 00000246
RAX: 0000000000004000 RBX: 0000000000000001 RCX: ffffffff8a867d95
RDX: 0000000000000001 RSI: ffff8880166c9000 RDI: ffff8880166c9064
RBP: ffff8880166c9064 R08: 0000000000000001 R09: ffffed1017326dbd
R10: ffff8880b9936deb R11: 0000000000000000 R12: ffff8880166cf000
R13: ffffffff8dd224a0 R14: 0000000000000001 R15: 0000000000000000
FS:  0000000000000000(0000) GS:ffff8880b9900000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f4d68b76bf8 CR3: 000000002e79e000 CR4: 00000000003506f0
Call Trace:
 <IRQ>
 </IRQ>
 <TASK>
 acpi_idle_enter+0xc5/0x160 drivers/acpi/processor_idle.c:707
 cpuidle_enter_state+0x83/0x500 drivers/cpuidle/cpuidle.c:267
 cpuidle_enter+0x4e/0xa0 drivers/cpuidle/cpuidle.c:388
 cpuidle_idle_call kernel/sched/idle.c:215 [inline]
 do_idle+0x314/0x3f0 kernel/sched/idle.c:312
 cpu_startup_entry+0x4f/0x60 kernel/sched/idle.c:410
 start_secondary+0x20e/0x2a0 arch/x86/kernel/smpboot.c:336
 secondary_startup_64_no_verify+0x166/0x16b
 </TASK>

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2023/11/29 17:53 linux-next 1f5c003694fa 6e78f9ce .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-linux-next-kasan-gce-root INFO: rcu detected stall in sys_epoll_pwait
* Struck through repros no longer work on HEAD.