INFO: rcu detected stall in igmp_ifc_timer_expire

[syzbot]

Hello,

syzbot found the following crash on:

HEAD commit: b71acb0e3721 Merge branch 'linus' of git://git.kernel.org/..
git tree: net-next
console output: https://syzkaller.appspot.com/x/log.txt?x=1270bbdd400000
kernel config: https://syzkaller.appspot.com/x/.config?x=fbee5876573727cd
dashboard link: https://syzkaller.appspot.com/bug?extid=041483004a7f45f1f20a
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:
Reported-by: syzbot+041483...@syzkaller.appspotmail.com

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:
<IRQ>
__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
</IRQ>
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


---
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[syzbot]

syzbot has found a reproducer for the following crash on:

HEAD commit: 1e3778cb Merge tag 'scsi-fixes' of git://git.kernel.org/pu..
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=12df164e600000
kernel config: https://syzkaller.appspot.com/x/.config?x=b89bb446a3faaba4
dashboard link: https://syzkaller.appspot.com/bug?extid=041483004a7f45f1f20a
compiler: gcc (GCC) 9.0.0 20181231 (experimental)
syz repro: https://syzkaller.appspot.com/x/repro.syz?x=148c3001600000
C reproducer: https://syzkaller.appspot.com/x/repro.c?x=13b12cd1600000

IMPORTANT: if you fix the bug, please add the following tag to the commit:
Reported-by: syzbot+041483...@syzkaller.appspotmail.com

rcu: INFO: rcu_preempt self-detected stall on CPU

rcu: 1-...!: (1 GPs behind) idle=b8e/0/0x3 softirq=12119/12122 fqs=6
(t=10500 jiffies g=10289 q=55)
rcu: rcu_preempt kthread starved for 10480 jiffies! g10289 f0x0
RCU_GP_WAIT_FQS(5) ->state=0x402 ->cpu=0

rcu: RCU grace-period kthread stack dump:

rcu_preempt I29520 10 2 0x80004000
Call Trace:
context_switch kernel/sched/core.c:3254 [inline]
__schedule+0x755/0x1580 kernel/sched/core.c:3880
schedule+0xd9/0x260 kernel/sched/core.c:3947
schedule_timeout+0x486/0xc50 kernel/time/timer.c:1807
rcu_gp_fqs_loop kernel/rcu/tree.c:1611 [inline]
rcu_gp_kthread+0x9b2/0x18c0 kernel/rcu/tree.c:1768
kthread+0x361/0x430 kernel/kthread.c:255
ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:352
NMI backtrace for cpu 1
CPU: 1 PID: 0 Comm: swapper/1 Not tainted 5.3.0-rc7+ #0

Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS
Google 01/01/2011

Call Trace:
<IRQ>
__dump_stack lib/dump_stack.c:77 [inline]

dump_stack+0x172/0x1f0 lib/dump_stack.c:113
nmi_cpu_backtrace.cold+0x70/0xb2 lib/nmi_backtrace.c:101
nmi_trigger_cpumask_backtrace+0x23b/0x28b 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+0x183/0x1cf kernel/rcu/tree_stall.h:254
print_cpu_stall kernel/rcu/tree_stall.h:455 [inline]
check_cpu_stall kernel/rcu/tree_stall.h:529 [inline]
rcu_pending kernel/rcu/tree.c:2736 [inline]
rcu_sched_clock_irq.cold+0x4dd/0xc13 kernel/rcu/tree.c:2183
update_process_times+0x32/0x80 kernel/time/timer.c:1639
tick_sched_handle+0xa2/0x190 kernel/time/tick-sched.c:167
tick_sched_timer+0x53/0x140 kernel/time/tick-sched.c:1296
__run_hrtimer kernel/time/hrtimer.c:1389 [inline]
__hrtimer_run_queues+0x364/0xe40 kernel/time/hrtimer.c:1451
hrtimer_interrupt+0x314/0x770 kernel/time/hrtimer.c:1509
local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1106 [inline]
smp_apic_timer_interrupt+0x160/0x610 arch/x86/kernel/apic/apic.c:1131
apic_timer_interrupt+0xf/0x20 arch/x86/entry/entry_64.S:830
RIP: 0010:__list_del_entry_valid+0xb3/0xf5 lib/list_debug.c:54
Code: 75 53 49 8b 14 24 4c 39 f2 0f 85 99 00 00 00 49 8d 7d 08 48 b8 00 00
00 00 00 fc ff df 48 89 fa 48 c1 ea 03 80 3c 02 00 75 24 <49> 8b 55 08 4c
39 f2 0f 85 aa 00 00 00 41 5c b8 01 00 00 00 41 5d
RSP: 0018:ffff8880ae909010 EFLAGS: 00000246 ORIG_RAX: ffffffffffffff13
RAX: dffffc0000000000 RBX: ffff88808c064338 RCX: ffffffff85c65b39
RDX: 1ffff1101180c87b RSI: ffffffff85c66006 RDI: ffff88808c0643d8
RBP: ffff8880ae909028 R08: ffff8880a98d6340 R09: 0000000000000000
R10: fffffbfff134afaf R11: ffff8880a98d6340 R12: ffff88808c0643d0
R13: ffff88808c0643d0 R14: ffff88808c064338 R15: 0000000000000000
__list_del_entry include/linux/list.h:131 [inline]
list_move_tail include/linux/list.h:213 [inline]
hhf_dequeue+0x5c5/0xa20 net/sched/sch_hhf.c:439
dequeue_skb net/sched/sch_generic.c:258 [inline]
qdisc_restart net/sched/sch_generic.c:361 [inline]
__qdisc_run+0x1e7/0x19d0 net/sched/sch_generic.c:379
__dev_xmit_skb net/core/dev.c:3533 [inline]
__dev_queue_xmit+0x16f1/0x3650 net/core/dev.c:3838
dev_queue_xmit+0x18/0x20 net/core/dev.c:3902
br_dev_queue_push_xmit+0x3f3/0x5c0 net/bridge/br_forward.c:52
NF_HOOK include/linux/netfilter.h:305 [inline]
NF_HOOK include/linux/netfilter.h:299 [inline]
br_forward_finish+0xfa/0x400 net/bridge/br_forward.c:65
NF_HOOK include/linux/netfilter.h:305 [inline]
NF_HOOK include/linux/netfilter.h:299 [inline]
__br_forward+0x641/0xb00 net/bridge/br_forward.c:109
deliver_clone+0x61/0xc0 net/bridge/br_forward.c:125
maybe_deliver+0x2c7/0x390 net/bridge/br_forward.c:181
br_flood+0x13a/0x3d0 net/bridge/br_forward.c:223
br_dev_xmit+0x98c/0x15a0 net/bridge/br_device.c:100
__netdev_start_xmit include/linux/netdevice.h:4406 [inline]
netdev_start_xmit include/linux/netdevice.h:4420 [inline]
xmit_one net/core/dev.c:3280 [inline]
dev_hard_start_xmit+0x1a3/0x9c0 net/core/dev.c:3296
__dev_queue_xmit+0x2b15/0x3650 net/core/dev.c:3869
dev_queue_xmit+0x18/0x20 net/core/dev.c:3902
neigh_hh_output include/net/neighbour.h:500 [inline]
neigh_output include/net/neighbour.h:509 [inline]
ip_finish_output2+0x1726/0x2570 net/ipv4/ip_output.c:228
__ip_finish_output net/ipv4/ip_output.c:308 [inline]
__ip_finish_output+0x5fc/0xb90 net/ipv4/ip_output.c:290
ip_finish_output+0x38/0x1f0 net/ipv4/ip_output.c:318
NF_HOOK_COND include/linux/netfilter.h:294 [inline]
ip_output+0x21f/0x640 net/ipv4/ip_output.c:432
dst_output include/net/dst.h:436 [inline]
ip_local_out+0xbb/0x190 net/ipv4/ip_output.c:125
igmpv3_sendpack+0x1b5/0x2c0 net/ipv4/igmp.c:426
igmpv3_send_cr net/ipv4/igmp.c:721 [inline]
igmp_ifc_timer_expire+0x687/0xa00 net/ipv4/igmp.c:809
call_timer_fn+0x1ac/0x780 kernel/time/timer.c:1322
expire_timers kernel/time/timer.c:1366 [inline]
__run_timers kernel/time/timer.c:1685 [inline]
__run_timers kernel/time/timer.c:1653 [inline]
run_timer_softirq+0x697/0x17a0 kernel/time/timer.c:1698
__do_softirq+0x262/0x98c kernel/softirq.c:292
invoke_softirq kernel/softirq.c:373 [inline]
irq_exit+0x19b/0x1e0 kernel/softirq.c:413
exiting_irq arch/x86/include/asm/apic.h:537 [inline]
smp_apic_timer_interrupt+0x1a3/0x610 arch/x86/kernel/apic/apic.c:1133
apic_timer_interrupt+0xf/0x20 arch/x86/entry/entry_64.S:830
</IRQ>
RIP: 0010:native_safe_halt+0xe/0x10 arch/x86/include/asm/irqflags.h:61
Code: 38 73 6e fa eb 8a 90 90 90 90 90 90 e9 07 00 00 00 0f 00 2d 24 1b 4a
00 f4 c3 66 90 e9 07 00 00 00 0f 00 2d 14 1b 4a 00 fb f4 <c3> 90 55 48 89
e5 41 57 41 56 41 55 41 54 53 e8 ee 32 22 fa e8 39
RSP: 0018:ffff8880a98e7d68 EFLAGS: 00000286 ORIG_RAX: ffffffffffffff13
RAX: 1ffffffff11a5e8d RBX: ffff8880a98d6340 RCX: 1ffffffff134b5ee
RDX: dffffc0000000000 RSI: ffffffff8177f14e RDI: ffffffff873e050c
RBP: ffff8880a98e7d98 R08: ffff8880a98d6340 R09: ffffed101531ac69
R10: ffffed101531ac68 R11: ffff8880a98d6347 R12: dffffc0000000000
R13: ffffffff89a57d78 R14: 0000000000000000 R15: 0000000000000001
arch_cpu_idle+0xa/0x10 arch/x86/kernel/process.c:571
default_idle_call+0x84/0xb0 kernel/sched/idle.c:94
cpuidle_idle_call kernel/sched/idle.c:154 [inline]
do_idle+0x413/0x760 kernel/sched/idle.c:263
cpu_startup_entry+0x1b/0x20 kernel/sched/idle.c:354
start_secondary+0x315/0x430 arch/x86/kernel/smpboot.c:264
secondary_startup_64+0xa4/0xb0 arch/x86/kernel/head_64.S:241