INFO: task syz.3.5531:16985 blocked for more than 122 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.3.5531 state:D stack:0 pid:16985 tgid:16985 ppid:12654 flags:0x00004006
Call Trace:
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_preempt_disabled+0x14/0x30 kernel/sched/core.c:7944
__mutex_lock_common kernel/locking/mutex.c:707 [inline]
__mutex_lock+0x81e/0x1b50 kernel/locking/mutex.c:803
__mutex_lock_slowpath+0xe/0x20 kernel/locking/mutex.c:1134
mutex_lock+0x102/0x1c0 kernel/locking/mutex.c:285
rcu_barrier+0x4d/0x530 kernel/rcu/tree.c:4589
kvm_mmu_uninit_tdp_mmu+0x1df/0x210 arch/x86/kvm/mmu/tdp_mmu.c:51
kvm_mmu_uninit_vm+0x27/0x60 arch/x86/kvm/mmu/mmu.c:6572
kvm_arch_destroy_vm+0x383/0x410 arch/x86/kvm/x86.c:12923
kvm_destroy_vm virt/kvm/kvm_main.c:1355 [inline]
kvm_put_kvm+0xb04/0x12c0 virt/kvm/kvm_main.c:1392
kvm_vm_release+0x47/0x70 virt/kvm/kvm_main.c:1415
__fput+0x1fb/0xa00 fs/file_table.c:429
____fput+0x20/0x30 fs/file_table.c:457
task_work_run+0x1e0/0x250 kernel/task_work.c:240
exit_task_work include/linux/task_work.h:43 [inline]
do_exit+0x9bc/0x2630 kernel/exit.c:953
do_group_exit+0x22a/0x300 kernel/exit.c:1095
get_signal+0x139d/0x14f0 kernel/signal.c:2933
arch_do_signal_or_restart+0x96/0x720 arch/x86/kernel/signal.c:337
exit_to_user_mode_loop kernel/entry/common.c:111 [inline]
exit_to_user_mode_prepare include/linux/entry-common.h:328 [inline]
__syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline]
syscall_exit_to_user_mode+0x58/0xb0 kernel/entry/common.c:218
do_syscall_64+0x64/0xf0 arch/x86/entry/common.c:89
entry_SYSCALL_64_after_hwframe+0x76/0x7e
RIP: 0033:0x7f053a9c1885
RSP: 002b:00007f053b80bf80 EFLAGS: 00000293 ORIG_RAX: 00000000000000e6
RAX: fffffffffffffdfc RBX: 00007f053abe6180 RCX: 00007f053a9c1885
RDX: 00007f053b80bfc0 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 00007f053aa11f91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000293 R12: 0000000000000000
R13: 00007f053abe6218 R14: 00007f053abe6180 R15: 00007fffc0b59f38
INFO: task syz.6.6130:18733 blocked for more than 129 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.6.6130 state:D stack:0 pid:18733 tgid:18733 ppid:15978 flags:0x00004006
Call Trace:
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_preempt_disabled+0x14/0x30 kernel/sched/core.c:7944
__mutex_lock_common kernel/locking/mutex.c:707 [inline]
__mutex_lock+0x81e/0x1b50 kernel/locking/mutex.c:803
__mutex_lock_slowpath+0xe/0x20 kernel/locking/mutex.c:1134
mutex_lock+0x102/0x1c0 kernel/locking/mutex.c:285
rcu_barrier+0x4d/0x530 kernel/rcu/tree.c:4589
netdev_run_todo+0x10e/0xcb0 net/core/dev.c:10880
rtnl_unlock+0x12/0x20 net/core/rtnetlink.c:152
tun_detach drivers/net/tun.c:704 [inline]
tun_chr_close+0xc5/0x150 drivers/net/tun.c:3517
__fput+0x1fb/0xa00 fs/file_table.c:429
____fput+0x20/0x30 fs/file_table.c:457
task_work_run+0x1e0/0x250 kernel/task_work.c:240
exit_task_work include/linux/task_work.h:43 [inline]
do_exit+0x9bc/0x2630 kernel/exit.c:953
do_group_exit+0x22a/0x300 kernel/exit.c:1095
get_signal+0x139d/0x14f0 kernel/signal.c:2933
arch_do_signal_or_restart+0x96/0x720 arch/x86/kernel/signal.c:337
exit_to_user_mode_loop kernel/entry/common.c:111 [inline]
exit_to_user_mode_prepare include/linux/entry-common.h:328 [inline]
__syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline]
syscall_exit_to_user_mode+0x58/0xb0 kernel/entry/common.c:218
do_syscall_64+0x64/0xf0 arch/x86/entry/common.c:89
entry_SYSCALL_64_after_hwframe+0x76/0x7e
RIP: 0033:0x7f4b295c1885
RSP: 002b:00007f4b2a3d3f80 EFLAGS: 00000293 ORIG_RAX: 00000000000000e6
RAX: fffffffffffffdfc RBX: 00007f4b297e5fa0 RCX: 00007f4b295c1885
RDX: 00007f4b2a3d3fc0 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 00007f4b29611f91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000293 R12: 0000000000000000
R13: 00007f4b297e6038 R14: 00007f4b297e5fa0 R15: 00007ffec8731898
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:
__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
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 8376 Comm: kworker/u8:12 Not tainted syzkaller #0 0b5ffdee5fcd2f7749818d1ff954e9c21353764e
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/02/2025
Workqueue: netns cleanup_net
RIP: 0010:check_kcov_mode kernel/kcov.c:183 [inline]
RIP: 0010:write_comp_data kernel/kcov.c:246 [inline]
RIP: 0010:__sanitizer_cov_trace_const_cmp8+0x2c/0x90 kernel/kcov.c:321
Code: 1e fa 55 48 89 e5 48 8b 45 08 65 48 8b 0c 25 00 eb 04 00 65 8b 15 5c e7 7e 7e 81 e2 00 01 ff 00 74 11 81 fa 00 01 00 00 75 57 <83> b9 ec 0b 00 00 00 74 4e 8b 91 c8 0b 00 00 83 fa 03 75 43 48 8b
RSP: 0018:ffffc90000007410 EFLAGS: 00000246
RAX: ffffffff84689157 RBX: ffff888182a30140 RCX: ffff88815b68a600
RDX: 0000000000000100 RSI: 0000000000000000 RDI: 0000000000000000
RBP: ffffc90000007410 R08: ffff888182a30237 R09: 1ffff11030546046
R10: dffffc0000000000 R11: ffffed1030546047 R12: dffffc0000000000
R13: 1ffff11030546033 R14: 0000000000000000 R15: 1ffff11030546034
FS: 0000000000000000(0000) GS:ffff8881f6e00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000555f73b7cb98 CR3: 0000000105f32000 CR4: 00000000003526b0
Call Trace:
nf_conntrack_put include/linux/netfilter/nf_conntrack_common.h:36 [inline]
skb_release_head_state+0x147/0x260 net/core/skbuff.c:1178
skb_release_all net/core/skbuff.c:1186 [inline]
__kfree_skb+0x29/0x210 net/core/skbuff.c:1202
consume_skb+0x65/0x1a0 net/core/skbuff.c:1434
netlink_broadcast_filtered+0x10e1/0x11f0 net/netlink/af_netlink.c:1530
nlmsg_multicast_filtered include/net/netlink.h:1125 [inline]
nlmsg_multicast include/net/netlink.h:1144 [inline]
nlmsg_notify+0xf1/0x1b0 net/netlink/af_netlink.c:2588
rtnl_notify+0x9e/0xd0 net/core/rtnetlink.c:786
fdb_notify+0xce/0x150 net/bridge/br_fdb.c:206
br_fdb_update+0x4b7/0x680 net/bridge/br_fdb.c:941
br_handle_frame_finish+0x39c/0x1720 net/bridge/br_input.c:141
nf_hook_bridge_pre net/bridge/br_input.c:301 [inline]
br_handle_frame+0x5a6/0xba0 net/bridge/br_input.c:424
__netif_receive_skb_core+0xf4b/0x3940 net/core/dev.c:5663
__netif_receive_skb_one_core net/core/dev.c:5767 [inline]
__netif_receive_skb net/core/dev.c:5882 [inline]
process_backlog+0x3e5/0xae0 net/core/dev.c:6218
__napi_poll+0xd3/0x610 net/core/dev.c:6869
napi_poll net/core/dev.c:6938 [inline]
net_rx_action+0x584/0xce0 net/core/dev.c:7060
handle_softirqs+0x1ab/0x630 kernel/softirq.c:621
__do_softirq+0xf/0x16 kernel/softirq.c:659
do_softirq+0xa6/0x100 kernel/softirq.c:503
__local_bh_enable_ip+0x74/0x80 kernel/softirq.c:430
__raw_spin_unlock_bh include/linux/spinlock_api_smp.h:167 [inline]
_raw_spin_unlock_bh+0x54/0x60 kernel/locking/spinlock.c:210
spin_unlock_bh include/linux/spinlock.h:396 [inline]
addrconf_ifdown+0x608/0x1940 net/ipv6/addrconf.c:3950
addrconf_notify+0x17a/0xea0 net/ipv6/addrconf.c:-1
notifier_call_chain+0x10b/0x2c0 kernel/notifier.c:93
raw_notifier_call_chain+0x31/0x40 kernel/notifier.c:461
call_netdevice_notifiers_info net/core/dev.c:2067 [inline]
call_netdevice_notifiers_extack net/core/dev.c:2105 [inline]
call_netdevice_notifiers net/core/dev.c:2119 [inline]
unregister_netdevice_many_notify+0xe32/0x1bd0 net/core/dev.c:11501
unregister_netdevice_many+0x1d/0x30 net/core/dev.c:11563
cleanup_net+0x62d/0xc70 net/core/net_namespace.c:637
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