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BUG: soft lockup in br_multicast_port_group_expired (2)

Status: auto-obsoleted due to no activity on 2025/07/26 14:48
First crash: 163d, last: 123d
▶ ▼ Similar bugs (5)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
android-5-15 BUG: soft lockup in br_multicast_port_group_expired 1 2 295d 377d 0/2 auto-obsoleted due to no activity on 2025/02/05 03:41
android-6-1 BUG: soft lockup in br_multicast_port_group_expired 1 3 328d 440d 0/2 auto-obsoleted due to no activity on 2025/01/02 19:42
android-54 BUG: soft lockup in br_multicast_port_group_expired 1 1 450d 450d 0/2 auto-obsoleted due to no activity on 2024/09/03 00:58
android-5-10 BUG: soft lockup in br_multicast_port_group_expired 1 1 370d 370d 0/2 auto-obsoleted due to no activity on 2024/11/21 20:11
linux-5.15 INFO: rcu detected stall in br_multicast_port_group_expired 1 1 421d 421d 0/3 auto-obsoleted due to no activity on 2024/10/11 20:34

Sample crash report:
watchdog: BUG: soft lockup - CPU#0 stuck for 123s! [syz.6.116:798]
Modules linked in:
CPU: 0 PID: 798 Comm: syz.6.116 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:set_track mm/kasan/common.c:77 [inline]
RIP: 0010:__kasan_kmalloc+0x138/0x200 mm/kasan/common.c:529
Code: 02 48 8b 44 24 18 f6 40 0b 08 44 8b 74 24 0c 0f 84 a5 00 00 00 4c 63 a8 c0 01 00 00 65 48 8b 05 4e 2f 75 7e 8b 80 50 05 00 00 <42> 89 04 2b 4c 8d 64 24 20 45 31 ff ba 00 02 00 00 4c 89 e7 31 f6
RSP: 0018:ffff8881f6e09740 EFLAGS: 00000202 ORIG_RAX: ffffffffffffff13
RAX: 000000000000031e RBX: ffff8881db0eb400 RCX: 0000000000000000
RDX: 0000000000000000 RSI: 00000000000000fc RDI: ffffed103b61d6c0
RBP: ffff8881f6e099a0 R08: 0000000000000004 R09: ffffed103b61d6c0
R10: ffffed103edc12fc R11: 1ffff1103edc12fc R12: ffffed103b61d6c0
R13: 0000000000000200 R14: 0000000000082a20 R15: dffffc0000000000
FS:  00007ff1718816c0(0000) GS:ffff8881f6e00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007ff17321893f CR3: 00000001dab67000 CR4: 00000000003406b0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000090602
Call Trace:
 <IRQ>
 kasan_slab_alloc+0x12/0x20 mm/kasan/common.c:537
 slab_post_alloc_hook mm/slab.h:584 [inline]
 slab_alloc_node mm/slub.c:2829 [inline]
 slab_alloc mm/slub.c:2837 [inline]
 __kmalloc_track_caller+0x10d/0x2d0 mm/slub.c:4449
 __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_del_pg+0x262/0x3b0 net/bridge/br_multicast.c:186
 br_multicast_port_group_expired+0x174/0x1a0 net/bridge/br_multicast.c:210
 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:ffff8881d94af1a8 EFLAGS: 00000246 ORIG_RAX: ffffffffffffff13
RAX: 0000000000000001 RBX: dffffc0000000000 RCX: dffffc0000000000
RDX: 0000000040000000 RSI: 0000000000000000 RDI: 0000000000000001
RBP: ffff8881d94af1b0 R08: dffffc0000000000 R09: fffffbfff0c57781
R10: fffffbfff0c57781 R11: 1ffffffff0c57780 R12: ffff8881f6e57b40
R13: ffff8881f5dc4ef8 R14: 0000000000000000 R15: ffff8881d861bf00
 finish_lock_switch kernel/sched/core.c:3349 [inline]
 finish_task_switch+0x12e/0x590 kernel/sched/core.c:3449
 context_switch kernel/sched/core.c:3613 [inline]
 __schedule+0xa57/0x12a0 kernel/sched/core.c:4309
 preempt_schedule_irq+0x9b/0x110 kernel/sched/core.c:4560
 retint_kernel+0x1b/0x1b
RIP: 0010:__kernel_text_address+0xd2/0x100 kernel/extable.c:116
Code: 84 ff 75 05 e8 af 79 0e 00 45 84 e4 74 19 49 81 fe 00 70 34 86 0f 93 c0 49 81 fe 77 49 46 86 0f 92 c1 20 c1 0f b6 d9 89 d8 5b <41> 5c 41 5e 41 5f 5d c3 48 c7 c1 00 83 2b 86 80 e1 07 80 c1 03 38
RSP: 0018:ffff8881d94af458 EFLAGS: 00000202 ORIG_RAX: ffffffffffffff13
RAX: 0000000000000001 RBX: ffff8881d94af4f0 RCX: 6554029d78681a01
RDX: ffff8881d94afa10 RSI: 1ffff1103b295e96 RDI: ffffffff8138e3d3
RBP: ffff8881d94af470 R08: dffffc0000000000 R09: ffff8881d94af4a8
R10: ffffed103b295ea1 R11: 1ffff1103b295e95 R12: ffff8881d861bf00
R13: 1ffff1103b295ea8 R14: dffffc0000000000 R15: 1ffff1103b295e9e
 unwind_get_return_address+0x4d/0x90 arch/x86/kernel/unwind_frame.c:19
 arch_stack_walk+0xf0/0x140 arch/x86/kernel/stacktrace.c:26
 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
 syscall_return_slowpath arch/x86/entry/common.c:274 [inline]
 do_syscall_64+0x13e/0x170 arch/x86/entry/common.c:300
 entry_SYSCALL_64_after_hwframe+0x5c/0xc1
RIP: 0033:0x7ff173218969
Code: Bad RIP value.
RSP: 002b:00007ff171881038 EFLAGS: 00000246 ORIG_RAX: 0000000000000141
RAX: 0000000000000008 RBX: 00007ff17343ffa0 RCX: 00007ff173218969
RDX: 0000000000000048 RSI: 0000200000000240 RDI: 0000000000000000
RBP: 00007ff17329aab1 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007ff17343ffa0 R15: 00007fff6bb54d78
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1 skipped: idling at native_safe_halt arch/x86/include/asm/irqflags.h:60 [inline]
NMI backtrace for cpu 1 skipped: idling at arch_safe_halt arch/x86/include/asm/irqflags.h:103 [inline]
NMI backtrace for cpu 1 skipped: idling at default_idle+0x23/0x40 arch/x86/kernel/process.c:577

Crashes (2):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2025/04/27 14:40 android12-5.4 cd8e74fa0fa3 c6b4fb39 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-5-4-perf-kasan BUG: soft lockup in br_multicast_port_group_expired
2025/03/19 08:52 android12-5.4 41adfeb3d639 8d0a2921 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-5-4-perf-kasan BUG: soft lockup in br_multicast_port_group_expired
* Struck through repros no longer work on HEAD.