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INFO: rcu detected stall in mld_ifc_timer_expire (2)

Status: closed as invalid on 2019/12/04 14:04
Subsystems: bridge
[Documentation on labels]
First crash: 2025d, last: 2025d
▶ ▼ 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 C done 152 2105d 2112d 13/29 fixed on 2019/10/09 10:54
upstream INFO: rcu detected stall in mld_ifc_timer_expire (3) net 1 1840d 1840d 0/29 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 2101d 2114d 1/1 fixed on 2019/12/07 19:18
linux-4.14 INFO: rcu detected stall in mld_ifc_timer_expire C done 9 2104d 2113d 1/1 fixed on 2019/12/06 15:57

Sample crash report:
hrtimer: interrupt took 36417 ns
rcu: INFO: rcu_preempt self-detected stall on CPU
rcu: 	0-....: (10488 ticks this GP) idle=24a/1/0x4000000000000004 softirq=9083/9083 fqs=3571 
	(t=10500 jiffies g=7853 q=366)
NMI backtrace for cpu 0
CPU: 0 PID: 8593 Comm: syz-executor.1 Not tainted 5.4.0-syzkaller #0
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS rel-1.12.0-59-gc9ba5276e321-prebuilt.qemu.org 04/01/2014
Call Trace:
 <IRQ>
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack+0x197/0x210 lib/dump_stack.c:118
 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:2827 [inline]
 rcu_sched_clock_irq.cold+0x509/0xc02 kernel/rcu/tree.c:2271
 update_process_times+0x2d/0x70 kernel/time/timer.c:1726
 tick_sched_handle+0xa2/0x190 kernel/time/tick-sched.c:167
 tick_sched_timer+0x53/0x140 kernel/time/tick-sched.c:1310
 __run_hrtimer kernel/time/hrtimer.c:1517 [inline]
 __hrtimer_run_queues+0x364/0xe40 kernel/time/hrtimer.c:1579
 hrtimer_interrupt+0x314/0x770 kernel/time/hrtimer.c:1641
 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:829
RIP: 0010:br_allowed_egress+0x0/0x980 net/bridge/br_vlan.c:553
Code: 8d 18 ff ff ff e8 40 3b d1 fa 8b 8d 18 ff ff ff e9 04 fc ff ff 48 8b bd f8 fe ff ff e8 09 3b d1 fa e9 73 fc ff ff 0f 1f 40 00 <55> 48 89 e5 41 57 48 8d 85 38 ff ff ff 41 56 48 c1 e8 03 41 55 49
RSP: 0018:ffffc90000007458 EFLAGS: 00010206 ORIG_RAX: ffffffffffffff13
RAX: ffff88806281c040 RBX: ffff888028c44800 RCX: 1ffff11005188901
RDX: 0000000000000100 RSI: ffff8880206b58c0 RDI: ffff88801dbbf800
RBP: ffffc90000007498 R08: ffff88806281c040 R09: ffffed1005a47045
R10: ffffed1005a47044 R11: ffff88802d238223 R12: 0000000000000000
R13: ffff8880206b58c0 R14: ffff888028c44820 R15: ffff88801dbbf800
 br_flood+0x13a/0x3d0 net/bridge/br_forward.c:223
 br_dev_xmit+0x98c/0x1590 net/bridge/br_device.c:98
 __netdev_start_xmit include/linux/netdevice.h:4442 [inline]
 netdev_start_xmit include/linux/netdevice.h:4456 [inline]
 xmit_one net/core/dev.c:3420 [inline]
 dev_hard_start_xmit+0x1a3/0x9b0 net/core/dev.c:3436
 __dev_queue_xmit+0x2b05/0x35c0 net/core/dev.c:4013
 dev_queue_xmit+0x18/0x20 net/core/dev.c:4046
 neigh_hh_output include/net/neighbour.h:500 [inline]
 neigh_output include/net/neighbour.h:509 [inline]
 ip6_finish_output2+0xfbe/0x25c0 net/ipv6/ip6_output.c:116
 __ip6_finish_output+0x444/0xaa0 net/ipv6/ip6_output.c:142
 ip6_finish_output+0x38/0x1f0 net/ipv6/ip6_output.c:152
 NF_HOOK_COND include/linux/netfilter.h:296 [inline]
 ip6_output+0x25e/0x880 net/ipv6/ip6_output.c:175
 dst_output include/net/dst.h:436 [inline]
 NF_HOOK include/linux/netfilter.h:307 [inline]
 NF_HOOK include/linux/netfilter.h:301 [inline]
 mld_sendpack+0x9c2/0xed0 net/ipv6/mcast.c:1682
 mld_send_cr net/ipv6/mcast.c:1978 [inline]
 mld_ifc_timer_expire+0x454/0x950 net/ipv6/mcast.c:2477
 call_timer_fn+0x1ac/0x780 kernel/time/timer.c:1404
 expire_timers kernel/time/timer.c:1449 [inline]
 __run_timers kernel/time/timer.c:1773 [inline]
 __run_timers kernel/time/timer.c:1740 [inline]
 run_timer_softirq+0x6c3/0x1790 kernel/time/timer.c:1786
 __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:536 [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:829
 </IRQ>
RIP: 0010:arch_local_irq_restore arch/x86/include/asm/paravirt.h:752 [inline]
RIP: 0010:generic_exec_single+0x33a/0x4c0 kernel/smp.c:155
Code: 00 fc ff df 48 c1 e8 03 80 3c 10 00 0f 85 68 01 00 00 48 83 3d 3e 5e 09 08 00 0f 84 e0 00 00 00 e8 9b 25 0b 00 48 89 df 57 9d <0f> 1f 44 00 00 45 31 ed e9 39 fe ff ff e8 84 25 0b 00 0f 0b e9 23
RSP: 0018:ffffc900009f7a60 EFLAGS: 00000212 ORIG_RAX: ffffffffffffff13
RAX: 0000000000040000 RBX: 0000000000000212 RCX: ffffc9000f9ec000
RDX: 000000000001a0a1 RSI: ffffffff8169d5a5 RDI: 0000000000000212
RBP: ffffc900009f7a90 R08: 1ffffffff16181b9 R09: fffffbfff16181ba
R10: fffffbfff16181b9 R11: ffffffff8b0c0dcf R12: 0000000000000200
R13: ffffc900009f7ae0 R14: ffffc900009f7bc0 R15: ffffffff818bef80
 smp_call_function_single+0x17c/0x480 kernel/smp.c:308
 task_function_call+0xe9/0x180 kernel/events/core.c:114
 perf_install_in_context+0x308/0x5a0 kernel/events/core.c:2746
 __do_sys_perf_event_open+0x1cbc/0x2c70 kernel/events/core.c:11543
 __se_sys_perf_event_open kernel/events/core.c:11151 [inline]
 __ia32_sys_perf_event_open+0xbd/0x140 kernel/events/core.c:11151
 do_syscall_32_irqs_on arch/x86/entry/common.c:337 [inline]
 do_fast_syscall_32+0x27b/0xe16 arch/x86/entry/common.c:408
 entry_SYSENTER_compat+0x70/0x7f arch/x86/entry/entry_64_compat.S:139
RIP: 0023:0xf7fa8a39
Code: 00 00 00 89 d3 5b 5e 5f 5d c3 b8 80 96 98 00 eb c4 8b 04 24 c3 8b 1c 24 c3 8b 34 24 c3 8b 3c 24 c3 51 52 55 89 e5 0f 34 cd 80 <5d> 5a 59 c3 90 90 90 90 eb 0d 90 90 90 90 90 90 90 90 90 90 90 90
RSP: 002b:00000000f5da40cc EFLAGS: 00000296 ORIG_RAX: 0000000000000150
RAX: ffffffffffffffda RBX: 0000000020000980 RCX: 0000000000000000
RDX: 0000000000000000 RSI: 00000000ffffffff RDI: 0000000000000000
RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2019/12/04 10:43 upstream 63de37476ebd 0ecb9746 .config console log report ci-qemu-upstream-386
* Struck through repros no longer work on HEAD.