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INFO: rcu detected stall in sys_poll (3)

Status: auto-closed as invalid on 2022/09/09 03:17
Subsystems: kernel
[Documentation on labels]
First crash: 685d, last: 685d
▶ ▼ Similar bugs (2)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream INFO: rcu detected stall in sys_poll (2) kernel 9 1570d 1570d 0/26 closed as dup on 2020/01/08 06:14
upstream INFO: rcu detected stall in sys_poll kernel 21 1605d 1606d 0/26 closed as invalid on 2019/12/04 14:14

Sample crash report:
rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	1-...!: (1 GPs behind) idle=6ab/1/0x4000000000000000 softirq=277492/277493 fqs=4 
	(detected by 0, t=10502 jiffies, g=386413, q=158 ncpus=2)
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 PID: 12379 Comm: syz-executor.3 Not tainted 5.19.0-rc1-syzkaller-00238-gaa3398fb4b3f #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
RIP: 0010:__preempt_count_add arch/x86/include/asm/preempt.h:80 [inline]
RIP: 0010:rcu_read_lock_sched_notrace include/linux/rcupdate.h:795 [inline]
RIP: 0010:trace_lock_acquire+0x43/0x1d0 include/trace/events/lock.h:24
Code: 08 0f 83 ac 00 00 00 89 d8 c1 e8 06 48 8d 3c c5 68 82 03 8e be 08 00 00 00 e8 e9 bd 72 00 89 d8 48 0f a3 05 37 be 9b 0c 73 47 <65> ff 05 ce aa 9a 7e 48 c7 c0 58 35 f0 8d 48 c1 e8 03 48 b9 00 00
RSP: 0018:ffffc900001f0ab8 EFLAGS: 00000057
RAX: 0000000000000001 RBX: 0000000000000001 RCX: ffffffff8167c427
RDX: 0000000000000000 RSI: 0000000000000008 RDI: ffffffff8e038268
RBP: ffffc900001f0c60 R08: dffffc0000000000 R09: fffffbfff1c0704e
R10: fffffbfff1c0704e R11: 1ffffffff1c0704d R12: dffffc0000000000
R13: 1ffff9200003e168 R14: ffffffff8cb1ebe0 R15: 0000000000000000
FS:  00007f4a01100700(0000) GS:ffff8880b9b00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f49fefbbfc0 CR3: 000000007a42f000 CR4: 00000000003506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <IRQ>
 lock_acquire+0xa5/0x400 kernel/locking/lockdep.c:5636
 rcu_lock_acquire+0x2a/0x30 include/linux/rcupdate.h:269
 rcu_read_lock include/linux/rcupdate.h:695 [inline]
 advance_sched+0x67e/0x8c0 net/sched/sch_taprio.c:768
 __run_hrtimer kernel/time/hrtimer.c:1685 [inline]
 __hrtimer_run_queues+0x50b/0xa60 kernel/time/hrtimer.c:1749
 hrtimer_interrupt+0x3a6/0xfd0 kernel/time/hrtimer.c:1811
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1095 [inline]
 __sysvec_apic_timer_interrupt+0xf9/0x280 arch/x86/kernel/apic/apic.c:1112
 sysvec_apic_timer_interrupt+0x8c/0xb0 arch/x86/kernel/apic/apic.c:1106
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x1b/0x20
RIP: 0010:finish_lock_switch+0x1c5/0x350 kernel/sched/core.c:4877
Code: be ff ff ff ff e8 bb af cc 08 85 c0 74 37 4d 85 e4 75 58 0f 1f 44 00 00 4c 89 ff e8 25 9b d5 08 e8 00 18 30 00 fb 48 83 c4 10 <5b> 41 5c 41 5d 41 5e 41 5f 5d c3 0f 0b 4d 85 e4 0f 85 4a ff ff ff
RSP: 0018:ffffc90006a1f528 EFLAGS: 00000286
RAX: b10c0746f9cc9800 RBX: 1ffff110173674c8 RCX: ffffffff9153de03
RDX: dffffc0000000000 RSI: ffffffff8a8d2140 RDI: ffffffff8ae98a20
RBP: ffff8880b9b3a640 R08: dffffc0000000000 R09: ffffed1017367371
R10: ffffed1017367371 R11: 1ffff11017367370 R12: 0000000000000000
R13: ffff8880b9b3a8d8 R14: dffffc0000000000 R15: ffff8880b9b39b80
 finish_task_switch+0x140/0x610 kernel/sched/core.c:4994
 context_switch kernel/sched/core.c:5119 [inline]
 __schedule+0x95f/0xec0 kernel/sched/core.c:6428
 schedule+0xeb/0x1b0 kernel/sched/core.c:6500
 schedule_hrtimeout_range_clock+0x277/0x470 kernel/time/hrtimer.c:2305
 poll_schedule_timeout+0x10b/0x150 fs/select.c:244
 do_poll fs/select.c:965 [inline]
 do_sys_poll+0x1060/0x1500 fs/select.c:1015
 __do_sys_poll fs/select.c:1080 [inline]
 __se_sys_poll+0x1ec/0x420 fs/select.c:1068
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x2b/0x70 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x46/0xb0
RIP: 0033:0x7f4a00089109
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 b8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f4a01100168 EFLAGS: 00000246 ORIG_RAX: 0000000000000007
RAX: ffffffffffffffda RBX: 00007f4a0019bf60 RCX: 00007f4a00089109
RDX: 00000000000001ff RSI: 0000000000000001 RDI: 0000000020000200
RBP: 00007f4a000e30ad R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007ffdd12ab1ff R14: 00007f4a01100300 R15: 0000000000022000
 </TASK>
rcu: rcu_preempt kthread starved for 10494 jiffies! g386413 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x0 ->cpu=0
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:26232 pid:   17 ppid:     2 flags:0x00004000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5116 [inline]
 __schedule+0x957/0xec0 kernel/sched/core.c:6428
 schedule+0xeb/0x1b0 kernel/sched/core.c:6500
 schedule_timeout+0x1b9/0x300 kernel/time/timer.c:1935
 rcu_gp_fqs_loop+0x2b9/0xfb0 kernel/rcu/tree.c:1999
 rcu_gp_kthread+0xa5/0x360 kernel/rcu/tree.c:2187
 kthread+0x266/0x300 kernel/kthread.c:376
 ret_from_fork+0x1f/0x30
 </TASK>
rcu: Stack dump where RCU GP kthread last ran:
NMI backtrace for cpu 0
CPU: 0 PID: 21193 Comm: kworker/u4:3 Not tainted 5.19.0-rc1-syzkaller-00238-gaa3398fb4b3f #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Workqueue: events_unbound toggle_allocation_gate
Call Trace:
 <IRQ>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0x1e3/0x2cb lib/dump_stack.c:106
 nmi_cpu_backtrace+0x473/0x4a0 lib/nmi_backtrace.c:111
 nmi_trigger_cpumask_backtrace+0x168/0x280 lib/nmi_backtrace.c:62
 trigger_single_cpu_backtrace include/linux/nmi.h:164 [inline]
 rcu_check_gp_kthread_starvation+0x1da/0x250 kernel/rcu/tree_stall.h:518
 print_other_cpu_stall+0x140a/0x1560 kernel/rcu/tree_stall.h:623
 check_cpu_stall kernel/rcu/tree_stall.h:771 [inline]
 rcu_pending kernel/rcu/tree.c:3977 [inline]
 rcu_sched_clock_irq+0x9c4/0x19f0 kernel/rcu/tree.c:2675
 update_process_times+0x148/0x1b0 kernel/time/timer.c:1839
 tick_sched_handle kernel/time/tick-sched.c:243 [inline]
 tick_sched_timer+0x377/0x540 kernel/time/tick-sched.c:1481
 __run_hrtimer kernel/time/hrtimer.c:1685 [inline]
 __hrtimer_run_queues+0x4cb/0xa60 kernel/time/hrtimer.c:1749
 hrtimer_interrupt+0x3a6/0xfd0 kernel/time/hrtimer.c:1811
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1095 [inline]
 __sysvec_apic_timer_interrupt+0xf9/0x280 arch/x86/kernel/apic/apic.c:1112
 sysvec_apic_timer_interrupt+0x8c/0xb0 arch/x86/kernel/apic/apic.c:1106
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x1b/0x20
RIP: 0010:csd_lock_wait kernel/smp.c:414 [inline]
RIP: 0010:smp_call_function_many_cond+0xf12/0x1500 kernel/smp.c:988
Code: 8b 3c 24 44 89 fe 83 e6 01 31 ff e8 08 e2 0a 00 41 83 e7 01 49 bf 00 00 00 00 00 fc ff df 75 08 e8 d3 dd 0a 00 eb 46 90 f3 90 <42> 0f b6 04 3b 84 c0 75 11 41 f7 04 24 01 00 00 00 74 2b e8 b6 dd
RSP: 0018:ffffc9000309f780 EFLAGS: 00000293
RAX: ffffffff817cb8ca RBX: 1ffff11017367d39 RCX: ffff88801ec88000
RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000000
RBP: ffffc9000309f940 R08: ffffffff817cb898 R09: fffffbfff1fa8c01
R10: fffffbfff1fa8c01 R11: 1ffffffff1fa8c00 R12: ffff8880b9b3e9c8
R13: 1ffff11017347588 R14: 0000000000000001 R15: dffffc0000000000
 on_each_cpu_cond_mask+0x3b/0x80 kernel/smp.c:1154
 on_each_cpu include/linux/smp.h:71 [inline]
 text_poke_sync arch/x86/kernel/alternative.c:1231 [inline]
 text_poke_bp_batch+0x324/0x970 arch/x86/kernel/alternative.c:1419
 text_poke_flush arch/x86/kernel/alternative.c:1589 [inline]
 text_poke_finish+0x16/0x30 arch/x86/kernel/alternative.c:1596
 arch_jump_label_transform_apply+0x13/0x20 arch/x86/kernel/jump_label.c:146
 static_key_enable_cpuslocked+0x129/0x250 kernel/jump_label.c:177
 static_key_enable+0x16/0x20 kernel/jump_label.c:190
 toggle_allocation_gate+0xbf/0x470 mm/kfence/core.c:808
 process_one_work+0x81c/0xd10 kernel/workqueue.c:2289
 worker_thread+0xb14/0x1330 kernel/workqueue.c:2436
 kthread+0x266/0x300 kernel/kthread.c:376
 ret_from_fork+0x1f/0x30
 </TASK>
watchdog: BUG: soft lockup - CPU#0 stuck for 246s! [kworker/u4:3:21193]
Modules linked in:
irq event stamp: 86535542
hardirqs last  enabled at (86535541): [<ffffffff8a400c8b>] asm_sysvec_apic_timer_interrupt+0x1b/0x20
hardirqs last disabled at (86535542): [<ffffffff8a2ad16a>] sysvec_apic_timer_interrupt+0xa/0xb0 arch/x86/kernel/apic/apic.c:1106
softirqs last  enabled at (86485712): [<ffffffff81519a5c>] __irq_exit_rcu+0xec/0x170 kernel/softirq.c:650
softirqs last disabled at (86485635): [<ffffffff81519a5c>] __irq_exit_rcu+0xec/0x170 kernel/softirq.c:650
CPU: 0 PID: 21193 Comm: kworker/u4:3 Not tainted 5.19.0-rc1-syzkaller-00238-gaa3398fb4b3f #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Workqueue: events_unbound toggle_allocation_gate
RIP: 0010:get_current arch/x86/include/asm/current.h:15 [inline]
RIP: 0010:__sanitizer_cov_trace_pc+0x4/0x60 kernel/kcov.c:199
Code: 00 00 00 00 66 90 53 48 89 fb e8 17 00 00 00 48 8b 3d 28 ee 7b 0c 48 89 de 5b e9 77 f7 51 00 cc cc cc cc cc cc cc 48 8b 04 24 <65> 48 8b 0c 25 00 6f 02 00 65 8b 15 74 d8 7a 7e f7 c2 00 01 ff 00
RSP: 0018:ffffc9000309f778 EFLAGS: 00000202
RAX: ffffffff817cb8ca RBX: 1ffff11017367d39 RCX: ffff88801ec88000
RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000000
RBP: ffffc9000309f940 R08: ffffffff817cb898 R09: fffffbfff1fa8c01
R10: fffffbfff1fa8c01 R11: 1ffffffff1fa8c00 R12: ffff8880b9b3e9c8
R13: 1ffff11017347588 R14: 0000000000000001 R15: dffffc0000000000
FS:  0000000000000000(0000) GS:ffff8880b9a00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f13a7eda9e8 CR3: 000000000c88e000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 csd_lock_wait kernel/smp.c:414 [inline]
 smp_call_function_many_cond+0xf2a/0x1500 kernel/smp.c:988
 on_each_cpu_cond_mask+0x3b/0x80 kernel/smp.c:1154
 on_each_cpu include/linux/smp.h:71 [inline]
 text_poke_sync arch/x86/kernel/alternative.c:1231 [inline]
 text_poke_bp_batch+0x324/0x970 arch/x86/kernel/alternative.c:1419
 text_poke_flush arch/x86/kernel/alternative.c:1589 [inline]
 text_poke_finish+0x16/0x30 arch/x86/kernel/alternative.c:1596
 arch_jump_label_transform_apply+0x13/0x20 arch/x86/kernel/jump_label.c:146
 static_key_enable_cpuslocked+0x129/0x250 kernel/jump_label.c:177
 static_key_enable+0x16/0x20 kernel/jump_label.c:190
 toggle_allocation_gate+0xbf/0x470 mm/kfence/core.c:808
 process_one_work+0x81c/0xd10 kernel/workqueue.c:2289
 worker_thread+0xb14/0x1330 kernel/workqueue.c:2436
 kthread+0x266/0x300 kernel/kthread.c:376
 ret_from_fork+0x1f/0x30
 </TASK>
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 PID: 12379 Comm: syz-executor.3 Not tainted 5.19.0-rc1-syzkaller-00238-gaa3398fb4b3f #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
RIP: 0010:should_resched arch/x86/include/asm/preempt.h:103 [inline]
RIP: 0010:__raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:152 [inline]
RIP: 0010:_raw_spin_unlock_irqrestore+0xe0/0x130 kernel/locking/spinlock.c:194
Code: 4c 89 f7 e8 92 b9 a6 f7 f6 44 24 21 02 75 4e 41 f7 c7 00 02 00 00 74 01 fb bf 01 00 00 00 e8 27 3e 28 f7 65 8b 05 08 a8 ce 75 <85> c0 74 3f 48 c7 04 24 0e 36 e0 45 4b c7 04 2c 00 00 00 00 65 48
RSP: 0018:ffffc900001f0c80 EFLAGS: 00000013
RAX: 0000000000010002 RBX: 1ffff9200003e194 RCX: 0000000000010003
RDX: 0000000000000000 RSI: 0000000000000004 RDI: 0000000000000001
RBP: ffffc900001f0d10 R08: dffffc0000000000 R09: fffffbfff22ec983
R10: fffffbfff22ec983 R11: 1ffffffff22ec982 R12: dffffc0000000000
R13: 1ffff9200003e190 R14: ffffc900001f0ca0 R15: 0000000000000046
FS:  00007f4a01100700(0000) GS:ffff8880b9b00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f49fefbbfc0 CR3: 000000007a42f000 CR4: 00000000003506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <IRQ>
 debug_hrtimer_deactivate kernel/time/hrtimer.c:425 [inline]
 debug_deactivate kernel/time/hrtimer.c:481 [inline]
 __run_hrtimer kernel/time/hrtimer.c:1653 [inline]
 __hrtimer_run_queues+0x2f9/0xa60 kernel/time/hrtimer.c:1749
 hrtimer_interrupt+0x3a6/0xfd0 kernel/time/hrtimer.c:1811
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1095 [inline]
 __sysvec_apic_timer_interrupt+0xf9/0x280 arch/x86/kernel/apic/apic.c:1112
 sysvec_apic_timer_interrupt+0x8c/0xb0 arch/x86/kernel/apic/apic.c:1106
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x1b/0x20
RIP: 0010:finish_lock_switch+0x1c5/0x350 kernel/sched/core.c:4877
Code: be ff ff ff ff e8 bb af cc 08 85 c0 74 37 4d 85 e4 75 58 0f 1f 44 00 00 4c 89 ff e8 25 9b d5 08 e8 00 18 30 00 fb 48 83 c4 10 <5b> 41 5c 41 5d 41 5e 41 5f 5d c3 0f 0b 4d 85 e4 0f 85 4a ff ff ff
RSP: 0018:ffffc90006a1f528 EFLAGS: 00000286
RAX: b10c0746f9cc9800 RBX: 1ffff110173674c8 RCX: ffffffff9153de03
RDX: dffffc0000000000 RSI: ffffffff8a8d2140 RDI: ffffffff8ae98a20
RBP: ffff8880b9b3a640 R08: dffffc0000000000 R09: ffffed1017367371
R10: ffffed1017367371 R11: 1ffff11017367370 R12: 0000000000000000
R13: ffff8880b9b3a8d8 R14: dffffc0000000000 R15: ffff8880b9b39b80
 finish_task_switch+0x140/0x610 kernel/sched/core.c:4994
 context_switch kernel/sched/core.c:5119 [inline]
 __schedule+0x95f/0xec0 kernel/sched/core.c:6428
 schedule+0xeb/0x1b0 kernel/sched/core.c:6500
 schedule_hrtimeout_range_clock+0x277/0x470 kernel/time/hrtimer.c:2305
 poll_schedule_timeout+0x10b/0x150 fs/select.c:244
 do_poll fs/select.c:965 [inline]
 do_sys_poll+0x1060/0x1500 fs/select.c:1015
 __do_sys_poll fs/select.c:1080 [inline]
 __se_sys_poll+0x1ec/0x420 fs/select.c:1068
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x2b/0x70 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x46/0xb0
RIP: 0033:0x7f4a00089109
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 b8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f4a01100168 EFLAGS: 00000246 ORIG_RAX: 0000000000000007
RAX: ffffffffffffffda RBX: 00007f4a0019bf60 RCX: 00007f4a00089109
RDX: 00000000000001ff RSI: 0000000000000001 RDI: 0000000020000200
RBP: 00007f4a000e30ad R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007ffdd12ab1ff R14: 00007f4a01100300 R15: 0000000000022000
 </TASK>
----------------
Code disassembly (best guess), 1 bytes skipped:
   0:	0f 83 ac 00 00 00    	jae    0xb2
   6:	89 d8                	mov    %ebx,%eax
   8:	c1 e8 06             	shr    $0x6,%eax
   b:	48 8d 3c c5 68 82 03 	lea    -0x71fc7d98(,%rax,8),%rdi
  12:	8e
  13:	be 08 00 00 00       	mov    $0x8,%esi
  18:	e8 e9 bd 72 00       	callq  0x72be06
  1d:	89 d8                	mov    %ebx,%eax
  1f:	48 0f a3 05 37 be 9b 	bt     %rax,0xc9bbe37(%rip)        # 0xc9bbe5e
  26:	0c
  27:	73 47                	jae    0x70
* 29:	65 ff 05 ce aa 9a 7e 	incl   %gs:0x7e9aaace(%rip)        # 0x7e9aaafe <-- trapping instruction
  30:	48 c7 c0 58 35 f0 8d 	mov    $0xffffffff8df03558,%rax
  37:	48 c1 e8 03          	shr    $0x3,%rax
  3b:	48                   	rex.W
  3c:	b9                   	.byte 0xb9

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2022/06/11 03:15 upstream aa3398fb4b3f 0d5abf15 .config console log report info ci-upstream-kasan-gce-smack-root INFO: rcu detected stall in sys_poll
* Struck through repros no longer work on HEAD.