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INFO: rcu detected stall in sync_hw_clock (2)

Status: auto-obsoleted due to no activity on 2025/02/13 00:09
Subsystems: rtc
[Documentation on labels]
First crash: 236d, last: 224d
▶ ▼ Similar bugs (4)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
linux-5.15 INFO: rcu detected stall in sync_hw_clock origin:upstream C 2 7d06h 540d 0/3 upstream: reported C repro on 2024/01/04 12:38
upstream INFO: rcu detected stall in sync_hw_clock kernel 3 895d 944d 0/29 auto-obsoleted due to no activity on 2023/04/21 23:58
linux-6.1 INFO: rcu detected stall in sync_hw_clock 2 165d 168d 0/3 auto-obsoleted due to no activity on 2025/04/23 12:58
upstream BUG: soft lockup in sync_hw_clock efi C 1 436d 432d 0/29 auto-obsoleted due to no activity on 2024/07/26 14:56

Sample crash report:
rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	0-...!: (0 ticks this GP) idle=a594/1/0x4000000000000000 softirq=54998/54998 fqs=0
rcu: 	(detected by 1, t=10506 jiffies, g=44029, q=214 ncpus=2)
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 8 Comm: kworker/0:0 Not tainted 6.12.0-rc7-syzkaller-00070-g0a9b9d17f3a7 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/30/2024
Workqueue: events_freezable_pwr_efficient sync_hw_clock
RIP: 0010:rcu_is_watching_curr_cpu include/linux/context_tracking.h:128 [inline]
RIP: 0010:rcu_is_watching+0x41/0xc0 kernel/rcu/tree.c:737
Code: 03 00 83 f8 07 89 c5 0f 87 82 00 00 00 48 8d 3c ed 80 4b a6 8d 48 b8 00 00 00 00 00 fc ff df 48 89 fa 48 c1 ea 03 80 3c 02 00 <75> 5c 48 03 1c ed 80 4b a6 8d 48 b8 00 00 00 00 00 fc ff df 48 89
RSP: 0018:ffffc90000007c90 EFLAGS: 00000046
RAX: dffffc0000000000 RBX: 0000000000038128 RCX: ffffffff816a9d09
RDX: 1ffffffff1b4c970 RSI: ffffffff8bd1b440 RDI: ffffffff8da64b80
RBP: 0000000000000000 R08: 0000000000000000 R09: fffffbfff20beb71
R10: ffffffff905f5b8f R11: 0000000000000000 R12: ffff88805e837300
R13: ffff888035b9a000 R14: 000000000003dc0c R15: ffff88807f608400
FS:  0000000000000000(0000) GS:ffff8880b8600000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000000000000 CR3: 000000007e4a6000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <NMI>
 </NMI>
 <IRQ>
 trace_lock_release include/trace/events/lock.h:69 [inline]
 lock_release+0x4f6/0x6f0 kernel/locking/lockdep.c:5836
 __raw_spin_unlock include/linux/spinlock_api_smp.h:141 [inline]
 _raw_spin_unlock+0x16/0x50 kernel/locking/spinlock.c:186
 spin_unlock include/linux/spinlock.h:391 [inline]
 advance_sched+0x611/0xc60 net/sched/sch_taprio.c:981
 __run_hrtimer kernel/time/hrtimer.c:1691 [inline]
 __hrtimer_run_queues+0x20a/0xae0 kernel/time/hrtimer.c:1755
 hrtimer_interrupt+0x31b/0x800 kernel/time/hrtimer.c:1817
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1038 [inline]
 __sysvec_apic_timer_interrupt+0x10f/0x400 arch/x86/kernel/apic/apic.c:1055
 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1049 [inline]
 sysvec_apic_timer_interrupt+0x9f/0xc0 arch/x86/kernel/apic/apic.c:1049
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702
RIP: 0010:__raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:152 [inline]
RIP: 0010:_raw_spin_unlock_irqrestore+0x31/0x80 kernel/locking/spinlock.c:194
Code: f5 53 48 8b 74 24 10 48 89 fb 48 83 c7 18 e8 b6 82 44 f6 48 89 df e8 ce ff 44 f6 f7 c5 00 02 00 00 75 23 9c 58 f6 c4 02 75 37 <bf> 01 00 00 00 e8 e5 08 36 f6 65 8b 05 36 c2 dd 74 85 c0 74 16 5b
RSP: 0018:ffffc900000d7b00 EFLAGS: 00000246
RAX: 0000000000000006 RBX: ffff8880b862c9c0 RCX: 1ffffffff2ddcc80
RDX: 0000000000000000 RSI: ffffffff8b6ccfc0 RDI: ffffffff8bd1b4c0
RBP: 0000000000000246 R08: 0000000000000001 R09: fffffbfff2dc5dc2
R10: ffffffff96e2ee17 R11: ffffffff8b6f86c0 R12: 0000000000000000
R13: ffffffff9a82d2e0 R14: 0000000000000080 R15: ffff8880b862cac0
 unlock_hrtimer_base kernel/time/hrtimer.c:1016 [inline]
 hrtimer_start_range_ns+0x4a7/0xc60 kernel/time/hrtimer.c:1305
 hrtimer_start include/linux/hrtimer.h:275 [inline]
 sched_sync_hw_clock kernel/time/ntp.c:519 [inline]
 sync_hw_clock+0x34e/0x520 kernel/time/ntp.c:660
 process_one_work+0x9c5/0x1ba0 kernel/workqueue.c:3229
 process_scheduled_works kernel/workqueue.c:3310 [inline]
 worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
 kthread+0x2c1/0x3a0 kernel/kthread.c:389
 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
 </TASK>
rcu: rcu_preempt kthread timer wakeup didn't happen for 10505 jiffies! g44029 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402
rcu: 	Possible timer handling issue on cpu=0 timer-softirq=35233
rcu: rcu_preempt kthread starved for 10506 jiffies! g44029 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:27504 pid:17    tgid:17    ppid:2      flags:0x00004000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5328 [inline]
 __schedule+0xe55/0x5740 kernel/sched/core.c:6693
 __schedule_loop kernel/sched/core.c:6770 [inline]
 schedule+0xe7/0x350 kernel/sched/core.c:6785
 schedule_timeout+0x136/0x2a0 kernel/time/timer.c:2615
 rcu_gp_fqs_loop+0x1eb/0xb00 kernel/rcu/tree.c:2045
 rcu_gp_kthread+0x271/0x380 kernel/rcu/tree.c:2247
 kthread+0x2c1/0x3a0 kernel/kthread.c:389
 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
 </TASK>

Crashes (2):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2024/11/15 00:08 upstream 0a9b9d17f3a7 77f3eeb7 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-selinux-root INFO: rcu detected stall in sync_hw_clock
2024/11/03 19:42 upstream b9021de3ec2f f00eed24 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-selinux-root INFO: rcu detected stall in sync_hw_clock
* Struck through repros no longer work on HEAD.