INFO: rcu detected stall in process_one_work

[syzbot]

Hello,

syzbot found the following crash on:

HEAD commit: bc2dbc5420e8 Merge branch 'akpm' (patches from Andrew)
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=127294d7800000
kernel config: https://syzkaller.appspot.com/x/.config?x=982e2df1b9e60b02
dashboard link: https://syzkaller.appspot.com/bug?extid=0efa75891ba0cdaa377b
compiler: gcc (GCC) 8.0.1 20180413 (experimental)
CC: [a.z...@towertech.it alexandr...@bootlin.com
linux-...@vger.kernel.org linu...@vger.kernel.org]

Unfortunately, I don't have any reproducer for this crash yet.

IMPORTANT: if you fix the bug, please add the following tag to the commit:
Reported-by: syzbot+0efa75...@syzkaller.appspotmail.com

INFO: rcu_sched self-detected stall on CPU
0-....: (124999 ticks this GP) idle=b76/1/4611686018427387906
softirq=62963/62963 fqs=31239
(t=125000 jiffies g=32248 c=32247 q=1124)
NMI backtrace for cpu 0
CPU: 0 PID: 24 Comm: kworker/0:1 Not tainted 4.17.0-rc6+ #68
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS
Google 01/01/2011
Workqueue: events rtc_timer_do_work
Call Trace:
<IRQ>
__dump_stack lib/dump_stack.c:77 [inline]
dump_stack+0x1b9/0x294 lib/dump_stack.c:113
nmi_cpu_backtrace.cold.4+0x19/0xce lib/nmi_backtrace.c:103
nmi_trigger_cpumask_backtrace+0x151/0x192 lib/nmi_backtrace.c:62
arch_trigger_cpumask_backtrace+0x14/0x20 arch/x86/kernel/apic/hw_nmi.c:38
trigger_single_cpu_backtrace include/linux/nmi.h:156 [inline]
rcu_dump_cpu_stacks+0x175/0x1c2 kernel/rcu/tree.c:1376
print_cpu_stall kernel/rcu/tree.c:1525 [inline]
check_cpu_stall.isra.61.cold.80+0x36c/0x59a kernel/rcu/tree.c:1593
__rcu_pending kernel/rcu/tree.c:3356 [inline]
rcu_pending kernel/rcu/tree.c:3401 [inline]
rcu_check_callbacks+0x21b/0xad0 kernel/rcu/tree.c:2763
update_process_times+0x2d/0x70 kernel/time/timer.c:1636
tick_sched_handle+0x9f/0x180 kernel/time/tick-sched.c:164
tick_sched_timer+0x45/0x130 kernel/time/tick-sched.c:1274
__run_hrtimer kernel/time/hrtimer.c:1398 [inline]
__hrtimer_run_queues+0x3e3/0x10a0 kernel/time/hrtimer.c:1460
hrtimer_interrupt+0x2f3/0x750 kernel/time/hrtimer.c:1518
local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1025 [inline]
smp_apic_timer_interrupt+0x15d/0x710 arch/x86/kernel/apic/apic.c:1050
apic_timer_interrupt+0xf/0x20 arch/x86/entry/entry_64.S:863
</IRQ>
RIP: 0010:trace_rtc_timer_enqueue include/trace/events/rtc.h:182 [inline]
RIP: 0010:rtc_timer_do_work+0xb2e/0x11f0 drivers/rtc/interface.c:985
RSP: 0018:ffff8801d94373a0 EFLAGS: 00000246 ORIG_RAX: ffffffffffffff13
RAX: 0000000000000001 RBX: ffff8801ce765901 RCX: ffffffff85459e03
RDX: 0000000000000000 RSI: ffffffff85459e10 RDI: ffff8801d9428e74
RBP: ffff8801d9437740 R08: ffff8801d9428640 R09: ffffed003b5c46d2
R10: ffffed003b5c46d2 R11: ffff8801dae23693 R12: 0000000000000001
R13: ffff8801ce7659f8 R14: dffffc0000000000 R15: 000000003b9aca00
process_one_work+0xc1e/0x1b50 kernel/workqueue.c:2145
worker_thread+0x1cc/0x1440 kernel/workqueue.c:2279
kthread+0x345/0x410 kernel/kthread.c:240
ret_from_fork+0x3a/0x50 arch/x86/entry/entry_64.S:412


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[syzbot]

Auto-closing this bug as obsolete.
Crashes did not happen for a while, no reproducer and no activity.