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INFO: rcu detected stall in __mod_timer (4)

Status: auto-obsoleted due to no activity on 2022/12/03 01:18
Subsystems: net
[Documentation on labels]
First crash: 599d, last: 599d
Similar bugs (3)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream INFO: rcu detected stall in __mod_timer (3) perf 24 815d 1041d 0/26 closed as invalid on 2022/02/08 10:00
upstream INFO: rcu detected stall in __mod_timer kernel 1 1502d 1502d 0/26 auto-closed as invalid on 2020/06/13 13:03
upstream INFO: rcu detected stall in __mod_timer (2) kernel 17 1185d 1392d 0/26 auto-closed as invalid on 2021/05/17 11:36

Sample crash report:
rcu: INFO: rcu_preempt self-detected stall on CPU
rcu: 	0-....: (1 GPs behind) idle=66dc/1/0x4000000000000000 softirq=116804/116805 fqs=1130
	(t=10501 jiffies g=187081 q=320 ncpus=2)
NMI backtrace for cpu 0
CPU: 0 PID: 30047 Comm: kworker/0:0 Not tainted 6.0.0-rc3-syzkaller-00557-gaa3fab011058 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/26/2022
Workqueue: events nsim_dev_trap_report_work
Call Trace:
 <IRQ>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0xcd/0x134 lib/dump_stack.c:106
 nmi_cpu_backtrace.cold+0x46/0x14f lib/nmi_backtrace.c:111
 nmi_trigger_cpumask_backtrace+0x206/0x250 lib/nmi_backtrace.c:62
 trigger_single_cpu_backtrace include/linux/nmi.h:166 [inline]
 rcu_dump_cpu_stacks+0x2c7/0x4d0 kernel/rcu/tree_stall.h:371
 print_cpu_stall kernel/rcu/tree_stall.h:660 [inline]
 check_cpu_stall kernel/rcu/tree_stall.h:744 [inline]
 rcu_pending kernel/rcu/tree.c:3660 [inline]
 rcu_sched_clock_irq.cold+0x9f/0x79c kernel/rcu/tree.c:2342
 update_process_times+0x11a/0x1a0 kernel/time/timer.c:1839
 tick_sched_handle+0x9b/0x180 kernel/time/tick-sched.c:243
 tick_sched_timer+0xee/0x120 kernel/time/tick-sched.c:1480
 __run_hrtimer kernel/time/hrtimer.c:1685 [inline]
 __hrtimer_run_queues+0x1c0/0xe40 kernel/time/hrtimer.c:1749
 hrtimer_interrupt+0x31c/0x790 kernel/time/hrtimer.c:1811
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1095 [inline]
 __sysvec_apic_timer_interrupt+0x146/0x530 arch/x86/kernel/apic/apic.c:1112
 sysvec_apic_timer_interrupt+0x40/0xc0 arch/x86/kernel/apic/apic.c:1106
 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:649
RIP: 0010:__raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:152 [inline]
RIP: 0010:_raw_spin_unlock_irqrestore+0x38/0x70 kernel/locking/spinlock.c:194
Code: 74 24 10 e8 5a 18 dc f7 48 89 ef e8 e2 99 dc f7 81 e3 00 02 00 00 75 25 9c 58 f6 c4 02 75 2d 48 85 db 74 01 fb bf 01 00 00 00 <e8> 93 5b cf f7 65 8b 05 4c 11 7f 76 85 c0 74 0a 5b 5d c3 e8 10 21
RSP: 0018:ffffc90000007c28 EFLAGS: 00000206
RAX: 0000000000000006 RBX: 0000000000000200 RCX: 1ffffffff2127a1e
RDX: 0000000000000000 RSI: 0000000000000103 RDI: 0000000000000001
RBP: ffff8880b9a283c0 R08: 0000000000000001 R09: ffffffff908e3a2f
R10: 0000000000000001 R11: 0000000000000001 R12: 0000000100038e7e
R13: ffff8880b9a283c0 R14: 0000000000000000 R15: 00000000ffffffff
 __mod_timer+0x837/0xe30 kernel/time/timer.c:1118
 call_timer_fn+0x1a0/0x6b0 kernel/time/timer.c:1474
 expire_timers kernel/time/timer.c:1519 [inline]
 __run_timers.part.0+0x674/0xa80 kernel/time/timer.c:1790
 __run_timers kernel/time/timer.c:1768 [inline]
 run_timer_softirq+0xb3/0x1d0 kernel/time/timer.c:1803
 __do_softirq+0x1d3/0x9c6 kernel/softirq.c:571
 do_softirq.part.0+0xde/0x130 kernel/softirq.c:472
 </IRQ>
 <TASK>
 do_softirq kernel/softirq.c:464 [inline]
 __local_bh_enable_ip+0x102/0x120 kernel/softirq.c:396
 spin_unlock_bh include/linux/spinlock.h:394 [inline]
 nsim_dev_trap_report drivers/net/netdevsim/dev.c:814 [inline]
 nsim_dev_trap_report_work+0x869/0xc50 drivers/net/netdevsim/dev.c:844
 process_one_work+0x991/0x1610 kernel/workqueue.c:2289
 worker_thread+0x665/0x1080 kernel/workqueue.c:2436
 kthread+0x2e4/0x3a0 kernel/kthread.c:376
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:306
 </TASK>

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2022/09/04 01:12 net-next-old aa3fab011058 28811d0a .config console log report info ci-upstream-net-kasan-gce INFO: rcu detected stall in __mod_timer
* Struck through repros no longer work on HEAD.