syzbot

watchdog: BUG: soft lockup - CPU#1 stuck for 120s! [syz.6.703:8706]
Modules linked in:
irq event stamp: 16471041
hardirqs last  enabled at (16471040): [<ffffffff8b472c44>] irqentry_exit+0x74/0x90 kernel/entry/common.c:214
hardirqs last disabled at (16471041): [<ffffffff8b47187e>] sysvec_apic_timer_interrupt+0xe/0xc0 arch/x86/kernel/apic/apic.c:1052
softirqs last  enabled at (15864500): [<ffffffff8183ee9a>] __do_softirq kernel/softirq.c:656 [inline]
softirqs last  enabled at (15864500): [<ffffffff8183ee9a>] invoke_softirq kernel/softirq.c:496 [inline]
softirqs last  enabled at (15864500): [<ffffffff8183ee9a>] __irq_exit_rcu+0xca/0x1f0 kernel/softirq.c:723
softirqs last disabled at (15864503): [<ffffffff8183ee9a>] __do_softirq kernel/softirq.c:656 [inline]
softirqs last disabled at (15864503): [<ffffffff8183ee9a>] invoke_softirq kernel/softirq.c:496 [inline]
softirqs last disabled at (15864503): [<ffffffff8183ee9a>] __irq_exit_rcu+0xca/0x1f0 kernel/softirq.c:723
CPU: 1 UID: 0 PID: 8706 Comm: syz.6.703 Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/18/2025
RIP: 0010:do_perf_trace_lock include/trace/events/lock.h:50 [inline]
RIP: 0010:perf_trace_lock+0x10b/0x3b0 include/trace/events/lock.h:50
Code: 03 48 89 44 24 10 e8 c4 78 ab 09 89 c3 83 f8 08 0f 83 4a 02 00 00 48 8d 1c dd d0 5d a0 8d 48 89 d8 48 c1 e8 03 42 80 3c 38 00 <74> 08 48 89 df e8 8b 04 89 00 4c 89 74 24 38 49 83 c6 68 4c 89 f0
RSP: 0018:ffffc90000a07860 EFLAGS: 00000246
RAX: 1ffffffff1b40bbb RBX: ffffffff8da05dd8 RCX: 74107bbd4e4e6000
RDX: ffffffff8172ad45 RSI: ffffffff8bc060c0 RDI: ffffffff8bc06080
RBP: ffffc90000a07960 R08: ffffc90000a08790 R09: 0000000000000000
R10: ffffc90000a07af8 R11: fffff52000140f61 R12: 1ffff92000140f14
R13: 000000000000000d R14: ffffffff8e00a0c0 R15: dffffc0000000000
FS:  00007fe03b6906c0(0000) GS:ffff888125e27000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f8902fd4f98 CR3: 00000000279e6000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000ffff0ff1 DR7: 0000000000000600
Call Trace:
 <IRQ>
 __do_trace_lock_release include/trace/events/lock.h:69 [inline]
 trace_lock_release include/trace/events/lock.h:69 [inline]
 lock_release+0x3b2/0x3e0 kernel/locking/lockdep.c:5879
 rcu_lock_release include/linux/rcupdate.h:341 [inline]
 rcu_read_unlock include/linux/rcupdate.h:871 [inline]
 class_rcu_destructor include/linux/rcupdate.h:1169 [inline]
 unwind_next_frame+0x19a9/0x2390 arch/x86/kernel/unwind_orc.c:680
 arch_stack_walk+0x11c/0x150 arch/x86/kernel/stacktrace.c:25
 stack_trace_save+0x9c/0xe0 kernel/stacktrace.c:122
 kasan_save_stack mm/kasan/common.c:56 [inline]
 kasan_save_track+0x3e/0x80 mm/kasan/common.c:77
 __kasan_save_free_info+0x46/0x50 mm/kasan/generic.c:587
 kasan_save_free_info mm/kasan/kasan.h:406 [inline]
 poison_slab_object mm/kasan/common.c:252 [inline]
 __kasan_slab_free+0x5c/0x80 mm/kasan/common.c:284
 kasan_slab_free include/linux/kasan.h:234 [inline]
 slab_free_hook mm/slub.c:2514 [inline]
 slab_free mm/slub.c:6566 [inline]
 kmem_cache_free+0x19b/0x690 mm/slub.c:6676
 kfree_skb_reason include/linux/skbuff.h:1322 [inline]
 ip6_rcv_core+0x9f0/0x1590 net/ipv6/ip6_input.c:-1
 ipv6_rcv+0x72/0xc0 net/ipv6/ip6_input.c:308
 __netif_receive_skb_one_core net/core/dev.c:6079 [inline]
 __netif_receive_skb+0xd3/0x380 net/core/dev.c:6192
 netif_receive_skb_internal net/core/dev.c:6278 [inline]
 netif_receive_skb+0x1cb/0x790 net/core/dev.c:6337
 NF_HOOK+0x9d/0x390 include/linux/netfilter.h:319
 br_handle_frame_finish+0x15c6/0x1c50 net/bridge/br_input.c:235
 br_nf_hook_thresh+0x3c6/0x4a0 net/bridge/br_netfilter_hooks.c:-1
 br_nf_pre_routing_finish_ipv6+0x999/0xd60 net/bridge/br_netfilter_ipv6.c:-1
 NF_HOOK include/linux/netfilter.h:318 [inline]
 br_nf_pre_routing_ipv6+0x37e/0x6b0 net/bridge/br_netfilter_ipv6.c:184
 nf_hook_entry_hookfn include/linux/netfilter.h:158 [inline]
 nf_hook_bridge_pre net/bridge/br_input.c:291 [inline]
 br_handle_frame+0x97f/0x14c0 net/bridge/br_input.c:442
 __netif_receive_skb_core+0x10b9/0x4380 net/core/dev.c:5966
 __netif_receive_skb_one_core net/core/dev.c:6077 [inline]
 __netif_receive_skb+0x72/0x380 net/core/dev.c:6192
 process_backlog+0x60e/0x14f0 net/core/dev.c:6544
 __napi_poll+0xc7/0x360 net/core/dev.c:7594
 napi_poll net/core/dev.c:7657 [inline]
 net_rx_action+0x5f7/0xdf0 net/core/dev.c:7784
 handle_softirqs+0x283/0x870 kernel/softirq.c:622
 __do_softirq kernel/softirq.c:656 [inline]
 invoke_softirq kernel/softirq.c:496 [inline]
 __irq_exit_rcu+0xca/0x1f0 kernel/softirq.c:723
 irq_exit_rcu+0x9/0x30 kernel/softirq.c:739
 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1052 [inline]
 sysvec_apic_timer_interrupt+0xa6/0xc0 arch/x86/kernel/apic/apic.c:1052
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702
RIP: 0010:__schedule+0x17a2/0x4cc0 kernel/sched/core.c:6885
Code: 74 08 48 89 df e8 3e b9 dc f6 48 8b 44 24 08 48 89 03 48 89 c3 4c 89 f7 48 89 c6 e8 78 10 eb f5 48 89 c7 e8 a0 1a 48 f6 31 ff <49> 39 de 40 0f 95 c7 e8 f2 23 48 f6 48 c7 84 24 00 01 00 00 0e 36
RSP: 0018:ffffc9000f1ff7c0 EFLAGS: 00000246
RAX: 0000000000000001 RBX: ffff88801caabc80 RCX: ffffffff81902cbb
RDX: 0000000000000001 RSI: 0000000000000004 RDI: 0000000000000000
RBP: ffffc9000f1ff9d8 R08: ffff88807f0e9583 R09: 1ffff1100fe1d2b0
R10: dffffc0000000000 R11: ffffed100fe1d2b1 R12: dffffc0000000000
R13: 1ffff110170e756e R14: ffff88802493dac0 R15: ffff88801caad254
 __schedule_loop kernel/sched/core.c:7011 [inline]
 schedule+0x165/0x360 kernel/sched/core.c:7026
 futex_do_wait kernel/futex/waitwake.c:358 [inline]
 __futex_wait+0x1c3/0x3d0 kernel/futex/waitwake.c:687
 futex_wait+0x104/0x360 kernel/futex/waitwake.c:715
 do_futex+0x333/0x420 kernel/futex/syscalls.c:130
 __do_sys_futex kernel/futex/syscalls.c:207 [inline]
 __se_sys_futex+0x36f/0x400 kernel/futex/syscalls.c:188
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xfa/0xfa0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fe03a78eec9
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:00007fe03b6900e8 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca
RAX: ffffffffffffffda RBX: 00007fe03a9e5fa8 RCX: 00007fe03a78eec9
RDX: 0000000000000000 RSI: 0000000000000080 RDI: 00007fe03a9e5fa8
RBP: 00007fe03a9e5fa0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fe03a9e6038 R14: 00007ffc3e7c6590 R15: 00007ffc3e7c6678
 </TASK>
Sending NMI from CPU 1 to CPUs 0:
bridge0: received packet on team0 with own address as source address (addr:aa:aa:aa:aa:aa:20, vlan:0)
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 8718 Comm: syz.1.705 Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/18/2025
RIP: 0010:prb_read kernel/printk/printk_ringbuffer.c:1932 [inline]
RIP: 0010:_prb_read_valid+0x4fe/0xa90 kernel/printk/printk_ringbuffer.c:2113
Code: 48 85 c0 0f 84 4a 05 00 00 48 89 c3 48 c1 eb 03 42 80 3c 23 00 74 0f 48 8b 7c 24 48 e8 4b 42 84 00 48 8b 44 24 48 48 83 38 00 <74> 2b e8 6b 9f 1e 00 42 80 3c 23 00 48 8b 5c 24 48 74 08 48 89 df
RSP: 0018:ffffc90000006900 EFLAGS: 00000282
RAX: ffffc90000006c00 RBX: 1ffff92000000d80 RCX: ffff88802697dac0
RDX: 0000000000000100 RSI: ffffffffffff91a8 RDI: 0000000000000001
RBP: ffffc90000006a80 R08: ffff88802697dac0 R09: 0000000000000003
R10: 00000000ffffffff R11: 0000000000000100 R12: dffffc0000000000
R13: 00000000ffffed42 R14: ffffffff8e09bf30 R15: ffffc90000006a90
FS:  00007f8ebc0a06c0(0000) GS:ffff888125d27000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000001b30724000 CR3: 0000000065498000 CR4: 00000000003526f0
DR0: 0000200000000300 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000600
Call Trace:
 <IRQ>
 prb_read_valid+0x3c/0x60 kernel/printk/printk_ringbuffer.c:2185
 printk_get_next_message+0x15c/0x7b0 kernel/printk/printk.c:2978
 console_emit_next_record kernel/printk/printk.c:3065 [inline]
 console_flush_all+0x4ca/0xb10 kernel/printk/printk.c:3199
 __console_flush_and_unlock kernel/printk/printk.c:3258 [inline]
 console_unlock+0xbb/0x190 kernel/printk/printk.c:3298
 vprintk_emit+0x4c5/0x590 kernel/printk/printk.c:2423
 _printk+0xcf/0x120 kernel/printk/printk.c:2448
 br_fdb_update+0x62d/0x690 net/bridge/br_fdb.c:999
 br_handle_frame_finish+0x587/0x1c50 net/bridge/br_input.c:144
 br_nf_hook_thresh+0x3c6/0x4a0 net/bridge/br_netfilter_hooks.c:-1
 br_nf_pre_routing_finish_ipv6+0x999/0xd60 net/bridge/br_netfilter_ipv6.c:-1
 NF_HOOK include/linux/netfilter.h:318 [inline]
 br_nf_pre_routing_ipv6+0x37e/0x6b0 net/bridge/br_netfilter_ipv6.c:184
 nf_hook_entry_hookfn include/linux/netfilter.h:158 [inline]
 nf_hook_bridge_pre net/bridge/br_input.c:291 [inline]
 br_handle_frame+0x97f/0x14c0 net/bridge/br_input.c:442
 __netif_receive_skb_core+0x10b9/0x4380 net/core/dev.c:5966
 __netif_receive_skb_one_core net/core/dev.c:6077 [inline]
 __netif_receive_skb+0x72/0x380 net/core/dev.c:6192
 process_backlog+0x60e/0x14f0 net/core/dev.c:6544
 __napi_poll+0xc7/0x360 net/core/dev.c:7594
 napi_poll net/core/dev.c:7657 [inline]
 net_rx_action+0x5f7/0xdf0 net/core/dev.c:7784
 handle_softirqs+0x283/0x870 kernel/softirq.c:622
 __do_softirq kernel/softirq.c:656 [inline]
 invoke_softirq kernel/softirq.c:496 [inline]
 __irq_exit_rcu+0xca/0x1f0 kernel/softirq.c:723
 irq_exit_rcu+0x9/0x30 kernel/softirq.c:739
 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1052 [inline]
 sysvec_apic_timer_interrupt+0xa6/0xc0 arch/x86/kernel/apic/apic.c:1052
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702
RIP: 0010:filter_irq_stacks+0x29/0xa0 kernel/stacktrace.c:397
Code: 90 f3 0f 1e fa 41 57 41 56 41 55 41 54 53 85 f6 74 70 49 89 fe 41 89 f4 31 db 49 bd 00 00 00 00 00 fc ff df 49 89 ff 4c 89 f8 <48> c1 e8 03 42 80 3c 28 00 74 08 4c 89 ff e8 14 6e 79 00 49 8b 04
RSP: 0018:ffffc9000f2df4b8 EFLAGS: 00000202
RAX: ffffc9000f2df5d8 RBX: 0000000000000011 RCX: 0000000000000001
RDX: 0000000000000000 RSI: 0000000000000012 RDI: ffffc9000f2df550
RBP: ffffc9000f2df778 R08: ffffc9000f2def97 R09: 0000000000000000
R10: ffffc9000f2def88 R11: fffff52001e5bdf3 R12: 0000000000000012
R13: dffffc0000000000 R14: ffffc9000f2df550 R15: ffffc9000f2df5d8
 stack_depot_save_flags+0x40/0x860 lib/stackdepot.c:659
 kasan_save_stack+0x4d/0x60 mm/kasan/common.c:57
 kasan_record_aux_stack+0xbd/0xd0 mm/kasan/generic.c:559
 __call_rcu_common kernel/rcu/tree.c:3123 [inline]
 call_rcu+0x157/0x9c0 kernel/rcu/tree.c:3243
 context_switch kernel/sched/core.c:5328 [inline]
 __schedule+0x17a0/0x4cc0 kernel/sched/core.c:6929
 preempt_schedule_notrace+0xd1/0x110 kernel/sched/core.c:7206
 preempt_schedule_notrace_thunk+0x16/0x30 arch/x86/entry/thunk.S:13
 rcu_is_watching+0x7f/0xb0 kernel/rcu/tree.c:752
 rcu_read_lock include/linux/rcupdate.h:842 [inline]
 percpu_ref_tryget_many include/linux/percpu-refcount.h:241 [inline]
 percpu_ref_tryget+0x43/0x180 include/linux/percpu-refcount.h:266
 css_tryget include/linux/cgroup_refcnt.h:45 [inline]
 get_mem_cgroup_from_objcg+0x108/0x1d0 include/linux/memcontrol.h:519
 __memcg_slab_post_alloc_hook+0x12a/0x7d0 mm/memcontrol.c:3160
 memcg_slab_post_alloc_hook mm/slub.c:2313 [inline]
 slab_post_alloc_hook mm/slub.c:4957 [inline]
 slab_alloc_node mm/slub.c:5245 [inline]
 kmem_cache_alloc_lru_noprof+0x410/0x6d0 mm/slub.c:5264
 sock_alloc_inode+0x28/0xc0 net/socket.c:322
 alloc_inode+0x6a/0x1b0 fs/inode.c:346
 new_inode_pseudo include/linux/fs.h:3394 [inline]
 sock_alloc net/socket.c:637 [inline]
 __sock_create+0x12d/0x9f0 net/socket.c:1569
 sock_create net/socket.c:1663 [inline]
 __sys_socket_create net/socket.c:1700 [inline]
 __sys_socket+0xd7/0x1b0 net/socket.c:1747
 __do_sys_socket net/socket.c:1761 [inline]
 __se_sys_socket net/socket.c:1759 [inline]
 __x64_sys_socket+0x7a/0x90 net/socket.c:1759
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xfa/0xfa0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f8ebb18eec9
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:00007f8ebc0a0038 EFLAGS: 00000246 ORIG_RAX: 0000000000000029
RAX: ffffffffffffffda RBX: 00007f8ebb3e5fa0 RCX: 00007f8ebb18eec9
RDX: 0000000000000000 RSI: 0000000000000003 RDI: 0000000000000010
RBP: 00007f8ebb211f91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f8ebb3e6038 R14: 00007f8ebb3e5fa0 R15: 00007ffff6e29788
 </TASK>