syzbot


INFO: rcu detected stall in mld_ifc_timer_expire

Status: fixed on 2019/10/09 10:54
Reported-by: syzbot+bc6297c11f19ee807dc2@syzkaller.appspotmail.com
Fix commit: d4d6ec6dac07 sch_hhf: ensure quantum and hhf_non_hh_weight are non-zero
First crash: 1023d, last: 1014d

Cause bisection: the issue happens on the oldest tested release (bisect log)
Crash: no output from test machine (log)
Repro: C syz .config
similar bugs (4):
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream INFO: rcu detected stall in mld_ifc_timer_expire (3) 1 749d 749d 0/22 auto-closed as invalid on 2020/09/04 20:48
linux-4.19 INFO: rcu detected stall in mld_ifc_timer_expire C done 33 1010d 1022d 1/1 fixed on 2019/12/07 19:18
linux-4.14 INFO: rcu detected stall in mld_ifc_timer_expire C done 9 1013d 1022d 1/1 fixed on 2019/12/06 15:57
upstream INFO: rcu detected stall in mld_ifc_timer_expire (2) 1 934d 934d 0/22 closed as invalid on 2019/12/04 14:04

Sample crash report:
rcu: INFO: rcu_preempt self-detected stall on CPU
rcu: 	1-...!: (1 GPs behind) idle=632/0/0x3 softirq=9628/9631 fqs=22 
	(t=10501 jiffies g=9757 q=195)
rcu: rcu_preempt kthread starved for 10458 jiffies! g9757 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402 ->cpu=0
rcu: RCU grace-period kthread stack dump:
rcu_preempt     I29320    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-rc8+ #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:1110 [inline]
 smp_apic_timer_interrupt+0x160/0x610 arch/x86/kernel/apic/apic.c:1135
 apic_timer_interrupt+0xf/0x20 arch/x86/entry/entry_64.S:830
RIP: 0010:__read_once_size include/linux/compiler.h:199 [inline]
RIP: 0010:list_empty include/linux/list.h:268 [inline]
RIP: 0010:hhf_dequeue+0x506/0xa20 net/sched/sch_hhf.c:429
Code: 00 0f 85 35 04 00 00 4c 89 f8 4c 89 7b 08 48 c1 e8 03 42 80 3c 20 00 0f 85 12 04 00 00 49 89 1f e9 4b fb ff ff e8 7a 05 ac fb <48> 8b 45 b8 4c 8b 75 c8 42 80 3c 20 00 0f 85 3a 04 00 00 49 8b 85
RSP: 0018:ffff8880ae908f28 EFLAGS: 00000206 ORIG_RAX: ffffffffffffff13
RAX: ffff8880a98c6340 RBX: ffff88809290f9b8 RCX: ffffffff85c670f9
RDX: 0000000000000100 RSI: ffffffff85c66f86 RDI: ffff88809290f9c0
RBP: ffff8880ae908f78 R08: ffff8880a98c6340 R09: 0000000000000000
R10: fffffbfff134afaf R11: ffff8880a98c6340 R12: dffffc0000000000
R13: ffff88809290f6c0 R14: ffff88809290fa40 R15: ffff88809290fa50
 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]
 ip6_finish_output2+0xf58/0x2520 net/ipv6/ip6_output.c:116
 __ip6_finish_output+0x444/0xa50 net/ipv6/ip6_output.c:142
 ip6_finish_output+0x38/0x1f0 net/ipv6/ip6_output.c:152
 NF_HOOK_COND include/linux/netfilter.h:294 [inline]
 ip6_output+0x235/0x7c0 net/ipv6/ip6_output.c:175
 dst_output include/net/dst.h:436 [inline]
 NF_HOOK include/linux/netfilter.h:305 [inline]
 NF_HOOK include/linux/netfilter.h:299 [inline]
 mld_sendpack+0x9c7/0xea0 net/ipv6/mcast.c:1682
 mld_send_cr net/ipv6/mcast.c:1978 [inline]
 mld_ifc_timer_expire+0x449/0x8a0 net/ipv6/mcast.c:2477
 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:1137
 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: 88 63 6e fa eb 8a 90 90 90 90 90 90 e9 07 00 00 00 0f 00 2d 24 0b 4a 00 f4 c3 66 90 e9 07 00 00 00 0f 00 2d 14 0b 4a 00 fb f4 <c3> 90 55 48 89 e5 41 57 41 56 41 55 41 54 53 e8 2e 23 22 fa e8 f9
RSP: 0018:ffff8880a98dfd68 EFLAGS: 00000286 ORIG_RAX: ffffffffffffff13
RAX: 1ffffffff11a5e8d RBX: ffff8880a98c6340 RCX: 1ffffffff134b5ee
RDX: dffffc0000000000 RSI: ffffffff8177f15e RDI: ffffffff873e150c
RBP: ffff8880a98dfd98 R08: ffff8880a98c6340 R09: ffffed1015318c69
R10: ffffed1015318c68 R11: ffff8880a98c6347 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

Crashes (152):
Manager Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Title
ci-upstream-kasan-gce 2019/09/14 19:28 upstream a7f89616b737 32d59357 .config log report syz C
ci-upstream-kasan-gce-smack-root 2019/09/14 17:53 upstream a7f89616b737 32d59357 .config log report syz C
ci-upstream-kasan-gce-root 2019/09/14 17:40 upstream a7f89616b737 32d59357 .config log report syz C
ci-upstream-kasan-gce 2019/09/14 17:04 upstream a7f89616b737 32d59357 .config log report syz C
ci-upstream-kasan-gce-smack-root 2019/09/14 15:19 upstream a7f89616b737 32d59357 .config log report syz C
ci-upstream-kasan-gce-root 2019/09/14 13:03 upstream a7f89616b737 32d59357 .config log report syz C
ci-upstream-kasan-gce 2019/09/14 09:06 upstream a7f89616b737 32d59357 .config log report syz C
ci-upstream-kasan-gce-root 2019/09/14 08:44 upstream a7f89616b737 32d59357 .config log report syz C
ci-upstream-kasan-gce 2019/09/14 07:21 upstream a7f89616b737 32d59357 .config log report syz C
ci-upstream-kasan-gce-selinux-root 2019/09/14 07:11 upstream a7f89616b737 32d59357 .config log report syz C
ci-upstream-kasan-gce 2019/09/14 05:41 upstream a7f89616b737 32d59357 .config log report syz C
ci-upstream-kasan-gce-root 2019/09/14 04:10 upstream a7f89616b737 32d59357 .config log report syz C
ci-upstream-kasan-gce-smack-root 2019/09/14 04:10 upstream a7f89616b737 32d59357 .config log report syz C
ci-upstream-kasan-gce 2019/09/14 02:47 upstream a7f89616b737 32d59357 .config log report syz C
ci-upstream-kasan-gce-root 2019/09/13 23:15 upstream a7f89616b737 32d59357 .config log report syz C
ci-upstream-kasan-gce 2019/09/13 15:01 upstream 505a8ec7e11a 40fa42bc .config log report syz C
ci-upstream-kasan-gce-root 2019/09/13 14:30 upstream 505a8ec7e11a 40fa42bc .config log report syz C
ci-upstream-kasan-gce 2019/09/13 10:28 upstream 505a8ec7e11a 40fa42bc .config log report syz C
ci-upstream-kasan-gce-smack-root 2019/09/13 07:11 upstream 505a8ec7e11a 40fa42bc .config log report syz C
ci-upstream-kasan-gce-smack-root 2019/09/13 01:02 upstream ad32b4800c2b 0b7672ee .config log report syz C
ci-upstream-kasan-gce 2019/09/12 23:38 upstream ad32b4800c2b 0b7672ee .config log report syz C
ci-upstream-kasan-gce-selinux-root 2019/09/12 19:05 upstream ad32b4800c2b 0b7672ee .config log report syz C
ci-upstream-kasan-gce 2019/09/12 18:14 upstream ad32b4800c2b 0b7672ee .config log report syz C
ci-upstream-kasan-gce-smack-root 2019/09/12 17:00 upstream ad32b4800c2b 0b7672ee .config log report syz C
ci-upstream-kasan-gce-selinux-root 2019/09/12 12:24 upstream 3120b9a6a3f7 f4e53c10 .config log report syz C
ci-upstream-kasan-gce 2019/09/12 12:21 upstream 3120b9a6a3f7 f4e53c10 .config log report syz C
ci-upstream-kasan-gce-selinux-root 2019/09/12 10:39 upstream 3120b9a6a3f7 f4e53c10 .config log report syz C
ci-upstream-kasan-gce-selinux-root 2019/09/12 07:27 upstream 3120b9a6a3f7 f4e53c10 .config log report syz C
ci-upstream-kasan-gce-selinux-root 2019/09/12 01:48 upstream 3120b9a6a3f7 f4e53c10 .config log report syz C
ci-upstream-kasan-gce 2019/09/12 01:35 upstream 3120b9a6a3f7 f4e53c10 .config log report syz C
ci-upstream-kasan-gce-smack-root 2019/09/11 19:02 upstream 3120b9a6a3f7 a60cb4cd .config log report syz C
ci-upstream-kasan-gce-selinux-root 2019/09/11 11:39 upstream 3120b9a6a3f7 a60cb4cd .config log report syz C
ci-upstream-kasan-gce-smack-root 2019/09/06 16:14 upstream 3b47fd5ca9ea 040fda58 .config log report syz C
ci-upstream-kasan-gce-386 2019/09/14 20:06 upstream a7f89616b737 32d59357 .config log report syz C
ci-upstream-kasan-gce-386 2019/09/14 14:27 upstream a7f89616b737 32d59357 .config log report syz C
ci-upstream-kasan-gce-386 2019/09/14 05:34 upstream a7f89616b737 32d59357 .config log report syz C
ci-upstream-kasan-gce-386 2019/09/13 19:07 upstream 505a8ec7e11a 40fa42bc .config log report syz C
ci-upstream-kasan-gce-386 2019/09/12 22:01 upstream ad32b4800c2b 0b7672ee .config log report syz C
ci-upstream-kasan-gce-386 2019/09/12 19:19 upstream ad32b4800c2b 0b7672ee .config log report syz C
ci-upstream-kasan-gce-386 2019/09/12 06:32 upstream 3120b9a6a3f7 f4e53c10 .config log report syz C
ci-upstream-kasan-gce-386 2019/09/11 19:02 upstream 3120b9a6a3f7 a60cb4cd .config log report syz C
ci-upstream-net-this-kasan-gce 2019/09/10 20:03 net c8dc55956b09 a60cb4cd .config log report syz C
ci-upstream-net-kasan-gce 2019/09/16 01:24 net-next a3d3c74da49c 32d59357 .config log report syz C
ci-upstream-net-kasan-gce 2019/09/15 11:02 net-next 1ba569fc2250 32d59357 .config log report syz C
ci-upstream-net-kasan-gce 2019/09/15 09:12 net-next 1ba569fc2250 32d59357 .config log report syz C
ci-upstream-net-kasan-gce 2019/09/14 19:15 net-next 1ba569fc2250 32d59357 .config log report syz C
ci-upstream-net-kasan-gce 2019/09/11 19:54 net-next 747f3cf4bf71 a60cb4cd .config log report syz C
ci-upstream-linux-next-kasan-gce-root 2019/09/14 17:22 linux-next 6d028043b55e 32d59357 .config log report syz C
ci-upstream-linux-next-kasan-gce-root 2019/09/14 08:35 linux-next 6d028043b55e 32d59357 .config log report syz C
ci-upstream-linux-next-kasan-gce-root 2019/09/11 11:14 linux-next 6d028043b55e a60cb4cd .config log report syz C
ci-upstream-kasan-gce-selinux-root 2019/09/13 08:36 upstream 505a8ec7e11a 40fa42bc .config log report
ci-upstream-kasan-gce 2019/09/13 05:33 upstream 505a8ec7e11a 40fa42bc .config log report
ci-upstream-kasan-gce-root 2019/09/11 20:59 upstream 3120b9a6a3f7 f4e53c10 .config log report
ci-upstream-kasan-gce 2019/09/11 17:55 upstream 3120b9a6a3f7 a60cb4cd .config log report
ci-upstream-kasan-gce 2019/09/09 05:59 upstream f74c2bb98776 a60cb4cd .config log report
ci-upstream-kasan-gce 2019/09/06 20:44 upstream 044597100037 a60cb4cd .config log report
ci-upstream-kasan-gce-386 2019/09/13 20:37 upstream a7f89616b737 32d59357 .config log report
ci-upstream-net-this-kasan-gce 2019/09/09 07:47 net 28abe5796252 a60cb4cd .config log report
ci-upstream-net-this-kasan-gce 2019/09/06 15:18 net 7bdf4de12677 040fda58 .config log report
ci-upstream-net-kasan-gce 2019/09/15 07:02 net-next 1ba569fc2250 32d59357 .config log report
ci-upstream-net-kasan-gce 2019/09/13 17:17 net-next 022c10d6c73b 40fa42bc .config log report
ci-upstream-net-kasan-gce 2019/09/13 14:09 net-next 022c10d6c73b 40fa42bc .config log report
ci-upstream-net-kasan-gce 2019/09/09 00:16 net-next 6703a605b5ab a60cb4cd .config log report
ci-upstream-net-kasan-gce 2019/09/08 19:04 net-next 6703a605b5ab a60cb4cd .config log report
ci-upstream-net-kasan-gce 2019/09/08 16:27 net-next 6703a605b5ab a60cb4cd .config log report
ci-upstream-net-kasan-gce 2019/09/07 23:42 net-next 742ca7812bcc a60cb4cd .config log report