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BUG: soft lockup in br_forward_delay_timer_expired

Status: auto-obsoleted due to no activity on 2025/03/26 03:08
Reported-by: syzbot+2f32aee9fba8452809d4@syzkaller.appspotmail.com
First crash: 105d, last: 105d
▶ ▼ Similar bugs (4)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
linux-4.14 BUG: soft lockup in br_forward_delay_timer_expired 1 1153d 1153d 0/1 auto-closed as invalid on 2022/06/13 01:08
upstream BUG: soft lockup in br_forward_delay_timer_expired bridge 1 1958d 1958d 0/28 closed as invalid on 2019/11/30 16:54
linux-6.1 INFO: rcu detected stall in br_forward_delay_timer_expired (2) 1 41d 41d 0/3 upstream: reported on 2025/02/28 07:03
linux-6.1 INFO: rcu detected stall in br_forward_delay_timer_expired 1 192d 192d 0/3 auto-obsoleted due to no activity on 2025/01/08 10:41

Sample crash report:
watchdog: BUG: soft lockup - CPU#1 stuck for 143s! [syz.5.373:3467]
Modules linked in:
CPU: 1 PID: 3467 Comm: syz.5.373 Not tainted 5.15.173-syzkaller-00161-gb4bd207b0380 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024
RIP: 0010:longest_prefix_match+0x34/0x650 kernel/bpf/lpm_trie.c:168
Code: 41 54 53 48 83 ec 40 49 89 d7 48 89 f3 49 89 fe 49 bc 00 00 00 00 00 fc ff df e8 b7 7d e5 ff 4c 89 e2 48 89 5d c0 48 83 c3 20 <48> 89 d8 48 c1 e8 03 42 0f b6 04 20 84 c0 0f 85 83 04 00 00 8b 1b
RSP: 0018:ffffc900001d0830 EFLAGS: 00000286
RAX: ffffffff818ae8f9 RBX: ffff88810ee374a0 RCX: ffff88811e474f00
RDX: dffffc0000000000 RSI: ffff88810ee37480 RDI: ffff888112161400
RBP: ffffc900001d0898 R08: ffffffff818ad2aa R09: 0000000000000016
R10: ffffc900001d06b0 R11: dffffc0000000001 R12: dffffc0000000000
R13: ffff88810ee37480 R14: ffff888112161400 R15: ffffc900001d0908
FS:  00007fe7741806c0(0000) GS:ffff8881f7100000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fe773d3cd58 CR3: 0000000138674000 CR4: 00000000003506a0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000600
Call Trace:
 <IRQ>
 trie_lookup_elem+0xd5/0x2b0 kernel/bpf/lpm_trie.c:247
 bpf_prog_c265141a911eaec5+0x3d/0x924
 bpf_dispatcher_nop_func include/linux/bpf.h:785 [inline]
 __bpf_prog_run include/linux/filter.h:628 [inline]
 bpf_prog_run include/linux/filter.h:635 [inline]
 __bpf_trace_run kernel/trace/bpf_trace.c:1878 [inline]
 bpf_trace_run3+0x11e/0x250 kernel/trace/bpf_trace.c:1916
 __bpf_trace_kmem_cache_free+0x99/0xc0 include/trace/events/kmem.h:138
 trace_kmem_cache_free include/trace/events/kmem.h:138 [inline]
 kmem_cache_free+0x30e/0x330 mm/slub.c:3540
 kfree_skbmem+0x104/0x170
 __kfree_skb net/core/skbuff.c:758 [inline]
 consume_skb+0xb4/0x250 net/core/skbuff.c:930
 netlink_broadcast_filtered+0x10f4/0x1220 net/netlink/af_netlink.c:1540
 netlink_broadcast net/netlink/af_netlink.c:1562 [inline]
 nlmsg_multicast include/net/netlink.h:1033 [inline]
 nlmsg_notify+0x101/0x1c0 net/netlink/af_netlink.c:2551
 rtnl_notify+0x9c/0xd0 net/core/rtnetlink.c:759
 br_info_notify+0x10c/0x170 net/bridge/br_netlink.c:610
 br_ifinfo_notify+0x28/0x30 net/bridge/br_netlink.c:622
 br_forward_delay_timer_expired+0x232/0x270 net/bridge/br_stp_timer.c:98
 call_timer_fn+0x3b/0x2d0 kernel/time/timer.c:1457
 expire_timers kernel/time/timer.c:1502 [inline]
 __run_timers+0x72a/0xa10 kernel/time/timer.c:1773
 run_timer_softirq+0x69/0xf0 kernel/time/timer.c:1786
 handle_softirqs+0x25e/0x5c0 kernel/softirq.c:565
 __do_softirq kernel/softirq.c:603 [inline]
 invoke_softirq kernel/softirq.c:425 [inline]
 __irq_exit_rcu+0x52/0xf0 kernel/softirq.c:652
 irq_exit_rcu+0x9/0x10 kernel/softirq.c:664
 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1108 [inline]
 sysvec_apic_timer_interrupt+0xa9/0xc0 arch/x86/kernel/apic/apic.c:1108
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x1b/0x20 arch/x86/include/asm/idtentry.h:676
RIP: 0010:finish_task_switch+0x16f/0x7b0 kernel/sched/core.c:5024
Code: 74 08 4c 89 ff e8 b1 73 65 00 49 8b 1f 48 85 db 4c 8b 6d c0 0f 85 ce 00 00 00 4c 89 e7 e8 39 56 9a 03 fb 49 8d 9d 38 0b 00 00 <48> 89 d8 48 c1 e8 03 49 be 00 00 00 00 00 fc ff df 42 0f b6 04 30
RSP: 0018:ffffc90000a775e0 EFLAGS: 00000282
RAX: 0000000080000001 RBX: ffff88811e475a38 RCX: 0000000000000002
RDX: 0000000040000002 RSI: 0000000000000000 RDI: 0000000000000001
RBP: ffffc90000a77630 R08: ffffffff81920849 R09: fffffbfff0e53503
R10: 0000000000000000 R11: dffffc0000000001 R12: ffff8881f71378c0
R13: ffff88811e474f00 R14: 1ffff1103ee27081 R15: ffff8881f7138408
 context_switch kernel/sched/core.c:5155 [inline]
 __schedule+0xcd4/0x1590 kernel/sched/core.c:6512
 preempt_schedule_irq+0xc7/0x140 kernel/sched/core.c:6916
 irqentry_exit_cond_resched+0x2a/0x30 kernel/entry/common.c:398
 irqentry_exit+0x30/0x40 kernel/entry/common.c:432
 sysvec_apic_timer_interrupt+0x64/0xc0 arch/x86/kernel/apic/apic.c:1108
 asm_sysvec_apic_timer_interrupt+0x1b/0x20 arch/x86/include/asm/idtentry.h:676
RIP: 0010:user_mode arch/x86/include/asm/ptrace.h:136 [inline]
RIP: 0010:kernelmode_fixup_or_oops+0x40/0xd0 arch/x86/mm/fault.c:716
Code: ed 3a 00 49 8d 9c 24 88 00 00 00 48 89 d8 48 c1 e8 03 48 b9 00 00 00 00 00 fc ff df 80 3c 08 00 74 08 48 89 df e8 60 45 7d 00 <48> 8b 1b 48 89 de 48 83 e6 03 31 ff e8 5f f1 3a 00 48 83 e3 03 75
RSP: 0018:ffffc90000a778c0 EFLAGS: 00000246
RAX: 1ffff9200014ef70 RBX: ffffc90000a77b80 RCX: dffffc0000000000
RDX: ffffc90009c6f000 RSI: 0000000000000038 RDI: 0000000000000039
RBP: ffffc90000a778e0 R08: ffffffff81357530 R09: ffffed10212fec00
R10: 0000000000000000 R11: dffffc0000000001 R12: ffffc90000a77af8
R13: ffffc90000a77b80 R14: 0000000000000000 R15: 0000000000000000
 __bad_area_nosemaphore+0xc2/0x480 arch/x86/mm/fault.c:766
 __bad_area arch/x86/mm/fault.c:829 [inline]
 bad_area+0x73/0x90 arch/x86/mm/fault.c:835
 handle_page_fault arch/x86/mm/fault.c:1509 [inline]
 exc_page_fault+0x57c/0x7f0 arch/x86/mm/fault.c:1565
 asm_exc_page_fault+0x27/0x30 arch/x86/include/asm/idtentry.h:606
RIP: 0010:copy_user_generic_unrolled+0x86/0xc0 arch/x86/lib/copy_user_64.S:91
Code: 4c 8b 5e 38 4c 89 47 20 4c 89 4f 28 4c 89 57 30 4c 89 5f 38 48 8d 76 40 48 8d 7f 40 ff c9 75 b6 89 d1 83 e2 07 c1 e9 03 74 12 <4c> 8b 06 4c 89 07 48 8d 76 08 48 8d 7f 08 ff c9 75 ee 21 d2 74 10
RSP: 0018:ffffc90000a77ba0 EFLAGS: 00050202
RAX: ffffffff82660001 RBX: 0000000000000008 RCX: 0000000000000001
RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffffc90000a77d50
RBP: ffffc90000a77bd0 R08: dffffc0000000000 R09: fffff5200014efab
R10: 0000000000000000 R11: dffffc0000000001 R12: 0000000000000008
R13: 00007ffffffff000 R14: ffffc90000a77d50 R15: 0000000000000000
 copy_from_user include/linux/uaccess.h:192 [inline]
 _perf_ioctl kernel/events/core.c:5778 [inline]
 perf_ioctl+0x660/0x2100 kernel/events/core.c:5882
 vfs_ioctl fs/ioctl.c:51 [inline]
 __do_sys_ioctl fs/ioctl.c:874 [inline]
 __se_sys_ioctl+0x114/0x190 fs/ioctl.c:860
 __x64_sys_ioctl+0x7b/0x90 fs/ioctl.c:860
 x64_sys_call+0x98/0x9a0 arch/x86/include/generated/asm/syscalls_64.h:17
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7fe775b2fd29
Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 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 73 01 c3 48 c7 c1 a8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007fe774180038 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00007fe775d20080 RCX: 00007fe775b2fd29
RDX: 0000000000000000 RSI: 0000000040082404 RDI: 0000000000000008
RBP: 00007fe775babaa8 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007fe775d20080 R15: 00007ffc032e2318
 </TASK>
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 PID: 2657 Comm: syz.7.309 Not tainted 5.15.173-syzkaller-00161-gb4bd207b0380 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024
RIP: 0010:__sanitizer_cov_trace_pc+0x1/0x60 kernel/kcov.c:199
Code: 00 00 0f 0b 0f 1f 44 00 00 55 48 89 e5 53 48 89 fb e8 13 00 00 00 48 8b 3d e4 3b b9 05 48 89 de e8 84 93 41 00 5b 5d c3 cc 55 <48> 89 e5 48 8b 45 08 65 48 8b 0d c0 06 92 7e 65 8b 15 c1 06 92 7e
RSP: 0018:ffffc90000007100 EFLAGS: 00000082
RAX: 1ffff1103ee05347 RBX: ffff8881f7029a00 RCX: 7fffffffffffffff
RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffff8881f7029a00
RBP: ffffc90000007168 R08: ffffffff8160ee89 R09: ffff88811596d838
R10: 0000000000000000 R11: dffffc0000000001 R12: 0000000000000000
R13: 0000000000000002 R14: ffff8881f7029a30 R15: 7fffffffffffffff
FS:  0000000000000000(0000) GS:ffff8881f7000000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fe773d3bf98 CR3: 000000010c473000 CR4: 00000000003506b0
DR0: 0100000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000600
Call Trace:
 <NMI>
 </NMI>
 <IRQ>
 __hrtimer_get_next_event kernel/time/hrtimer.c:578 [inline]
 hrtimer_update_next_event kernel/time/hrtimer.c:604 [inline]
 hrtimer_interrupt+0x4b3/0xaa0 kernel/time/hrtimer.c:1816
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1097 [inline]
 __sysvec_apic_timer_interrupt+0xfb/0x3f0 arch/x86/kernel/apic/apic.c:1114
 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1108 [inline]
 sysvec_apic_timer_interrupt+0x53/0xc0 arch/x86/kernel/apic/apic.c:1108
 asm_sysvec_apic_timer_interrupt+0x1b/0x20 arch/x86/include/asm/idtentry.h:676
RIP: 0010:get_current arch/x86/include/asm/current.h:15 [inline]
RIP: 0010:update_stack_state+0x399/0x460 arch/x86/kernel/unwind_frame.c:242
Code: 00 00 00 48 83 c0 08 48 89 c3 eb 08 48 8b 5d 88 48 83 eb 80 4c 89 f0 48 c1 e8 03 42 80 3c 38 00 74 08 4c 89 f7 e8 e7 a5 7d 00 <65> 48 8b 05 7f 54 cd 7e 49 39 06 74 0d 48 89 df e8 42 fc ff ff 49
RSP: 0018:ffffc90000007390 EFLAGS: 00000246
RAX: 1ffff92000000ea1 RBX: ffffc90000f4fed8 RCX: 1ffff92000000ea7
RDX: 1ffff92000000e9e RSI: ffffc90000f4fed0 RDI: ffffc90000007538
RBP: ffffc90000007448 R08: ffffc900000075c8 R09: 0000000000000023
R10: ffffc900000075d0 R11: dffffc0000000001 R12: 1ffff92000000ea4
R13: 0000000000000000 R14: ffffc90000007508 R15: dffffc0000000000
 unwind_next_frame+0x3cb/0x700 arch/x86/kernel/unwind_frame.c:305
 arch_stack_walk+0x10d/0x140 arch/x86/kernel/stacktrace.c:25
 stack_trace_save+0x113/0x1c0 kernel/stacktrace.c:122
 kasan_save_stack mm/kasan/common.c:38 [inline]
 kasan_set_track mm/kasan/common.c:45 [inline]
 set_alloc_info mm/kasan/common.c:433 [inline]
 __kasan_slab_alloc+0xb1/0xe0 mm/kasan/common.c:466
 kasan_slab_alloc include/linux/kasan.h:217 [inline]
 slab_post_alloc_hook+0x53/0x2c0 mm/slab.h:550
 slab_alloc_node mm/slub.c:3240 [inline]
 slab_alloc mm/slub.c:3250 [inline]
 kmem_cache_alloc+0xf5/0x250 mm/slub.c:3255
 dst_alloc+0x164/0x1e0 net/core/dst.c:92
 ip6_dst_alloc net/ipv6/route.c:342 [inline]
 icmp6_dst_alloc+0xfc/0x560 net/ipv6/route.c:3275
 ndisc_send_skb+0x27f/0xc90 net/ipv6/ndisc.c:491
 ndisc_send_rs+0x532/0x6a0 net/ipv6/ndisc.c:705
 addrconf_rs_timer+0x2d1/0x600 net/ipv6/addrconf.c:3979
 call_timer_fn+0x3b/0x2d0 kernel/time/timer.c:1457
 expire_timers kernel/time/timer.c:1502 [inline]
 __run_timers+0x72a/0xa10 kernel/time/timer.c:1773
 run_timer_softirq+0x69/0xf0 kernel/time/timer.c:1786
 handle_softirqs+0x25e/0x5c0 kernel/softirq.c:565
 __do_softirq kernel/softirq.c:603 [inline]
 invoke_softirq kernel/softirq.c:425 [inline]
 __irq_exit_rcu+0x52/0xf0 kernel/softirq.c:652
 irq_exit_rcu+0x9/0x10 kernel/softirq.c:664
 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1108 [inline]
 sysvec_apic_timer_interrupt+0xa9/0xc0 arch/x86/kernel/apic/apic.c:1108
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x1b/0x20 arch/x86/include/asm/idtentry.h:676
RIP: 0010:finish_task_switch+0x16f/0x7b0 kernel/sched/core.c:5024
Code: 74 08 4c 89 ff e8 b1 73 65 00 49 8b 1f 48 85 db 4c 8b 6d c0 0f 85 ce 00 00 00 4c 89 e7 e8 39 56 9a 03 fb 49 8d 9d 38 0b 00 00 <48> 89 d8 48 c1 e8 03 49 be 00 00 00 00 00 fc ff df 42 0f b6 04 30
RSP: 0018:ffffc90000f4f100 EFLAGS: 00000282
RAX: 0000000080000001 RBX: ffff888121774678 RCX: 0000000000000002
RDX: 0000000040000000 RSI: 0000000000000000 RDI: 0000000000000001
RBP: ffffc90000f4f150 R08: ffffffff81920849 R09: fffffbfff0e53503
R10: 0000000000000000 R11: dffffc0000000001 R12: ffff8881f70378c0
R13: ffff888121773b40 R14: 1ffff1103ee07081 R15: ffff8881f7038408
 context_switch kernel/sched/core.c:5155 [inline]
 __schedule+0xcd4/0x1590 kernel/sched/core.c:6512
 preempt_schedule_irq+0xc7/0x140 kernel/sched/core.c:6916
 irqentry_exit_cond_resched+0x2a/0x30 kernel/entry/common.c:398
 irqentry_exit+0x30/0x40 kernel/entry/common.c:432
 sysvec_apic_timer_interrupt+0x64/0xc0 arch/x86/kernel/apic/apic.c:1108
 asm_sysvec_apic_timer_interrupt+0x1b/0x20 arch/x86/include/asm/idtentry.h:676
RIP: 0010:__sanitizer_cov_trace_const_cmp8+0x1/0x80 kernel/kcov.c:299
Code: 05 00 00 00 48 89 44 0a 10 48 89 74 0a 18 4c 89 44 0a 20 49 ff c1 4c 89 09 5d c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 55 <48> 89 e5 4c 8b 45 08 65 48 8b 0d 80 02 92 7e 65 8b 05 81 02 92 7e
RSP: 0018:ffffc90000f4f3f0 EFLAGS: 00000246
RAX: 1ffffd400096b3e9 RBX: 0000000000000000 RCX: ffff888121773b40
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: ffffc90000f4f430 R08: ffffffff81afe5fc R09: fffff9400096b3e1
R10: 0000000000000000 R11: dffffc0000000001 R12: ffffea0004b59f40
R13: ffffea0004b59f48 R14: dffffc0000000000 R15: 1ffffd400096b3e9
 free_pages_and_swap_cache+0x63/0xa0 mm/swap_state.c:319
 tlb_batch_pages_flush mm/mmu_gather.c:49 [inline]
 tlb_flush_mmu_free mm/mmu_gather.c:240 [inline]
 tlb_flush_mmu+0xd0/0x180 mm/mmu_gather.c:247
 zap_pte_range mm/memory.c:1525 [inline]
 zap_pmd_range mm/memory.c:1574 [inline]
 zap_pud_range mm/memory.c:1603 [inline]
 zap_p4d_range mm/memory.c:1624 [inline]
 unmap_page_range+0x1c70/0x1ed0 mm/memory.c:1645
 unmap_single_vma mm/memory.c:1690 [inline]
 unmap_vmas+0x389/0x560 mm/memory.c:1722
 exit_mmap+0x3e4/0x940 mm/mmap.c:3215
 __mmput+0x95/0x310 kernel/fork.c:1180
 mmput+0x5b/0x170 kernel/fork.c:1203
 exit_mm kernel/exit.c:554 [inline]
 do_exit+0xb9c/0x2ca0 kernel/exit.c:867
 do_group_exit+0x141/0x310 kernel/exit.c:1002
 get_signal+0x7a3/0x1630 kernel/signal.c:2907
 arch_do_signal_or_restart+0xbd/0x1680 arch/x86/kernel/signal.c:867
 handle_signal_work kernel/entry/common.c:154 [inline]
 exit_to_user_mode_loop+0xa0/0xe0 kernel/entry/common.c:178
 exit_to_user_mode_prepare+0x5a/0xa0 kernel/entry/common.c:214
 __syscall_exit_to_user_mode_work kernel/entry/common.c:296 [inline]
 syscall_exit_to_user_mode+0x26/0x160 kernel/entry/common.c:307
 do_syscall_64+0x47/0xb0 arch/x86/entry/common.c:86
 entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7f61ad97fd29
Code: Unable to access opcode bytes at RIP 0x7f61ad97fcff.
RSP: 002b:00007f61abff10e8 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca
RAX: 0000000000000001 RBX: 00007f61adb6ffa8 RCX: 00007f61ad97fd29
RDX: 00000000000f4240 RSI: 0000000000000081 RDI: 00007f61adb6ffac
RBP: 00007f61adb6ffa0 R08: 00007ffcab7930b0 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00007f61adb6ffac
R13: 0000000000000000 R14: 00007ffcab630380 R15: 00007ffcab630468
 </TASK>

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2024/12/26 03:04 android13-5.15-lts b4bd207b0380 444551c4 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-5-15-perf BUG: soft lockup in br_forward_delay_timer_expired
* Struck through repros no longer work on HEAD.