INFO: task syz.2.929:9587 blocked for more than 143 seconds.
Not tainted syzkaller #0
Blocked by coredump.
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.2.929 state:D stack:24104 pid:9587 tgid:9586 ppid:5849 task_flags:0x400548 flags:0x00080000
Call Trace:
context_switch kernel/sched/core.c:5325 [inline]
__schedule+0x1798/0x4cc0 kernel/sched/core.c:6929
__schedule_loop kernel/sched/core.c:7011 [inline]
schedule+0x165/0x360 kernel/sched/core.c:7026
schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7083
__mutex_lock_common kernel/locking/mutex.c:676 [inline]
__mutex_lock+0x7e6/0x1350 kernel/locking/mutex.c:760
io_uring_del_tctx_node+0xf0/0x2c0 io_uring/tctx.c:179
io_uring_clean_tctx+0xd4/0x1a0 io_uring/tctx.c:195
io_uring_cancel_generic+0x6ca/0x7d0 io_uring/io_uring.c:3327
io_uring_files_cancel include/linux/io_uring.h:19 [inline]
do_exit+0x345/0x2300 kernel/exit.c:912
do_group_exit+0x21c/0x2d0 kernel/exit.c:1107
get_signal+0x1285/0x1340 kernel/signal.c:3034
arch_do_signal_or_restart+0xa0/0x790 arch/x86/kernel/signal.c:337
exit_to_user_mode_loop+0x72/0x130 kernel/entry/common.c:40
exit_to_user_mode_prepare include/linux/irq-entry-common.h:225 [inline]
syscall_exit_to_user_mode_work include/linux/entry-common.h:175 [inline]
syscall_exit_to_user_mode include/linux/entry-common.h:210 [inline]
do_syscall_64+0x2bd/0xfa0 arch/x86/entry/syscall_64.c:100
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7ff01238efc9
RSP: 002b:00007ff01323a038 EFLAGS: 00000246 ORIG_RAX: 000000000000002c
RAX: 0000000000000001 RBX: 00007ff0125e5fa0 RCX: 00007ff01238efc9
RDX: 0000000000000001 RSI: 00002000000001c0 RDI: 0000000000000005
RBP: 00007ff012411f91 R08: 000020000005ffe4 R09: 000000000000001c
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007ff0125e6038 R14: 00007ff0125e5fa0 R15: 00007ff01270fa28
Showing all locks held in the system:
1 lock held by pool_workqueue_/3:
#0: ffffffff8df42d78 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock kernel/rcu/tree_exp.h:343 [inline]
#0: ffffffff8df42d78 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x3b9/0x730 kernel/rcu/tree_exp.h:957
3 locks held by kworker/u8:1/13:
#0: ffff88801a069948 ((wq_completion)events_unbound#2){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3238 [inline]
#0: ffff88801a069948 ((wq_completion)events_unbound#2){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x17b0 kernel/workqueue.c:3346
#1: ffffc90000127ba0 ((linkwatch_work).work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3239 [inline]
#1: ffffc90000127ba0 ((linkwatch_work).work){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x17b0 kernel/workqueue.c:3346
#2: ffffffff8f2cb148 (rtnl_mutex){+.+.}-{4:4}, at: linkwatch_event+0xe/0x60 net/core/link_watch.c:303
1 lock held by khungtaskd/31:
#0: ffffffff8df3d2e0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
#0: ffffffff8df3d2e0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:867 [inline]
#0: ffffffff8df3d2e0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6775
2 locks held by getty/5592:
#0: ffff88814cf340a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243
#1: ffffc9000332b2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x43e/0x1400 drivers/tty/n_tty.c:2222
1 lock held by syz-executor/5850:
#0: ffffffff8f2cb148 (rtnl_mutex){+.+.}-{4:4}, at: tun_detach drivers/net/tun.c:634 [inline]
#0: ffffffff8f2cb148 (rtnl_mutex){+.+.}-{4:4}, at: tun_chr_close+0x3e/0x1c0 drivers/net/tun.c:3436
2 locks held by kworker/0:3/5887:
#0: ffff88801a055948 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3238 [inline]
#0: ffff88801a055948 ((wq_completion)events){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x17b0 kernel/workqueue.c:3346
#1: ffffc9000444fba0 (free_ipc_work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3239 [inline]
#1: ffffc9000444fba0 (free_ipc_work){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x17b0 kernel/workqueue.c:3346
3 locks held by kworker/0:5/5907:
1 lock held by syz.0.43/6098:
#0: ffffffff8f2cb148 (rtnl_mutex){+.+.}-{4:4}, at: tun_detach drivers/net/tun.c:634 [inline]
#0: ffffffff8f2cb148 (rtnl_mutex){+.+.}-{4:4}, at: tun_chr_close+0x3e/0x1c0 drivers/net/tun.c:3436
1 lock held by syz.2.929/9587:
#0: ffff88807e4040a8 (&ctx->uring_lock){+.+.}-{4:4}, at: io_uring_del_tctx_node+0xf0/0x2c0 io_uring/tctx.c:179
2 locks held by syz.2.929/9588:
1 lock held by syz-executor/9784:
#0: ffffffff8f2cb148 (rtnl_mutex){+.+.}-{4:4}, at: tun_detach drivers/net/tun.c:634 [inline]
#0: ffffffff8f2cb148 (rtnl_mutex){+.+.}-{4:4}, at: tun_chr_close+0x3e/0x1c0 drivers/net/tun.c:3436
=============================================
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 31 Comm: khungtaskd Not tainted syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/02/2025
Call Trace:
dump_stack_lvl+0x189/0x250 lib/dump_stack.c:120
nmi_cpu_backtrace+0x39e/0x3d0 lib/nmi_backtrace.c:113
nmi_trigger_cpumask_backtrace+0x17a/0x300 lib/nmi_backtrace.c:62
trigger_all_cpu_backtrace include/linux/nmi.h:160 [inline]
check_hung_uninterruptible_tasks kernel/hung_task.c:332 [inline]
watchdog+0xf60/0xfa0 kernel/hung_task.c:495
kthread+0x711/0x8a0 kernel/kthread.c:463
ret_from_fork+0x4bc/0x870 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 50 Comm: kworker/u8:3 Not tainted syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/02/2025
Workqueue: events_unbound toggle_allocation_gate
RIP: 0010:preempt_count arch/x86/include/asm/preempt.h:27 [inline]
RIP: 0010:check_kcov_mode kernel/kcov.c:183 [inline]
RIP: 0010:__sanitizer_cov_trace_pc+0x11/0x70 kernel/kcov.c:217
Code: 5b e9 93 86 5a 00 cc cc cc 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 48 8b 04 24 65 48 8b 0c 25 08 20 6e 92 <65> 8b 15 18 1c ae 10 81 e2 00 01 ff 00 74 11 81 fa 00 01 00 00 75
RSP: 0018:ffffc90000bb7620 EFLAGS: 00000246
RAX: ffffffff820b5898 RBX: ffff88801a063aa8 RCX: ffff888021ab9e40
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 1ffff1100340c4aa R08: ffffea00000868c7 R09: 1ffffd4000010d18
R10: dffffc0000000000 R11: fffff94000010d19 R12: 000ffffffffff000
R13: dffffc0000000000 R14: 0000000000000000 R15: 000000001a063067
FS: 0000000000000000(0000) GS:ffff88812623e000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00005631cf931950 CR3: 000000000dd38000 CR4: 00000000003526f0
DR0: 000000000000004b DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400
Call Trace:
walk_to_pmd+0x2b8/0x460 mm/memory.c:2213
__get_locked_pte+0x27/0xd0 mm/memory.c:2220
get_locked_pte include/linux/mm.h:2815 [inline]
__text_poke+0x2e6/0xa10 arch/x86/kernel/alternative.c:2527
text_poke arch/x86/kernel/alternative.c:2612 [inline]
smp_text_poke_batch_finish+0x90a/0x1130 arch/x86/kernel/alternative.c:2945
arch_jump_label_transform_apply+0x1c/0x30 arch/x86/kernel/jump_label.c:146
static_key_disable_cpuslocked+0xc5/0x1b0 kernel/jump_label.c:240
static_key_disable+0x1a/0x20 kernel/jump_label.c:248
toggle_allocation_gate+0x1a1/0x240 mm/kfence/core.c:857
process_one_work kernel/workqueue.c:3263 [inline]
process_scheduled_works+0xae1/0x17b0 kernel/workqueue.c:3346
worker_thread+0x8a0/0xda0 kernel/workqueue.c:3427
kthread+0x711/0x8a0 kernel/kthread.c:463
ret_from_fork+0x4bc/0x870 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245