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BUG: soft lockup in br_multicast_group_expired

Status: auto-obsoleted due to no activity on 2025/08/06 07:32
First crash: 151d, last: 112d
Similar bugs (4)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
android-6-1 BUG: soft lockup in br_multicast_group_expired 1 1 374d 374d 0/2 auto-obsoleted due to no activity on 2024/11/17 00:46
android-5-10 BUG: soft lockup in br_multicast_group_expired (2) 1 1 265d 265d 0/2 auto-obsoleted due to no activity on 2025/03/05 23:26
upstream BUG: soft lockup in br_multicast_group_expired net 1 1 2098d 2098d 0/29 closed as invalid on 2019/11/30 16:54
android-5-10 BUG: soft lockup in br_multicast_group_expired 1 1 386d 386d 0/2 auto-obsoleted due to no activity on 2024/11/05 04:11

Sample crash report:
watchdog: BUG: soft lockup - CPU#1 stuck for 123s! [syz.0.32:463]
Modules linked in:
CPU: 1 PID: 463 Comm: syz.0.32 Not tainted 5.4.292-syzkaller-00021-gcd8e74fa0fa3 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025
RIP: 0010:slab_alloc_node mm/slub.c:2768 [inline]
RIP: 0010:slab_alloc mm/slub.c:2837 [inline]
RIP: 0010:__kmalloc_track_caller+0x84/0x2d0 mm/slub.c:4449
Code: 31 c0 e9 c9 00 00 00 4c 89 65 d0 0f 1f 44 00 00 4d 89 ec 4d 85 e4 0f 84 ae 00 00 00 e9 9c 01 00 00 49 8b 04 24 65 48 8b 50 08 <49> 8b 04 24 65 48 03 05 d0 2f 75 7e 48 3b 50 08 75 e5 4c 8b 38 4d
RSP: 0018:ffff8881f6f09a08 EFLAGS: 00000286 ORIG_RAX: ffffffffffffff13
RAX: 000000000005b120 RBX: 0000000000082a20 RCX: 0000000000000000
RDX: 00000000000440a1 RSI: 0000000000000000 RDI: 0000000000000000
RBP: ffff8881f6f09a48 R08: 00000000e5a7e800 R09: 0000000001a479e3
R10: 0000000033b46f0b R11: 00000000eaaf9291 R12: ffff8881f5c02500
R13: ffff8881f5c02500 R14: 0000000000082a20 R15: ffffffff83cb1074
FS:  00007faca3f376c0(0000) GS:ffff8881f6f00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007faca579e733 CR3: 00000001c76b5000 CR4: 00000000003406a0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000090602
Call Trace:
 <IRQ>
 __kmalloc_reserve net/core/skbuff.c:142 [inline]
 __alloc_skb+0xdc/0x500 net/core/skbuff.c:210
 alloc_skb include/linux/skbuff.h:1080 [inline]
 nlmsg_new include/net/netlink.h:888 [inline]
 __br_mdb_notify+0x424/0xbd0 net/bridge/br_mdb.c:424
 br_mdb_notify+0x17e/0x220 net/bridge/br_mdb.c:457
 br_multicast_host_leave net/bridge/br_multicast.c:532 [inline]
 br_multicast_group_expired+0x192/0x350 net/bridge/br_multicast.c:151
 call_timer_fn+0x3c/0x380 kernel/time/timer.c:1448
 expire_timers kernel/time/timer.c:1493 [inline]
 __run_timers+0x81d/0xb60 kernel/time/timer.c:1817
 run_timer_softirq+0x6a/0xf0 kernel/time/timer.c:1830
 __do_softirq+0x236/0x660 kernel/softirq.c:292
 invoke_softirq kernel/softirq.c:373 [inline]
 irq_exit+0x197/0x1c0 kernel/softirq.c:413
 exiting_irq arch/x86/include/asm/apic.h:539 [inline]
 smp_apic_timer_interrupt+0x11d/0x490 arch/x86/kernel/apic/apic.c:1161
 apic_timer_interrupt+0xf/0x20 arch/x86/entry/entry_64.S:834
 </IRQ>
RIP: 0010:__raw_spin_unlock_irq include/linux/spinlock_api_smp.h:169 [inline]
RIP: 0010:_raw_spin_unlock_irq+0x49/0x70 kernel/locking/spinlock.c:199
Code: 12 48 89 fb 48 c7 c7 b0 2d cb 85 e8 31 7f 62 fd 48 89 df 48 83 3d c6 33 a0 01 00 74 27 e8 93 37 1d fd 66 90 fb bf 01 00 00 00 <e8> 72 7a 16 fd 65 8b 05 87 93 d7 7b 85 c0 74 03 5b 5d c3 e8 7f 4d
RSP: 0018:ffff8881e783f1e8 EFLAGS: 00000246 ORIG_RAX: ffffffffffffff13
RAX: 0000000000000001 RBX: ffff8881e7c68078 RCX: dffffc0000000000
RDX: 0000000000000001 RSI: 0000000000000008 RDI: 0000000000000001
RBP: ffff8881e783f1f0 R08: dffffc0000000000 R09: ffffed103cf8d001
R10: ffffed103cf8d001 R11: 1ffff1103cf8d000 R12: ffff8881f6f57b40
R13: dffffc0000000000 R14: ffff8881e7c68000 R15: ffff8881e7c68000
 rq_unlock_irq kernel/sched/sched.h:1270 [inline]
 __schedule+0xc6f/0x12a0 kernel/sched/core.c:4312
 preempt_schedule_irq+0x9b/0x110 kernel/sched/core.c:4560
 retint_kernel+0x1b/0x1b
RIP: 0010:memset_erms+0xb/0x10 arch/x86/lib/memset_64.S:65
Code: 03 40 0f b6 f6 48 b8 01 01 01 01 01 01 01 01 48 0f af c6 f3 48 ab 89 d1 f3 aa 4c 89 c8 c3 90 49 89 f9 40 88 f0 48 89 d1 f3 aa <4c> 89 c8 c3 90 49 89 fa 40 0f b6 ce 48 b8 01 01 01 01 01 01 01 01
RSP: 0018:ffff8881e783f440 EFLAGS: 00000256 ORIG_RAX: ffffffffffffff02
RAX: ffff8881e7c68000 RBX: 0000000000000060 RCX: 0000000000000000
RDX: 0000000000000060 RSI: 0000000000000000 RDI: ffff8881e783f548
RBP: ffff8881e783f460 R08: dffffc0000000000 R09: ffff8881e783f4e8
R10: ffffed103cf07ea9 R11: 1ffff1103cf07e9d R12: 0000000000000000
R13: 1ffff1103cf07eb0 R14: 0000000000000000 R15: ffff8881e783f4e8
 __unwind_start+0x34/0x3a0 arch/x86/kernel/unwind_frame.c:371
 unwind_start arch/x86/include/asm/unwind.h:60 [inline]
 arch_stack_walk+0xd8/0x140 arch/x86/kernel/stacktrace.c:24
 stack_trace_save+0xaa/0xf0 kernel/stacktrace.c:123
 save_stack+0x97/0x560 mm/page_owner.c:122
 __reset_page_owner+0x23/0x110 mm/page_owner.c:149
 reset_page_owner include/linux/page_owner.h:24 [inline]
 free_pages_prepare mm/page_alloc.c:1176 [inline]
 free_pcp_prepare mm/page_alloc.c:1233 [inline]
 free_unref_page_prepare+0x2a9/0x3a0 mm/page_alloc.c:3085
 free_unref_page mm/page_alloc.c:3134 [inline]
 free_the_page mm/page_alloc.c:4954 [inline]
 __free_pages+0xaa/0x110 mm/page_alloc.c:4962
 __vunmap+0x76a/0x8a0 mm/vmalloc.c:2260
 __vfree mm/vmalloc.c:2308 [inline]
 vfree+0x61/0x90 mm/vmalloc.c:2338
 kcov_put kernel/kcov.c:396 [inline]
 kcov_close+0x2b/0x50 kernel/kcov.c:495
 __fput+0x2a3/0x730 fs/file_table.c:281
 ____fput+0x15/0x20 fs/file_table.c:314
 task_work_run+0x146/0x170 kernel/task_work.c:113
 exit_task_work include/linux/task_work.h:22 [inline]
 do_exit+0xa43/0x2660 kernel/exit.c:861
 do_group_exit+0x13e/0x300 kernel/exit.c:984
 get_signal+0xdee/0x13d0 kernel/signal.c:2738
 do_signal+0xad/0xda0 arch/x86/kernel/signal.c:809
 exit_to_usermode_loop+0xc4/0x1b0 arch/x86/entry/common.c:159
 prepare_exit_to_usermode+0x18e/0x1f0 arch/x86/entry/common.c:194
 ret_from_intr+0x1c/0x1c
RIP: 0033:0x7faca579e75d
Code: Bad RIP value.
RSP: 002b:00007faca3f37060 EFLAGS: 00010202
RAX: 0000000000000009 RBX: 00007faca5af5fa0 RCX: 00007faca5950ab1
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000200000000040
RBP: 00007faca5950ab1 R08: 0000000000000000 R09: 0000000000000000
R10: ffffffffffffffff R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007faca5af5fa0 R15: 00007ffd64ba8e08
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 PID: 768 Comm: kworker/u4:4 Not tainted 5.4.292-syzkaller-00021-gcd8e74fa0fa3 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025
Workqueue: events_unbound toggle_allocation_gate
RIP: 0010:csd_lock_wait kernel/smp.c:109 [inline]
RIP: 0010:smp_call_function_single+0x1da/0x410 kernel/smp.c:311
Code: 5c 02 00 00 89 c3 44 8b 74 24 58 44 89 f6 83 e6 01 31 ff e8 b8 51 0a 00 41 83 e6 01 75 0a e8 5d 4e 0a 00 e9 a6 00 00 00 f3 90 <f7> 44 24 58 01 00 00 00 0f 84 91 00 00 00 e8 43 4e 0a 00 eb e9 e8
RSP: 0018:ffff8881e86877e0 EFLAGS: 00000293
RAX: ffffffff8155309d RBX: 0000000000000000 RCX: ffff8881ddde9f80
RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000000
RBP: ffff8881e86878d0 R08: dffffc0000000000 R09: ffffed103edeb189
R10: ffffed103edeb189 R11: 1ffff1103edeb188 R12: ffff8881e8687820
R13: 0000000000000001 R14: 0000000000000001 R15: 1ffff1103d0d0f00
FS:  0000000000000000(0000) GS:ffff8881f6e00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007faca579e733 CR3: 0000000005c0e000 CR4: 00000000003406b0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000600
Call Trace:
 smp_call_function_many+0x6d6/0x990 kernel/smp.c:451
 smp_call_function kernel/smp.c:509 [inline]
 on_each_cpu+0xa8/0x170 kernel/smp.c:616
 text_poke_bp_batch+0xf7/0x260 arch/x86/kernel/alternative.c:1051
 arch_jump_label_transform_apply+0x2b/0x50 arch/x86/kernel/jump_label.c:167
 __jump_label_update+0x37c/0x3a0 kernel/jump_label.c:449
 jump_label_update+0x34c/0x3e0 kernel/jump_label.c:808
 static_key_disable_cpuslocked+0xc5/0x1a0 kernel/jump_label.c:207
 static_key_disable+0x1a/0x30 kernel/jump_label.c:215
 toggle_allocation_gate+0x196/0x230 mm/kfence/core.c:638
 process_one_work+0x73b/0xcc0 kernel/workqueue.c:2290
 worker_thread+0xa5c/0x13b0 kernel/workqueue.c:2436
 kthread+0x31e/0x3a0 kernel/kthread.c:288
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:354

Crashes (2):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2025/05/08 07:32 android12-5.4 cd8e74fa0fa3 dbf35fa1 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-5-4-perf-kasan BUG: soft lockup in br_multicast_group_expired
2025/03/29 16:30 android12-5.4 41adfeb3d639 cf25e2c2 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-5-4-perf-kasan BUG: soft lockup in br_multicast_group_expired
* Struck through repros no longer work on HEAD.