INFO: task syz.2.2634:14325 blocked for more than 143 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.2.2634 state:D stack:25096 pid:14325 ppid: 4190 flags:0x00004002
Call Trace:
context_switch kernel/sched/core.c:5049 [inline]
__schedule+0x11bb/0x4390 kernel/sched/core.c:6395
schedule+0x11b/0x1e0 kernel/sched/core.c:6478
perf_pending_task_sync+0x13c/0x1c0 kernel/events/core.c:5127
_free_event+0x34/0xe60 kernel/events/core.c:5133
put_event kernel/events/core.c:5258 [inline]
perf_event_release_kernel+0x832/0x8c0 kernel/events/core.c:5383
perf_release+0x37/0x40 kernel/events/core.c:5393
__fput+0x234/0x930 fs/file_table.c:311
task_work_run+0x125/0x1a0 kernel/task_work.c:188
exit_task_work include/linux/task_work.h:33 [inline]
do_exit+0x61e/0x20a0 kernel/exit.c:883
do_group_exit+0x12e/0x300 kernel/exit.c:997
get_signal+0x6ca/0x12c0 kernel/signal.c:2900
arch_do_signal_or_restart+0xc1/0x1300 arch/x86/kernel/signal.c:867
handle_signal_work kernel/entry/common.c:154 [inline]
exit_to_user_mode_loop+0x9e/0x130 kernel/entry/common.c:178
exit_to_user_mode_prepare+0xee/0x180 kernel/entry/common.c:214
__syscall_exit_to_user_mode_work kernel/entry/common.c:296 [inline]
syscall_exit_to_user_mode+0x16/0x40 kernel/entry/common.c:307
do_syscall_64+0x58/0xa0 arch/x86/entry/common.c:86
entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7f10a00d4749
RSP: 002b:00007f109e33b038 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: 0000000000000012 RBX: 00007f10a032afa0 RCX: 00007f10a00d4749
RDX: 0000000000000012 RSI: 00002000000001c0 RDI: 000000000000000d
RBP: 00007f10a0158f91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f10a032b038 R14: 00007f10a032afa0 R15: 00007ffe76a4e6a8
Showing all locks held in the system:
3 locks held by kworker/0:0/7:
#0: ffff88802af4a138 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_one_work+0x760/0x1000 kernel/workqueue.c:-1
#1: ffffffff8c11c720 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire+0x9/0x30 include/linux/rcupdate.h:313
#2: ffff8880b90280d8 (&base->lock){-.-.}-{2:2}, at: lock_timer_base+0x123/0x270 kernel/time/timer.c:946
1 lock held by khungtaskd/27:
#0: ffffffff8c11c720 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire+0x0/0x30
2 locks held by getty/3946:
#0: ffff88814cdba098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x21/0x70 drivers/tty/tty_ldisc.c:252
#1: ffffc90002cf62e8 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x5ba/0x1a30 drivers/tty/n_tty.c:2158
3 locks held by kworker/0:8/4248:
#0: ffff888016870938 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x760/0x1000 kernel/workqueue.c:-1
#1: ffffc9000320fd00 ((work_completion)(&map->work)){+.+.}-{0:0}, at: process_one_work+0x7a3/0x1000 kernel/workqueue.c:2285
#2: ffffffff8c1210b0 (rcu_state.barrier_mutex){+.+.}-{3:3}, at: rcu_barrier+0xa1/0x4b0 kernel/rcu/tree.c:4043
3 locks held by kworker/1:12/7691:
#0: ffff888016870938 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x760/0x1000 kernel/workqueue.c:-1
#1: ffffc9000337fd00 (fqdir_free_work){+.+.}-{0:0}, at: process_one_work+0x7a3/0x1000 kernel/workqueue.c:2285
#2: ffffffff8c1210b0 (rcu_state.barrier_mutex){+.+.}-{3:3}, at: rcu_barrier+0xa1/0x4b0 kernel/rcu/tree.c:4043
3 locks held by kworker/u4:20/8512:
#0: ffff8880169cd938 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work+0x760/0x1000 kernel/workqueue.c:-1
#1: ffffc9000414fd00 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work+0x7a3/0x1000 kernel/workqueue.c:2285
#2: ffffffff8c1210b0 (rcu_state.barrier_mutex){+.+.}-{3:3}, at: rcu_barrier+0xa1/0x4b0 kernel/rcu/tree.c:4043
1 lock held by syz.5.3712/18473:
#0: ffffffff8c1210b0 (rcu_state.barrier_mutex){+.+.}-{3:3}, at: rcu_barrier+0xa1/0x4b0 kernel/rcu/tree.c:4043
=============================================
NMI backtrace for cpu 0
CPU: 0 PID: 27 Comm: khungtaskd Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
Call Trace:
dump_stack_lvl+0x168/0x230 lib/dump_stack.c:106
nmi_cpu_backtrace+0x397/0x3d0 lib/nmi_backtrace.c:111
nmi_trigger_cpumask_backtrace+0x163/0x280 lib/nmi_backtrace.c:62
trigger_all_cpu_backtrace include/linux/nmi.h:148 [inline]
check_hung_uninterruptible_tasks kernel/hung_task.c:212 [inline]
watchdog+0xe0f/0xe50 kernel/hung_task.c:369
kthread+0x436/0x520 kernel/kthread.c:334
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 PID: 20 Comm: ksoftirqd/1 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
RIP: 0010:__sanitizer_cov_trace_const_cmp2+0x0/0x80 kernel/kcov.c:287
Code: 28 4d 39 ca 77 22 89 ff 89 f6 4a c7 44 02 08 01 00 00 00 4a 89 7c 02 10 4a 89 74 02 18 4a 89 44 02 20 48 ff c1 48 89 0a c3 90 <48> 8b 04 24 65 48 8b 0d c4 a0 8a 7e 65 8b 15 c5 a0 8a 7e 81 e2 00
RSP: 0018:ffffc90000da6898 EFLAGS: 00000246
RAX: 0000000000000000 RBX: 0000000000000000 RCX: ffff88813fe60000
RDX: 0000000000000100 RSI: 0000000000000000 RDI: 0000000000000000
RBP: ffff88805ff5dd48 R08: ffff88813fe60000 R09: 0000000000000002
R10: 0000000000000002 R11: 0000000000000100 R12: ffff88805ff5dc80
R13: 00000000000005dc R14: ffff8880250de0c4 R15: dffffc0000000000
FS: 0000000000000000(0000) GS:ffff8880b9100000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fced2754000 CR3: 000000000be8e000 CR4: 00000000003506e0
DR0: 0000200000000300 DR1: 0000200000000300 DR2: 0000200000000300
DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000600
Call Trace:
skb_is_gso include/linux/skbuff.h:4697 [inline]
br_nf_dev_queue_xmit+0x3f9/0x1c30 net/bridge/br_netfilter_hooks.c:847
NF_HOOK+0x590/0x610 include/linux/netfilter.h:302
br_nf_post_routing+0x915/0xcb0 net/bridge/br_netfilter_hooks.c:955
nf_hook_entry_hookfn include/linux/netfilter.h:142 [inline]
nf_hook_slow+0xb9/0x200 net/netfilter/core.c:584
nf_hook include/linux/netfilter.h:257 [inline]
NF_HOOK+0x1eb/0x370 include/linux/netfilter.h:300
br_forward_finish+0x74/0x80 net/bridge/br_forward.c:66
br_nf_hook_thresh net/bridge/br_netfilter_hooks.c:-1 [inline]
br_nf_forward_finish+0x986/0xd20 net/bridge/br_netfilter_hooks.c:662
NF_HOOK+0x590/0x610 include/linux/netfilter.h:302
br_nf_forward_ip+0xc5c/0x10a0 net/bridge/br_netfilter_hooks.c:732
nf_hook_entry_hookfn include/linux/netfilter.h:142 [inline]
nf_hook_slow+0xb9/0x200 net/netfilter/core.c:584
nf_hook include/linux/netfilter.h:257 [inline]
NF_HOOK+0x1eb/0x370 include/linux/netfilter.h:300
__br_forward+0x41f/0x600 net/bridge/br_forward.c:115
br_handle_frame_finish+0x1018/0x12c0 net/bridge/br_input.c:180
br_nf_hook_thresh+0x3b2/0x480 net/bridge/br_netfilter_hooks.c:1155
br_nf_pre_routing_finish_ipv6+0x903/0xc80 net/bridge/br_netfilter_ipv6.c:-1
NF_HOOK include/linux/netfilter.h:302 [inline]
br_nf_pre_routing_ipv6+0x359/0x650 net/bridge/br_netfilter_ipv6.c:237
nf_hook_entry_hookfn include/linux/netfilter.h:142 [inline]
nf_hook_bridge_pre net/bridge/br_input.c:242 [inline]
br_handle_frame+0x89b/0x1180 net/bridge/br_input.c:384
__netif_receive_skb_core+0xfb0/0x35d0 net/core/dev.c:5419
__netif_receive_skb_one_core net/core/dev.c:5523 [inline]
__netif_receive_skb+0x74/0x290 net/core/dev.c:5639
process_backlog+0x364/0x780 net/core/dev.c:6516
__napi_poll+0xc0/0x430 net/core/dev.c:7075
napi_poll net/core/dev.c:7142 [inline]
net_rx_action+0x4a8/0x9c0 net/core/dev.c:7232
handle_softirqs+0x328/0x820 kernel/softirq.c:576
run_ksoftirqd+0x98/0xf0 kernel/softirq.c:943
smpboot_thread_fn+0x4f6/0x970 kernel/smpboot.c:164
kthread+0x436/0x520 kernel/kthread.c:334
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287