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INFO: rcu detected stall in sys_timerfd_settime

Status: auto-obsoleted due to no activity on 2023/09/22 02:06
Reported-by: syzbot+42cab3ff8100a09b7d3e@syzkaller.appspotmail.com
First crash: 339d, last: 339d
▶ ▼ Similar bugs (4)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream INFO: rcu detected stall in sys_timerfd_settime fs 3 918d 985d 0/26 closed as invalid on 2022/02/08 09:50
upstream INFO: rcu detected stall in sys_timerfd_settime (2) net 1 487d 487d 0/26 auto-obsoleted due to no activity on 2023/04/25 06:19
upstream INFO: rcu detected stall in sys_timerfd_settime (3) fs 2 129d 182d 0/26 auto-obsoleted due to no activity on 2024/04/09 00:01
linux-6.1 INFO: rcu detected stall in sys_timerfd_settime 1 331d 331d 0/3 auto-obsoleted due to no activity on 2023/09/29 23:03

Sample crash report:
rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	0-...!: (1 GPs behind) idle=947/1/0x4000000000000000 softirq=133666/133670 fqs=418 
	(detected by 1, t=10502 jiffies, g=214085, q=180)
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 PID: 31798 Comm: syz-executor.2 Not tainted 5.15.116-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/25/2023
RIP: 0010:validate_chain+0x1/0x58b0 kernel/locking/lockdep.c:3743
Code: e3 8d 80 e1 07 80 c1 03 38 c1 7c 92 48 c7 c7 08 f7 e3 8d e8 b1 2e 66 00 eb 84 e8 ca c2 b7 08 66 2e 0f 1f 84 00 00 00 00 00 55 <48> 89 e5 41 57 41 56 41 55 41 54 53 48 83 e4 e0 48 81 ec 80 02 00
RSP: 0018:ffffc90000007a50 EFLAGS: 00000086
RAX: 1ffffffff1f31c90 RBX: ffffffff8f98e480 RCX: eaf279c302216aba
RDX: 0000000000000001 RSI: ffff88807b1ee430 RDI: ffff88807b1ed940
RBP: eaf279c302216aba R08: dffffc0000000000 R09: fffffbfff1f79665
R10: 0000000000000000 R11: dffffc0000000001 R12: 0000000000000000
R13: ffff88807b1ee428 R14: ffff88807b1ed940 R15: ffff88807b1ee450
FS:  00007f02b9ec1700(0000) GS:ffff8880b9a00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000020000280 CR3: 000000002ed99000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <NMI>
 </NMI>
 <IRQ>
 __lock_acquire+0x1295/0x1ff0 kernel/locking/lockdep.c:5011
 lock_acquire+0x1db/0x4f0 kernel/locking/lockdep.c:5622
 __raw_spin_lock include/linux/spinlock_api_smp.h:142 [inline]
 _raw_spin_lock+0x2a/0x40 kernel/locking/spinlock.c:154
 spin_lock include/linux/spinlock.h:363 [inline]
 advance_sched+0x47/0x940 net/sched/sch_taprio.c:716
 __run_hrtimer kernel/time/hrtimer.c:1685 [inline]
 __hrtimer_run_queues+0x598/0xcf0 kernel/time/hrtimer.c:1749
 hrtimer_interrupt+0x392/0x980 kernel/time/hrtimer.c:1811
 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:__raw_spin_unlock_irq include/linux/spinlock_api_smp.h:169 [inline]
RIP: 0010:_raw_spin_unlock_irq+0x25/0x40 kernel/locking/spinlock.c:202
Code: 31 9f f6 ff 90 53 48 89 fb 48 83 c7 18 48 8b 74 24 08 e8 2e 4a 3e f7 48 89 df e8 c6 9c 3f f7 e8 c1 20 62 f7 fb bf 01 00 00 00 <e8> 46 da 32 f7 65 8b 05 47 26 de 75 85 c0 74 02 5b c3 e8 54 3d dc
RSP: 0018:ffffc90003d7fd20 EFLAGS: 00000282
RAX: 8a0f705152339b00 RBX: ffff88801db38c88 RCX: ffffffff913c3003
RDX: dffffc0000000000 RSI: ffffffff8a8afc60 RDI: 0000000000000001
RBP: 00000000ffffff83 R08: ffffffff81866a60 R09: ffffed1003b67192
R10: 0000000000000000 R11: dffffc0000000001 R12: ffff88801db38c00
R13: 7fffffffffffffff R14: ffff88801db38c80 R15: 0000000000000003
 spin_unlock_irq include/linux/spinlock.h:413 [inline]
 do_timerfd_settime+0xd1a/0x1000 fs/timerfd.c:521
 __do_sys_timerfd_settime fs/timerfd.c:567 [inline]
 __se_sys_timerfd_settime fs/timerfd.c:558 [inline]
 __x64_sys_timerfd_settime+0x16b/0x220 fs/timerfd.c:558
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x3d/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x61/0xcb
RIP: 0033:0x7f02bb94f199
Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 f1 19 00 00 90 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:00007f02b9ec1168 EFLAGS: 00000246 ORIG_RAX: 000000000000011e
RAX: ffffffffffffffda RBX: 00007f02bba6ef80 RCX: 00007f02bb94f199
RDX: 0000000020000100 RSI: 0000000000000003 RDI: 0000000000000003
RBP: 00007f02bb9aaca1 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007ffd14c4c32f R14: 00007f02b9ec1300 R15: 0000000000022000
 </TASK>
rcu: rcu_preempt kthread starved for 9666 jiffies! g214085 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:26616 pid:   15 ppid:     2 flags:0x00004000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5026 [inline]
 __schedule+0x12c4/0x4590 kernel/sched/core.c:6372
 schedule+0x11b/0x1f0 kernel/sched/core.c:6455
 schedule_timeout+0x1b9/0x300 kernel/time/timer.c:1884
 rcu_gp_fqs_loop+0x2af/0xf70 kernel/rcu/tree.c:1959
 rcu_gp_kthread+0xa4/0x360 kernel/rcu/tree.c:2132
 kthread+0x3f6/0x4f0 kernel/kthread.c:319
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:298
 </TASK>
rcu: Stack dump where RCU GP kthread last ran:
NMI backtrace for cpu 1
CPU: 1 PID: 3740 Comm: kworker/1:10 Not tainted 5.15.116-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/25/2023
Workqueue: events bpf_map_free_deferred
Call Trace:
 <IRQ>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0x1e3/0x2cb 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_check_gp_kthread_starvation+0x1d2/0x240 kernel/rcu/tree_stall.h:481
 print_other_cpu_stall+0x137a/0x14d0 kernel/rcu/tree_stall.h:586
 check_cpu_stall kernel/rcu/tree_stall.h:729 [inline]
 rcu_pending kernel/rcu/tree.c:3888 [inline]
 rcu_sched_clock_irq+0x94f/0x1770 kernel/rcu/tree.c:2606
 update_process_times+0x196/0x200 kernel/time/timer.c:1788
 tick_sched_handle kernel/time/tick-sched.c:226 [inline]
 tick_sched_timer+0x22d/0x3c0 kernel/time/tick-sched.c:1430
 __run_hrtimer kernel/time/hrtimer.c:1685 [inline]
 __hrtimer_run_queues+0x55b/0xcf0 kernel/time/hrtimer.c:1749
 hrtimer_interrupt+0x392/0x980 kernel/time/hrtimer.c:1811
 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:__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 58 cc 63 0c 48 89 de 5b e9 07 84 48 00 cc cc cc cc cc cc cc <48> 8b 04 24 65 48 8b 0d 64 76 82 7e 65 8b 15 65 76 82 7e f7 c2 00
RSP: 0018:ffffc9000486f9f8 EFLAGS: 00000202
RAX: 0000000000000000 RBX: 1ffff9200090df49 RCX: ffff88807925d940
RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000000
RBP: ffffc9000486faf0 R08: ffffffff81743460 R09: ffffed10173474e9
R10: 0000000000000000 R11: dffffc0000000001 R12: dffffc0000000000
R13: 0000000000000001 R14: ffffc9000486fa48 R15: 0000000000000000
 csd_lock_wait kernel/smp.c:440 [inline]
 smp_call_function_single+0x2ae/0x530 kernel/smp.c:758
 rcu_barrier+0x262/0x4e0 kernel/rcu/tree.c:4034
 htab_map_free+0x25/0x5e0 kernel/bpf/hashtab.c:1466
 process_one_work+0x8a1/0x10c0 kernel/workqueue.c:2307
 worker_thread+0xaca/0x1280 kernel/workqueue.c:2454
 kthread+0x3f6/0x4f0 kernel/kthread.c:319
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:298
 </TASK>

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2023/06/14 02:06 linux-5.15.y 7349e40704a0 d2ee9228 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in sys_timerfd_settime
* Struck through repros no longer work on HEAD.