syzbot


INFO: rcu detected stall in sys_ppoll

Status: upstream: reported on 2024/07/30 19:19
Reported-by: syzbot+e17b6eebfac95009e5a8@syzkaller.appspotmail.com
First crash: 84d, last: 84d

Sample crash report:
rcu: INFO: rcu_preempt self-detected stall on CPU
rcu: 	1-...!: (1 GPs behind) idle=c37/1/0x4000000000000000 softirq=42579/42590 fqs=0 
	(t=11787 jiffies g=52317 q=1127)
rcu: rcu_preempt kthread timer wakeup didn't happen for 11786 jiffies! g52317 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402
rcu: 	Possible timer handling issue on cpu=0 timer-softirq=23486
rcu: rcu_preempt kthread starved for 11787 jiffies! g52317 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402 ->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:I stack:27064 pid:   15 ppid:     2 flags:0x00004000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5030 [inline]
 __schedule+0x12c4/0x45b0 kernel/sched/core.c:6376
 schedule+0x11b/0x1f0 kernel/sched/core.c:6459
 schedule_timeout+0x1b9/0x300 kernel/time/timer.c:1914
 rcu_gp_fqs_loop+0x2bf/0x1080 kernel/rcu/tree.c:1972
 rcu_gp_kthread+0xa4/0x360 kernel/rcu/tree.c:2145
 kthread+0x3f6/0x4f0 kernel/kthread.c:334
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287
 </TASK>
rcu: Stack dump where RCU GP kthread last ran:
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 PID: 3383 Comm: dhcpcd Not tainted 5.15.164-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/27/2024
RIP: 0010:__raw_callee_save___pv_queued_spin_unlock+0xc/0x12
Code: 56 57 41 50 41 51 41 52 41 53 e8 bf 0a 00 00 41 5b 41 5a 41 59 41 58 5f 5e 5a 59 c3 66 90 52 b8 01 00 00 00 31 d2 f0 0f b0 17 <3c> 01 75 02 5a c3 56 0f b6 f0 e8 c5 ff ff ff 5e 5a c3 66 90 55 48
RSP: 0018:ffffc90000007c30 EFLAGS: 00000046
RAX: 0000000000000001 RBX: 1ffffffff22cb48b RCX: 0000000000000000
RDX: 0000000000000000 RSI: 0000000000000004 RDI: ffffffff9165a450
RBP: dffffc0000000000 R08: dffffc0000000000 R09: fffffbfff22cb48b
R10: 0000000000000000 R11: dffffc0000000001 R12: 1ffffffff22cb48c
R13: ffffffff9165a460 R14: ffffffff9165a458 R15: ffffffff9165a450
FS:  00007f8d6c9b5740(0000) GS:ffff8880b9a00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007ffc0a458e6c CR3: 000000001adaa000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <NMI>
 </NMI>
 <IRQ>
 pv_queued_spin_unlock arch/x86/include/asm/paravirt.h:590 [inline]
 queued_spin_unlock arch/x86/include/asm/qspinlock.h:56 [inline]
 do_raw_spin_unlock+0x137/0x8b0 kernel/locking/spinlock_debug.c:141
 __raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:159 [inline]
 _raw_spin_unlock_irqrestore+0x7d/0x130 kernel/locking/spinlock.c:194
 debug_hrtimer_deactivate kernel/time/hrtimer.c:425 [inline]
 debug_deactivate+0x1b/0x1e0 kernel/time/hrtimer.c:481
 __run_hrtimer kernel/time/hrtimer.c:1654 [inline]
 __hrtimer_run_queues+0x31d/0xcf0 kernel/time/hrtimer.c:1750
 hrtimer_interrupt+0x392/0x980 kernel/time/hrtimer.c:1812
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1085 [inline]
 __sysvec_apic_timer_interrupt+0x139/0x470 arch/x86/kernel/apic/apic.c:1102
 sysvec_apic_timer_interrupt+0x8c/0xb0 arch/x86/kernel/apic/apic.c:1096
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:638
RIP: 0010:finish_lock_switch+0x91/0x100 kernel/sched/core.c:4785
Code: 45 31 c9 68 c7 99 59 81 e8 5c 12 09 00 48 83 c4 08 4c 89 ff e8 60 da fe ff 66 90 4c 89 ff e8 56 09 e3 08 e8 d1 47 2d 00 fb 5b <41> 5c 41 5d 41 5e 41 5f c3 44 89 f1 80 e1 07 80 c1 03 38 c1 7c 87
RSP: 0018:ffffc90002187438 EFLAGS: 00000286
RAX: 5c2525620018fc00 RBX: ffff88801dd23bb4 RCX: ffffffff91467f03
RDX: dffffc0000000000 RSI: ffffffff8a8b2a00 RDI: ffffffff8ad8f800
RBP: ffffc900021874b0 R08: ffffffff8186e200 R09: ffffed1017347469
R10: 0000000000000000 R11: dffffc0000000001 R12: dffffc0000000000
R13: 1ffff11017347613 R14: ffff8880b9a3b098 R15: ffff8880b9a3a340
 finish_task_switch+0x134/0x630 kernel/sched/core.c:4902
 context_switch kernel/sched/core.c:5033 [inline]
 __schedule+0x12cc/0x45b0 kernel/sched/core.c:6376
 schedule+0x11b/0x1f0 kernel/sched/core.c:6459
 schedule_hrtimeout_range_clock+0x2e3/0x4a0 kernel/time/hrtimer.c:2292
 poll_schedule_timeout+0x10c/0x150 fs/select.c:243
 do_poll fs/select.c:964 [inline]
 do_sys_poll+0xd61/0x11f0 fs/select.c:1014
 __do_sys_ppoll fs/select.c:1120 [inline]
 __se_sys_ppoll+0x29c/0x330 fs/select.c:1100
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7f8d6ca82ad5
Code: 85 d2 74 0d 0f 10 02 48 8d 54 24 20 0f 11 44 24 20 64 8b 04 25 18 00 00 00 85 c0 75 27 41 b8 08 00 00 00 b8 0f 01 00 00 0f 05 <48> 3d 00 f0 ff ff 76 75 48 8b 15 24 73 0d 00 f7 d8 64 89 02 48 83
RSP: 002b:00007ffc0a459770 EFLAGS: 00000246 ORIG_RAX: 000000000000010f
RAX: ffffffffffffffda RBX: 0000558608abee20 RCX: 00007f8d6ca82ad5
RDX: 0000000000000000 RSI: 0000000000000002 RDI: 0000558608ac9a80
RBP: 00007ffc0a459ac0 R08: 0000000000000008 R09: 0000000000000000
R10: 00007ffc0a459ac0 R11: 0000000000000246 R12: 0000000000000000
R13: 000055860880e610 R14: 0000000000000000 R15: 0000000000000000
 </TASK>
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 PID: 3383 Comm: dhcpcd Not tainted 5.15.164-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/27/2024
RIP: 0010:__sanitizer_cov_trace_pc+0x0/0x60 kernel/kcov.c:193
Code: 1f 84 00 00 00 00 00 0f 1f 00 53 48 89 fb e8 17 00 00 00 48 8b 3d 08 ed 68 0c 48 89 de 5b e9 c7 fc 48 00 cc cc cc cc cc cc cc <48> 8b 04 24 65 48 8b 0d 54 0e 82 7e 65 8b 15 55 0e 82 7e f7 c2 00
RSP: 0018:ffffc90000007cb8 EFLAGS: 00000086
RAX: 0000000000000000 RBX: dffffc0000000000 RCX: 0000000000000002
RDX: 0000000000010002 RSI: ffff888023ae4b40 RDI: ffff8880b9a2a3d0
RBP: ffff8880b9a2a244 R08: ffffffff816f955e R09: fffffbfff1bd2986
R10: 0000000000000000 R11: dffffc0000000001 R12: ffff8880b9a2a3d0
R13: ffff8880b9a2a3d0 R14: ffff888023ae4b40 R15: ffff888023ae4b40
FS:  00007f8d6c9b5740(0000) GS:ffff8880b9a00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007ffc0a458e6c CR3: 000000001adaa000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <NMI>
 </NMI>
 <IRQ>
 timerqueue_add+0x23/0x280 lib/timerqueue.c:36
 enqueue_hrtimer+0x1a0/0x390 kernel/time/hrtimer.c:1092
 __run_hrtimer kernel/time/hrtimer.c:1703 [inline]
 __hrtimer_run_queues+0x6b6/0xcf0 kernel/time/hrtimer.c:1750
 hrtimer_interrupt+0x392/0x980 kernel/time/hrtimer.c:1812
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1085 [inline]
 __sysvec_apic_timer_interrupt+0x139/0x470 arch/x86/kernel/apic/apic.c:1102
 sysvec_apic_timer_interrupt+0x8c/0xb0 arch/x86/kernel/apic/apic.c:1096
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:638
RIP: 0010:finish_lock_switch+0x91/0x100 kernel/sched/core.c:4785
Code: 45 31 c9 68 c7 99 59 81 e8 5c 12 09 00 48 83 c4 08 4c 89 ff e8 60 da fe ff 66 90 4c 89 ff e8 56 09 e3 08 e8 d1 47 2d 00 fb 5b <41> 5c 41 5d 41 5e 41 5f c3 44 89 f1 80 e1 07 80 c1 03 38 c1 7c 87
RSP: 0018:ffffc90002187438 EFLAGS: 00000286
RAX: 5c2525620018fc00 RBX: ffff88801dd23bb4 RCX: ffffffff91467f03
RDX: dffffc0000000000 RSI: ffffffff8a8b2a00 RDI: ffffffff8ad8f800
RBP: ffffc900021874b0 R08: ffffffff8186e200 R09: ffffed1017347469
R10: 0000000000000000 R11: dffffc0000000001 R12: dffffc0000000000
R13: 1ffff11017347613 R14: ffff8880b9a3b098 R15: ffff8880b9a3a340
 finish_task_switch+0x134/0x630 kernel/sched/core.c:4902
 context_switch kernel/sched/core.c:5033 [inline]
 __schedule+0x12cc/0x45b0 kernel/sched/core.c:6376
 schedule+0x11b/0x1f0 kernel/sched/core.c:6459
 schedule_hrtimeout_range_clock+0x2e3/0x4a0 kernel/time/hrtimer.c:2292
 poll_schedule_timeout+0x10c/0x150 fs/select.c:243
 do_poll fs/select.c:964 [inline]
 do_sys_poll+0xd61/0x11f0 fs/select.c:1014
 __do_sys_ppoll fs/select.c:1120 [inline]
 __se_sys_ppoll+0x29c/0x330 fs/select.c:1100
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7f8d6ca82ad5
Code: 85 d2 74 0d 0f 10 02 48 8d 54 24 20 0f 11 44 24 20 64 8b 04 25 18 00 00 00 85 c0 75 27 41 b8 08 00 00 00 b8 0f 01 00 00 0f 05 <48> 3d 00 f0 ff ff 76 75 48 8b 15 24 73 0d 00 f7 d8 64 89 02 48 83
RSP: 002b:00007ffc0a459770 EFLAGS: 00000246 ORIG_RAX: 000000000000010f
RAX: ffffffffffffffda RBX: 0000558608abee20 RCX: 00007f8d6ca82ad5
RDX: 0000000000000000 RSI: 0000000000000002 RDI: 0000558608ac9a80
RBP: 00007ffc0a459ac0 R08: 0000000000000008 R09: 0000000000000000
R10: 00007ffc0a459ac0 R11: 0000000000000246 R12: 0000000000000000
R13: 000055860880e610 R14: 0000000000000000 R15: 0000000000000000
 </TASK>
NMI backtrace for cpu 1
CPU: 1 PID: 1075 Comm: kworker/1:2 Not tainted 5.15.164-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/27/2024
Workqueue: events_power_efficient gc_worker
Call Trace:
 <IRQ>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0x1e3/0x2d0 lib/dump_stack.c:106
 nmi_cpu_backtrace+0x46a/0x4a0 lib/nmi_backtrace.c:111
 nmi_trigger_cpumask_backtrace+0x181/0x2a0 lib/nmi_backtrace.c:62
 trigger_single_cpu_backtrace include/linux/nmi.h:166 [inline]
 rcu_dump_cpu_stacks+0x223/0x390 kernel/rcu/tree_stall.h:349
 print_cpu_stall+0x320/0x600 kernel/rcu/tree_stall.h:633
 check_cpu_stall kernel/rcu/tree_stall.h:727 [inline]
 rcu_pending kernel/rcu/tree.c:3932 [inline]
 rcu_sched_clock_irq+0x8d9/0x1150 kernel/rcu/tree.c:2619
 update_process_times+0x196/0x200 kernel/time/timer.c:1818
 tick_sched_handle kernel/time/tick-sched.c:254 [inline]
 tick_sched_timer+0x386/0x550 kernel/time/tick-sched.c:1473
 __run_hrtimer kernel/time/hrtimer.c:1686 [inline]
 __hrtimer_run_queues+0x55b/0xcf0 kernel/time/hrtimer.c:1750
 hrtimer_interrupt+0x392/0x980 kernel/time/hrtimer.c:1812
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1085 [inline]
 __sysvec_apic_timer_interrupt+0x139/0x470 arch/x86/kernel/apic/apic.c:1102
 sysvec_apic_timer_interrupt+0x8c/0xb0 arch/x86/kernel/apic/apic.c:1096
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:638
RIP: 0010:seqcount_lockdep_reader_access+0x1dc/0x220 include/linux/seqlock.h:106
Code: f8 4d 85 ed 75 16 e8 b3 c0 f0 f8 eb 15 e8 ac c0 f0 f8 e8 b7 6c a3 01 4d 85 ed 74 ea e8 9d c0 f0 f8 fb 48 c7 04 24 0e 36 e0 45 <4b> c7 04 3c 00 00 00 00 66 43 c7 44 3c 09 00 00 43 c6 44 3c 0b 00
RSP: 0018:ffffc90004bd7a40 EFLAGS: 00000293
RAX: ffffffff888fa0c3 RBX: 0000000000000000 RCX: ffff88801befbb80
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: ffffc90004bd7af0 R08: ffffffff888fa099 R09: fffffbfff1f8e02b
R10: 0000000000000000 R11: dffffc0000000001 R12: dffffc0000000000
R13: 0000000000000200 R14: 0000000000000046 R15: 1ffff9200097af48
 nf_conntrack_get_ht include/net/netfilter/nf_conntrack.h:338 [inline]
 gc_worker+0x30f/0x14b0 net/netfilter/nf_conntrack_core.c:1472
 process_one_work+0x8a1/0x10c0 kernel/workqueue.c:2310
 worker_thread+0xaca/0x1280 kernel/workqueue.c:2457
 kthread+0x3f6/0x4f0 kernel/kthread.c:334
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287
 </TASK>

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2024/07/30 19:18 linux-5.15.y 7e89efd3ae1c 6fde257d .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in sys_ppoll
* Struck through repros no longer work on HEAD.