INFO: task syz.4.790:6615 blocked for more than 143 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.4.790 state:D stack:23280 pid: 6615 ppid: 4194 flags:0x00004006
Call Trace:
context_switch kernel/sched/core.c:5049 [inline]
__schedule+0x11c3/0x4350 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+0x34/0xe30 kernel/events/core.c:5133
put_event kernel/events/core.c:5258 [inline]
perf_event_release_kernel+0x7c4/0x850 kernel/events/core.c:5383
perf_release+0x37/0x40 kernel/events/core.c:5393
__fput+0x212/0x8c0 fs/file_table.c:311
task_work_run+0x125/0x1a0 kernel/task_work.c:188
get_signal+0x123e/0x12e0 kernel/signal.c:2673
arch_do_signal_or_restart+0xe6/0x12a0 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: 0033:0x7fd6e4a2be59
RSP: 002b:00007fd6e2c83fd8 EFLAGS: 00000206 ORIG_RAX: 0000000000000038
RAX: fffffffffffffffc RBX: 00007fd6e4cb3fa0 RCX: 00007fd6e4a2be59
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 00000000640c7000
RBP: 00007fd6e4ac1e6f R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000206 R12: 0000000000000000
R13: 00007fd6e4cb4038 R14: 00007fd6e4cb3fa0 R15: 00007fff02e06118
Showing all locks held in the system:
1 lock held by khungtaskd/27:
#0: ffffffff8c31ef20 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire+0x0/0x30
2 locks held by getty/3945:
#0: ffff88802bfee098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x21/0x70 drivers/tty/tty_ldisc.c:252
#1: ffffc900021ce2e8 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x594/0x1a50 drivers/tty/n_tty.c:2158
3 locks held by kworker/0:15/6061:
#0: ffff888016c70938 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x75c/0xff0 kernel/workqueue.c:-1
#1: ffffc9000321fd00 ((work_completion)(&pwq->unbound_release_work)){+.+.}-{0:0}, at: process_one_work+0x79e/0xff0 kernel/workqueue.c:2285
#2: ffffffff8c3239a8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:322 [inline]
#2: ffffffff8c3239a8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x3a5/0x750 kernel/rcu/tree_exp.h:845
4 locks held by kworker/u4:8/6980:
#0: ffff888016dcd938 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work+0x75c/0xff0 kernel/workqueue.c:-1
#1: ffffc90003b4fd00 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work+0x79e/0xff0 kernel/workqueue.c:2285
#2: ffffffff8d43f210 (pernet_ops_rwsem){++++}-{3:3}, at: cleanup_net+0x148/0xba0 net/core/net_namespace.c:589
#3: ffffffff8c3239a8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:290 [inline]
#3: ffffffff8c3239a8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x2d1/0x750 kernel/rcu/tree_exp.h:845
2 locks held by kworker/1:9/10644:
#0: ffff888016c70938 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x75c/0xff0 kernel/workqueue.c:-1
#1: ffffc900032afd00 ((work_completion)(&pwq->unbound_release_work)){+.+.}-{0:0}, at: process_one_work+0x79e/0xff0 kernel/workqueue.c:2285
3 locks held by kworker/1:10/10646:
#0: ffff888016c70938 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x75c/0xff0 kernel/workqueue.c:-1
#1: ffffc9000346fd00 ((work_completion)(&map->work)){+.+.}-{0:0}, at: process_one_work+0x79e/0xff0 kernel/workqueue.c:2285
#2: ffffffff8c3238b0 (rcu_state.barrier_mutex){+.+.}-{3:3}, at: rcu_barrier+0xa1/0x4c0 kernel/rcu/tree.c:4043
2 locks held by kworker/1:11/10649:
#0: ffff888016c72138 ((wq_completion)rcu_gp){+.+.}-{0:0}, at: process_one_work+0x75c/0xff0 kernel/workqueue.c:-1
#1: ffffc900034bfd00 ((work_completion)(&rew.rew_work)){+.+.}-{0:0}, at: process_one_work+0x79e/0xff0 kernel/workqueue.c:2285
1 lock held by syz.2.2706/11762:
#0: ffffffff8c36c5e8 (event_mutex){+.+.}-{3:3}, at: perf_trace_destroy+0x2a/0x140 kernel/trace/trace_event_perf.c:239
1 lock held by syz.5.2714/11781:
#0: ffffffff8c36c5e8 (event_mutex){+.+.}-{3:3}, at: perf_trace_destroy+0x2a/0x140 kernel/trace/trace_event_perf.c:239
2 locks held by syz.0.2713/11783:
#0: ffffffff96340918 (&pmus_srcu){....}-{0:0}, at: rcu_lock_acquire+0x9/0x30 include/linux/rcupdate.h:313
#1: ffffffff8c36c5e8 (event_mutex){+.+.}-{3:3}, at: perf_trace_init+0x4c/0x2d0 kernel/trace/trace_event_perf.c:221
1 lock held by syz.2.2706/11782:
#0: ffffffff8c36c5e8 (event_mutex){+.+.}-{3:3}, at: perf_trace_destroy+0x2a/0x140 kernel/trace/trace_event_perf.c:239
=============================================
NMI backtrace for cpu 1
CPU: 1 PID: 27 Comm: khungtaskd Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/09/2026
Call Trace:
dump_stack_lvl+0x188/0x250 lib/dump_stack.c:106
nmi_cpu_backtrace+0x3a2/0x3d0 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+0xe1b/0xe60 kernel/hung_task.c:369
kthread+0x42e/0x520 kernel/kthread.c:334
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 PID: 3542 Comm: syslogd Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/09/2026
RIP: 0010:__syscall_enter_from_user_work kernel/entry/common.c:95 [inline]
RIP: 0010:syscall_enter_from_user_mode+0x2e/0x70 kernel/entry/common.c:114
Code: 89 f3 49 89 fe 48 8b 7c 24 10 e8 3d f6 ff ff eb 31 eb 35 e8 24 f9 bf f7 e8 1f f7 bf f7 fb 65 48 8b 05 06 4e 43 76 48 8b 70 08 <40> f6 c6 3f 74 0b 4c 89 f7 5b 41 5e e9 f1 fb a7 f7 48 89 d8 5b 41
RSP: 0018:ffffc900021e7f08 EFLAGS: 00000286
RAX: ffff88807ef73b80 RBX: 0000000000000000 RCX: 511562acf3e81a00
RDX: dffffc0000000000 RSI: 0000000000000000 RDI: ffffffff8a7a2a40
RBP: ffffc900021e7f48 R08: ffff8880b903b30b R09: 1ffff11017207661
R10: dffffc0000000000 R11: ffffed1017207662 R12: 0000000000000000
R13: 0000000000000000 R14: ffffc900021e7f58 R15: 0000000000000000
FS: 00007f6bfa612c80(0000) GS:ffff8880b9000000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f0aa044f158 CR3: 000000007e8ee000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000200000000300 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000600
Call Trace:
do_syscall_64+0x24/0xa0 arch/x86/entry/common.c:76
entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7f6bfa762407
Code: 48 89 fa 4c 89 df e8 38 aa 00 00 8b 93 08 03 00 00 59 5e 48 83 f8 fc 74 1a 5b c3 0f 1f 84 00 00 00 00 00 48 8b 44 24 10 0f 05 <5b> c3 0f 1f 80 00 00 00 00 83 e2 39 83 fa 08 75 de e8 23 ff ff ff
RSP: 002b:00007ffc77653040 EFLAGS: 00000202 ORIG_RAX: 0000000000000000
RAX: ffffffffffffffda RBX: 00007f6bfa612c80 RCX: 00007f6bfa762407
RDX: 00000000000000ff RSI: 0000560ed38d0950 RDI: 0000000000000000
RBP: 0000560ed38d0910 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000202 R12: 0000560ed38d099c
R13: 0000000000000000 R14: 0000560ed38d0950 R15: 0000560eb94f2d98