[lkml]   [2018]   [Dec]   [30]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
Messages in this thread
SubjectINFO: rcu detected stall in igmp_ifc_timer_expire

syzbot found the following crash on:

HEAD commit: b71acb0e3721 Merge branch 'linus' of git://
git tree: net-next
console output:
kernel config:
dashboard link:
compiler: gcc (GCC) 8.0.1 20180413 (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:

rcu: INFO: rcu_preempt self-detected stall on CPU
rcu: 0-...!: (1 GPs behind) idle=f3e/1/0x4000000000000004
softirq=83230/83231 fqs=14
rcu: (t=10501 jiffies g=106569 q=897)
rcu: rcu_preempt kthread starved for 10474 jiffies! g106569 f0x0
RCU_GP_WAIT_FQS(5) ->state=0x402 ->cpu=1
rcu: RCU grace-period kthread stack dump:
rcu_preempt I22032 10 2 0x80000000
Call Trace:
context_switch kernel/sched/core.c:2831 [inline]
__schedule+0x86c/0x1ed0 kernel/sched/core.c:3472
schedule+0xfe/0x460 kernel/sched/core.c:3516
schedule_timeout+0x140/0x260 kernel/time/timer.c:1803
rcu_gp_fqs_loop+0x762/0xa80 kernel/rcu/tree.c:1948
rcu_gp_kthread+0x341/0xc70 kernel/rcu/tree.c:2105
kthread+0x35a/0x440 kernel/kthread.c:246
ret_from_fork+0x3a/0x50 arch/x86/entry/entry_64.S:352
NMI backtrace for cpu 0
CPU: 0 PID: 5 Comm: kworker/0:0 Not tainted 4.20.0+ #362
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS
Google 01/01/2011
Workqueue: rcu_gp process_srcu
Call Trace:
__dump_stack lib/dump_stack.c:77 [inline]
dump_stack+0x1d3/0x2c6 lib/dump_stack.c:113
nmi_cpu_backtrace.cold.4+0x63/0xa2 lib/nmi_backtrace.c:101
nmi_trigger_cpumask_backtrace+0x1c2/0x22c 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:164 [inline]
rcu_dump_cpu_stacks+0x16f/0x1bc kernel/rcu/tree.c:1211
print_cpu_stall.cold.68+0x218/0x40a kernel/rcu/tree.c:1348
check_cpu_stall kernel/rcu/tree.c:1422 [inline]
rcu_pending kernel/rcu/tree.c:3018 [inline]
rcu_check_callbacks+0xac1/0x1410 kernel/rcu/tree.c:2521
update_process_times+0x2d/0x70 kernel/time/timer.c:1635
tick_sched_handle+0x9f/0x180 kernel/time/tick-sched.c:161
tick_sched_timer+0x45/0x130 kernel/time/tick-sched.c:1271
__run_hrtimer kernel/time/hrtimer.c:1389 [inline]
__hrtimer_run_queues+0x41c/0x10d0 kernel/time/hrtimer.c:1451
hrtimer_interrupt+0x313/0x780 kernel/time/hrtimer.c:1509
local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1035 [inline]
smp_apic_timer_interrupt+0x1a1/0x760 arch/x86/kernel/apic/apic.c:1060
apic_timer_interrupt+0xf/0x20 arch/x86/entry/entry_64.S:807
RIP: 0010:__sanitizer_cov_trace_const_cmp8+0x4/0x20 kernel/kcov.c:195
Code: 66 0f 1f 44 00 00 55 89 f2 89 fe bf 05 00 00 00 48 89 e5 48 8b 4d 08
e8 6a fe ff ff 5d c3 0f 1f 84 00 00 00 00 00 55 48 89 f2 <48> 89 fe bf 07
00 00 00 48 89 e5 48 8b 4d 08 e8 48 fe ff ff 5d c3
RSP: 0018:ffff8880ae606cb8 EFLAGS: 00000246 ORIG_RAX: ffffffffffffff13
RAX: ffffed1015cc0dd7 RBX: 0000000000000000 RCX: ffffffff86c3afc1
RDX: ffff888062f97208 RSI: ffff888062f97208 RDI: 0000000000000000
RBP: ffff8880ae606f80 R08: ffff8880a9de6140 R09: 0000000000000000
R10: 0000000000000000 R11: ffff8880a9de6140 R12: ffff888062f97208
R13: dffffc0000000000 R14: ffff888062f97200 R15: 00000000ffffffff
xfrm_policy_lookup+0x7e/0x80 net/xfrm/xfrm_policy.c:2145
xfrm_bundle_lookup net/xfrm/xfrm_policy.c:2939 [inline]
xfrm_lookup_with_ifid+0x972/0x2b80 net/xfrm/xfrm_policy.c:3080
xfrm_lookup net/xfrm/xfrm_policy.c:3172 [inline]
xfrm_lookup_route+0x3c/0x1f0 net/xfrm/xfrm_policy.c:3183
ip_route_output_flow+0xb1/0xc0 net/ipv4/route.c:2582
ip_route_output_ports include/net/route.h:161 [inline]
igmpv3_newpack+0x541/0x1430 net/ipv4/igmp.c:362
add_grhead.isra.29+0x235/0x300 net/ipv4/igmp.c:433
add_grec+0x106b/0x1350 net/ipv4/igmp.c:566
igmpv3_send_cr net/ipv4/igmp.c:696 [inline]
igmp_ifc_timer_expire+0x5d2/0xbe0 net/ipv4/igmp.c:793
call_timer_fn+0x272/0x920 kernel/time/timer.c:1325
expire_timers kernel/time/timer.c:1362 [inline]
__run_timers+0x7e5/0xc70 kernel/time/timer.c:1681
run_timer_softirq+0x52/0xb0 kernel/time/timer.c:1694
__do_softirq+0x30c/0xb2e kernel/softirq.c:292
invoke_softirq kernel/softirq.c:373 [inline]
irq_exit+0x17f/0x1c0 kernel/softirq.c:413
exiting_irq arch/x86/include/asm/apic.h:536 [inline]
smp_apic_timer_interrupt+0x1cb/0x760 arch/x86/kernel/apic/apic.c:1062
apic_timer_interrupt+0xf/0x20 arch/x86/entry/entry_64.S:807
RIP: 0010:rdtsc arch/x86/include/asm/msr.h:207 [inline]
RIP: 0010:rdtsc_ordered arch/x86/include/asm/msr.h:232 [inline]
RIP: 0010:delay_tsc+0x4c/0xc0 arch/x86/lib/delay.c:61
Code: e8 0f 31 48 c1 e2 20 48 09 c2 49 89 d4 eb 16 f3 90 bf 01 00 00 00 e8
33 1a 71 f9 e8 4e 9c ab fb 44 39 f0 75 36 0f ae e8 0f 31 <48> c1 e2 20 48
89 d3 48 09 c3 48 89 d8 4c 29 e0 4c 39 e8 73 24 bf
RSP: 0018:ffff8880a9dff128 EFLAGS: 00000246 ORIG_RAX: ffffffffffffff13
RAX: 00000000e5a9cbe0 RBX: 0000014ce5a9cb06 RCX: ffffffff839297ca
RDX: 000000000000014c RSI: ffffffff839297d8 RDI: 0000000000000005
RBP: ffff8880a9dff148 R08: ffff8880a9de6140 R09: 1ffffd1ffffa0e00
R10: ffff8880a9dff250 R11: ffffffff8b33a227 R12: 0000014ce5a9b8f7
R13: 0000000000002ced R14: 0000000000000000 R15: ffffffff8b339e80
__delay arch/x86/lib/delay.c:161 [inline]
__const_udelay+0x62/0x80 arch/x86/lib/delay.c:175
try_check_zero+0x384/0x5f0 kernel/rcu/srcutree.c:730
srcu_advance_state kernel/rcu/srcutree.c:1167 [inline]
process_srcu+0x6bf/0x1460 kernel/rcu/srcutree.c:1261
process_one_work+0xc90/0x1c40 kernel/workqueue.c:2153
worker_thread+0x17f/0x1390 kernel/workqueue.c:2296
kthread+0x35a/0x440 kernel/kthread.c:246
ret_from_fork+0x3a/0x50 arch/x86/entry/entry_64.S:352

This bug is generated by a bot. It may contain errors.
See for more information about syzbot.
syzbot engineers can be reached at

syzbot will keep track of this bug report. See: for how to communicate with

 \ /
  Last update: 2018-12-31 04:35    [W:0.036 / U:0.136 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site