INFO: task kworker/u8:1:13 blocked for more than 122 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:kworker/u8:1    state:D stack:0     pid:13    tgid:13    ppid:2      flags:0x00004000
Workqueue: netns cleanup_net
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5945 [inline]
 __schedule+0x1322/0x1df0 kernel/sched/core.c:7791
 __schedule_loop kernel/sched/core.c:7872 [inline]
 schedule+0xc6/0x240 kernel/sched/core.c:7887
 schedule_timeout+0xb2/0x3a0 kernel/time/timer.c:2595
 do_wait_for_common kernel/sched/completion.c:95 [inline]
 __wait_for_common kernel/sched/completion.c:116 [inline]
 wait_for_common+0x359/0x630 kernel/sched/completion.c:127
 wait_for_completion+0x1c/0x40 kernel/sched/completion.c:148
 rcu_barrier+0x415/0x530 kernel/rcu/tree.c:4657
 netdev_run_todo+0x10e/0xcb0 net/core/dev.c:10880
 rtnl_unlock+0x12/0x20 net/core/rtnetlink.c:152
 cleanup_net+0x632/0xc70 net/core/net_namespace.c:638
 process_one_work kernel/workqueue.c:3238 [inline]
 process_scheduled_works+0x7d2/0x1020 kernel/workqueue.c:3319
 worker_thread+0xc58/0x1250 kernel/workqueue.c:3400
 kthread+0x2ca/0x370 kernel/kthread.c:389
 ret_from_fork+0x67/0xa0 arch/x86/kernel/process.c:153
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
 </TASK>
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 37 Comm: khungtaskd Not tainted syzkaller #0 0b5ffdee5fcd2f7749818d1ff954e9c21353764e
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/02/2025
Call Trace:
 <TASK>
 __dump_stack+0x21/0x30 lib/dump_stack.c:94
 dump_stack_lvl+0x10c/0x190 lib/dump_stack.c:120
 dump_stack+0x19/0x20 lib/dump_stack.c:129
 nmi_cpu_backtrace+0x2bf/0x2d0 lib/nmi_backtrace.c:113
 nmi_trigger_cpumask_backtrace+0x142/0x2c0 lib/nmi_backtrace.c:62
 arch_trigger_cpumask_backtrace+0x14/0x20 arch/x86/kernel/apic/hw_nmi.c:41
 trigger_all_cpu_backtrace include/linux/nmi.h:158 [inline]
 check_hung_uninterruptible_tasks kernel/hung_task.c:267 [inline]
 watchdog+0xd8f/0xed0 kernel/hung_task.c:423
 kthread+0x2ca/0x370 kernel/kthread.c:389
 ret_from_fork+0x67/0xa0 arch/x86/kernel/process.c:153
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
 </TASK>
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 281 Comm: sshd-session Not tainted syzkaller #0 0b5ffdee5fcd2f7749818d1ff954e9c21353764e
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/02/2025
RIP: 0010:instrument_atomic_read include/linux/instrumented.h:68 [inline]
RIP: 0010:atomic_read include/linux/atomic/atomic-instrumented.h:32 [inline]
RIP: 0010:perf_event_task kernel/events/core.c:8492 [inline]
RIP: 0010:perf_event_exit_task+0x73b/0x8c0 kernel/events/core.c:13579
Code: e8 0a 85 ce ff 4c 89 f3 eb d0 e8 00 85 ce ff eb 05 e8 f9 84 ce ff 48 8b 7c 24 20 e8 ff e1 d6 03 48 8b 7c 24 10 e8 c5 2c fe ff <48> c7 c7 a4 28 cb 87 be 04 00 00 00 e8 24 f5 24 00 8b 1d c2 ae 13
RSP: 0018:ffffc900010ffbc0 EFLAGS: 00000293
RAX: ffffffff81b77571 RBX: ffff8881295db148 RCX: ffff8881295da600
RDX: 0000000000000000 RSI: 0000000000000200 RDI: 0000000000000000
RBP: ffffc900010ffd10 R08: ffffc900010ffb47 R09: 1ffff9200021ff68
R10: dffffc0000000000 R11: fffff5200021ff69 R12: 0020000000000004
R13: dffffc0000000000 R14: ffff8881295db148 R15: dffffc0000000000
FS:  00007f87ad948300(0000) GS:ffff8881f6e00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000561d482d6b90 CR3: 000000010ae86000 CR4: 00000000003526b0
Call Trace:
 <TASK>
 do_exit+0x7d9/0x2630 kernel/exit.c:938
 do_group_exit+0x22a/0x300 kernel/exit.c:1095
 __do_sys_exit_group kernel/exit.c:1106 [inline]
 __se_sys_exit_group kernel/exit.c:1104 [inline]
 __x64_sys_exit_group+0x43/0x50 kernel/exit.c:1104
 x64_sys_call+0x2ed2/0x2ee0 arch/x86/include/generated/asm/syscalls_64.h:232
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0x58/0xf0 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x76/0x7e
RIP: 0033:0x7f87ad2a76c5
Code: ff ff ff 64 89 02 eb d2 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 00 48 8b 35 21 f7 0f 00 ba e7 00 00 00 eb 03 66 90 f4 89 d0 0f 05 <48> 3d 00 f0 ff ff 76 f3 f7 d8 64 89 06 eb ec 66 2e 0f 1f 84 00 00
RSP: 002b:00007ffc42a3c7e8 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7
RAX: ffffffffffffffda RBX: 00000000000000ff RCX: 00007f87ad2a76c5
RDX: 00000000000000e7 RSI: fffffffffffffea0 RDI: 00000000000000ff
RBP: 00007ffc42a3c930 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00007f87ad9481a0
R13: 00000000ffffffe3 R14: 00007ffc42a3cb80 R15: 000000000000000a
 </TASK>
net_ratelimit: 138152 callbacks suppressed
bridge0: received packet on bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0)
bridge0: received packet on veth0_to_bridge with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0)
bridge0: received packet on veth0_to_bridge with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0)
bridge0: received packet on veth0_to_bridge with own address as source address (addr:ba:f2:17:22:ef:bb, vlan:0)
bridge0: received packet on veth0_to_bridge with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0)
bridge0: received packet on veth0_to_bridge with own address as source address (addr:ba:f2:17:22:ef:bb, vlan:0)
bridge0: received packet on bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0)
bridge0: received packet on veth0_to_bridge with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0)
bridge0: received packet on bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0)
bridge0: received packet on bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:1b, vlan:0)