INFO: rcu detected stall in call_timer_fn

[syzbot]

Hello,

syzbot found the following crash on:

HEAD commit: 4c5bf01e Linux 4.14.161
git tree: linux-4.14.y
console output: https://syzkaller.appspot.com/x/log.txt?x=169119fee00000
kernel config: https://syzkaller.appspot.com/x/.config?x=2f880a3dbba6d2e2
dashboard link: https://syzkaller.appspot.com/bug?extid=a9853ca066b9c66386a9
compiler: gcc (GCC) 9.0.0 20181231 (experimental)

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+a9853c...@syzkaller.appspotmail.com

8021q: adding VLAN 0 to HW filter on device batadv0
IPv6: ADDRCONF(NETDEV_UP): veth0_to_bridge: link is not ready
IPv6: ADDRCONF(NETDEV_UP): veth1_to_bridge: link is not ready
IPv6: ADDRCONF(NETDEV_CHANGE): veth0_to_hsr: link becomes ready
INFO: rcu_preempt detected stalls on CPUs/tasks:
(detected by 1, t=10502 jiffies, g=123587, c=123586, q=249)
All QSes seen, last rcu_preempt kthread activity 10502
(4295289044-4295278542), jiffies_till_next_fqs=1, root ->qsmask 0x0
syz-executor.5 R running task 29024 21375 21304 0x00000008
Call Trace:
<IRQ>
sched_show_task kernel/sched/core.c:5168 [inline]
sched_show_task.cold+0x2f0/0x351 kernel/sched/core.c:5143
print_other_cpu_stall kernel/rcu/tree.c:1501 [inline]
check_cpu_stall kernel/rcu/tree.c:1616 [inline]
__rcu_pending kernel/rcu/tree.c:3390 [inline]
rcu_pending kernel/rcu/tree.c:3452 [inline]
rcu_check_callbacks.cold+0xcb1/0xd0a kernel/rcu/tree.c:2792
update_process_times+0x31/0x70 kernel/time/timer.c:1590
tick_sched_handle+0x85/0x160 kernel/time/tick-sched.c:161
tick_sched_timer+0x43/0x130 kernel/time/tick-sched.c:1219
__run_hrtimer kernel/time/hrtimer.c:1220 [inline]
__hrtimer_run_queues+0x270/0xbc0 kernel/time/hrtimer.c:1284
hrtimer_interrupt+0x1d8/0x5d0 kernel/time/hrtimer.c:1318
local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1075 [inline]
smp_apic_timer_interrupt+0x11c/0x5e0 arch/x86/kernel/apic/apic.c:1100
apic_timer_interrupt+0x96/0xa0 arch/x86/entry/entry_64.S:792
RIP: 0010:arch_local_irq_restore arch/x86/include/asm/paravirt.h:779
[inline]
RIP: 0010:lock_acquire+0x1ea/0x430 kernel/locking/lockdep.c:3997
RSP: 0000:ffff8880aed07cf0 EFLAGS: 00000282 ORIG_RAX: ffffffffffffff10
RAX: 1ffffffff0fe2d29 RBX: ffff888097d6a1c0 RCX: 0000000002a75fde
RDX: dffffc0000000000 RSI: ffff888097d6aa40 RDI: 0000000000000282
RBP: ffff8880aed07d38 R08: 0000000000006670 R09: ffffffff89592dc0
R10: ffff888097d6aa40 R11: ffff888097d6a1c0 R12: ffff8880aed07d90
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000
call_timer_fn+0x114/0x670 kernel/time/timer.c:1276
expire_timers kernel/time/timer.c:1318 [inline]
__run_timers kernel/time/timer.c:1636 [inline]
__run_timers kernel/time/timer.c:1604 [inline]
run_timer_softirq+0x5b7/0x1520 kernel/time/timer.c:1649
__do_softirq+0x244/0x9a0 kernel/softirq.c:288
invoke_softirq kernel/softirq.c:368 [inline]
irq_exit+0x160/0x1b0 kernel/softirq.c:409
exiting_irq arch/x86/include/asm/apic.h:648 [inline]
smp_apic_timer_interrupt+0x146/0x5e0 arch/x86/kernel/apic/apic.c:1102
apic_timer_interrupt+0x96/0xa0 arch/x86/entry/entry_64.S:792
</IRQ>
RIP: 0033:0x45d82a
RSP: 002b:00007f945b8dac58 EFLAGS: 00000246 ORIG_RAX: ffffffffffffff10
RAX: 0000000000000000 RBX: 0000000000000000 RCX: 000000000045d82a
RDX: 0000000000003c12 RSI: 00007f945b8dac60 RDI: 0000000000000001
RBP: 000000000075bf20 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00000000004c151f R14: 00000000004d58d8 R15: 00000000ffffffff
rcu_preempt kthread starved for 10502 jiffies! g123587 c123586 f0x2
RCU_GP_WAIT_FQS(3) ->state=0x0 ->cpu=1
rcu_preempt R running task 29776 8 2 0x80000000
Call Trace:
context_switch kernel/sched/core.c:2808 [inline]
__schedule+0x7b8/0x1cd0 kernel/sched/core.c:3384
schedule+0x92/0x1c0 kernel/sched/core.c:3428
schedule_timeout+0x43e/0xe10 kernel/time/timer.c:1746
rcu_gp_kthread+0xbf4/0x1ec0 kernel/rcu/tree.c:2255
kthread+0x319/0x430 kernel/kthread.c:232
ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:404
IPv6: ADDRCONF(NETDEV_CHANGE): hsr_slave_0: link becomes ready
IPv6: ADDRCONF(NETDEV_CHANGE): vxcan1: link becomes ready
IPv6: ADDRCONF(NETDEV_CHANGE): vxcan0: link becomes ready
IPv6: ADDRCONF(NETDEV_CHANGE): veth0_to_bridge: link becomes ready
IPv6: ADDRCONF(NETDEV_CHANGE): bridge_slave_0: link becomes ready
bridge0: port 1(bridge_slave_0) entered blocking state
bridge0: port 1(bridge_slave_0) entered forwarding state
IPv6: ADDRCONF(NETDEV_CHANGE): veth1_to_bridge: link becomes ready
IPv6: ADDRCONF(NETDEV_CHANGE): bridge_slave_1: link becomes ready
bridge0: port 2(bridge_slave_1) entered blocking state
bridge0: port 2(bridge_slave_1) entered forwarding state
IPv6: ADDRCONF(NETDEV_CHANGE): bridge0: link becomes ready
device bridge_slave_1 left promiscuous mode
bridge0: port 2(bridge_slave_1) entered disabled state
device bridge_slave_0 left promiscuous mode
bridge0: port 1(bridge_slave_0) entered disabled state
device bridge_slave_1 left promiscuous mode
bridge0: port 2(bridge_slave_1) entered disabled state
device bridge_slave_0 left promiscuous mode
bridge0: port 1(bridge_slave_0) entered disabled state
device bridge_slave_1 left promiscuous mode
bridge0: port 2(bridge_slave_1) entered disabled state
device bridge_slave_0 left promiscuous mode
bridge0: port 1(bridge_slave_0) entered disabled state
device bridge_slave_1 left promiscuous mode
bridge0: port 2(bridge_slave_1) entered disabled state
device bridge_slave_0 left promiscuous mode
bridge0: port 1(bridge_slave_0) entered disabled state
device hsr_slave_1 left promiscuous mode
device hsr_slave_0 left promiscuous mode
team0 (unregistering): Port device team_slave_1 removed
team0 (unregistering): Port device team_slave_0 removed
bond0 (unregistering): Releasing backup interface bond_slave_1
bond0 (unregistering): Releasing backup interface bond_slave_0
bond0 (unregistering): Released all slaves
bond43 (unregistering): Released all slaves
bond42 (unregistering): Released all slaves
bond41 (unregistering): Released all slaves
bond40 (unregistering): Released all slaves
bond39 (unregistering): Released all slaves
bond38 (unregistering): Released all slaves
bond37 (unregistering): Released all slaves
bond36 (unregistering): Released all slaves
bond35 (unregistering): Released all slaves
bond34 (unregistering): Released all slaves
bond33 (unregistering): Released all slaves
bond32 (unregistering): Released all slaves
bond31 (unregistering): Released all slaves
bond30 (unregistering): Released all slaves
bond29 (unregistering): Released all slaves
bond28 (unregistering): Released all slaves
bond27 (unregistering): Released all slaves
bond26 (unregistering): Released all slaves
bond25 (unregistering): Released all slaves
bond24 (unregistering): Released all slaves
bond23 (unregistering): Released all slaves
bond22 (unregistering): Released all slaves
bond21 (unregistering): Released all slaves
bond20 (unregistering): Released all slaves
bond19 (unregistering): Released all slaves
bond18 (unregistering): Released all slaves
bond17 (unregistering): Released all slaves
bond16 (unregistering): Released all slaves
bond15 (unregistering): Released all slaves
bond14 (unregistering): Released all slaves
bond13 (unregistering): Released all slaves
bond12 (unregistering): Released all slaves
bond11 (unregistering): Released all slaves
bond10 (unregistering): Released all slaves
bond9 (unregistering): Released all slaves
bond8 (unregistering): Released all slaves
bond7 (unregistering): Released all slaves
bond6 (unregistering): Released all slaves
bond5 (unregistering): Released all slaves
bond4 (unregistering): Released all slaves
bond3 (unregistering): Released all slaves
bond2 (unregistering): Released all slaves
bond1 (unregistering): Released all slaves
device hsr_slave_1 left promiscuous mode
device hsr_slave_0 left promiscuous mode
team0 (unregistering): Port device team_slave_1 removed
team0 (unregistering): Port device team_slave_0 removed
bond0 (unregistering): Releasing backup interface bond_slave_1
bond0 (unregistering): Releasing backup interface bond_slave_0
bond0 (unregistering): Released all slaves
device hsr_slave_1 left promiscuous mode
device hsr_slave_0 left promiscuous mode
team0 (unregistering): Port device team_slave_1 removed
team0 (unregistering): Port device team_slave_0 removed
bond0 (unregistering): Releasing backup interface bond_slave_1
bond0 (unregistering): Releasing backup interface bond_slave_0
bond0 (unregistering): Released all slaves
bond3 (unregistering): Released all slaves
bond2 (unregistering): Released all slaves
bond1 (unregistering): Released all slaves
device hsr_slave_1 left promiscuous mode
device hsr_slave_0 left promiscuous mode
team0 (unregistering): Port device team_slave_1 removed
team0 (unregistering): Port device team_slave_0 removed
bond0 (unregistering): Releasing backup interface bond_slave_1
bond0 (unregistering): Releasing backup interface bond_slave_0
bond0 (unregistering): Released all slaves
IPVS: ftp: loaded support on port[0] = 21


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[syzbot]

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