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INFO: rcu detected stall in br_forward_delay_timer_expired

Status: closed as invalid on 2019/11/29 14:24
Subsystems: net
[Documentation on labels]
First crash: 2000d, last: 2000d
Similar bugs (2)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
linux-6.1 INFO: rcu detected stall in br_forward_delay_timer_expired (2) 1 82d 82d 0/3 upstream: reported on 2025/02/28 07:03
linux-6.1 INFO: rcu detected stall in br_forward_delay_timer_expired 1 233d 233d 0/3 auto-obsoleted due to no activity on 2025/01/08 10:41

Sample crash report:
hrtimer: interrupt took 24577 ns
rcu: INFO: rcu_preempt self-detected stall on CPU
rcu: 	0-....: (10500 ticks this GP) idle=a5a/1/0x4000000000000004 softirq=6931/6936 fqs=5222 
	(t=10500 jiffies g=4921 q=1910)
NMI backtrace for cpu 0
CPU: 0 PID: 7959 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:1514 [inline]
 __hrtimer_run_queues+0x364/0xe40 kernel/time/hrtimer.c:1576
 hrtimer_interrupt+0x314/0x770 kernel/time/hrtimer.c:1638
 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:arch_local_irq_restore arch/x86/include/asm/paravirt.h:752 [inline]
RIP: 0010:kfree+0x239/0x2c0 mm/slab.c:3757
Code: 50 7e 0f 85 20 fe ff ff e8 d5 a5 4e ff e9 16 fe ff ff e8 3a a6 c8 ff 48 83 3d 8a 72 61 07 00 0f 84 85 00 00 00 48 89 df 57 9d <0f> 1f 44 00 00 5b 41 5c 41 5d 41 5e 5d c3 e8 14 a6 c8 ff 48 83 3d
RSP: 0018:ffff88802d209a40 EFLAGS: 00000282 ORIG_RAX: ffffffffffffff13
RAX: 0000000000000007 RBX: 0000000000000282 RCX: 0000000000000002
RDX: 0000000000000000 RSI: ffff888018854a38 RDI: 0000000000000282
RBP: ffff88802d209a60 R08: 1ffffffff15377b5 R09: fffffbfff15377b6
R10: fffffbfff15377b5 R11: ffffffff8a9bbdaf R12: ffff88802aede000
R13: ffff88802cc00c40 R14: ffffffff85c6a5a3 R15: ffff8880246e3000
 skb_free_head+0x93/0xb0 net/core/skbuff.c:591
 skb_release_data+0x551/0x8d0 net/core/skbuff.c:611
 skb_release_all+0x4d/0x60 net/core/skbuff.c:665
 __kfree_skb net/core/skbuff.c:679 [inline]
 consume_skb net/core/skbuff.c:838 [inline]
 consume_skb+0xfb/0x410 net/core/skbuff.c:832
 netlink_broadcast_filtered+0x34e/0xd20 net/netlink/af_netlink.c:1512
 netlink_broadcast net/netlink/af_netlink.c:1534 [inline]
 nlmsg_multicast include/net/netlink.h:968 [inline]
 nlmsg_notify+0x93/0x250 net/netlink/af_netlink.c:2520
 rtnl_notify+0xc5/0xf0 net/core/rtnetlink.c:737
 br_ifinfo_notify+0x102/0x1d0 net/bridge/br_netlink.c:501
 br_forward_delay_timer_expired+0x11e/0x410 net/bridge/br_stp_timer.c:98
 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 2e 81 a9 07 00 0f 84 e0 00 00 00 e8 eb 2a 0b 00 48 89 df 57 9d <0f> 1f 44 00 00 45 31 ed e9 39 fe ff ff e8 d4 2a 0b 00 0f 0b e9 23
RSP: 0018:ffff88801885fa80 EFLAGS: 00000216 ORIG_RAX: ffffffffffffff13
RAX: 0000000000040000 RBX: 0000000000000216 RCX: ffffc900062ad000
RDX: 0000000000008567 RSI: ffffffff8169b335 RDI: 0000000000000216
RBP: ffff88801885fab0 R08: 1ffffffff15377ba R09: fffffbfff15377bb
R10: fffffbfff15377ba R11: ffffffff8a9bbdd7 R12: 0000000000000200
R13: ffff88801885fb00 R14: ffff88801885fbd0 R15: ffffffff818bd170
 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]
 __x64_sys_perf_event_open+0xbe/0x150 kernel/events/core.c:11151
 do_syscall_64+0xfa/0x790 arch/x86/entry/common.c:294
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x45a759
Code: bd b1 fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 0f 83 8b b1 fb ff c3 66 2e 0f 1f 84 00 00 00 00
RSP: 002b:00007f076c852c88 EFLAGS: 00000246 ORIG_RAX: 000000000000012a
RAX: ffffffffffffffda RBX: 000000000071bf00 RCX: 000000000045a759
RDX: ffffffffffffffff RSI: 0000000000000000 RDI: 000000002001d000
RBP: 0000000000000005 R08: 0000000000000000 R09: 0000000000000000
R10: ffffffffffffffff R11: 0000000000000246 R12: 00007f076c8536d4
R13: 00000000004aec17 R14: 00000000006f1cb0 R15: 00000000ffffffff

Crashes (2):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2019/11/29 12:20 upstream 81b6b96475ac d29b9e84 .config console log report ci-qemu-upstream
2019/11/29 10:30 upstream 81b6b96475ac 4f7e1d0f .config console log report ci-qemu-upstream
* Struck through repros no longer work on HEAD.