INFO: task rcu_tasks_kthre:11 blocked for more than 143 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:rcu_tasks_kthre state:D stack:27200 pid: 11 ppid: 2 flags:0x00004000
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
schedule_timeout+0xbd/0x2d0 kernel/time/timer.c:2093
do_wait_for_common+0x295/0x460 kernel/sched/completion.c:85
__wait_for_common kernel/sched/completion.c:106 [inline]
wait_for_common kernel/sched/completion.c:117 [inline]
wait_for_completion+0x48/0x60 kernel/sched/completion.c:138
__synchronize_srcu+0x2b5/0x350 kernel/rcu/srcutree.c:930
rcu_tasks_wait_gp+0x43b/0x8e0 kernel/rcu/tasks.h:327
rcu_tasks_kthread+0x2c1/0x640 kernel/rcu/tasks.h:226
kthread+0x42e/0x520 kernel/kthread.c:334
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287
Showing all locks held in the system:
3 locks held by kworker/1:1/23:
1 lock held by khungtaskd/27:
#0: ffffffff8d11efa0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire+0x0/0x30
2 locks held by getty/3944:
#0: ffff88802cb5c098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x21/0x70 drivers/tty/tty_ldisc.c:252
#1: ffffc900026562e8 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x594/0x1a50 drivers/tty/n_tty.c:2158
2 locks held by kworker/0:17/14864:
#0: ffff888017872138 ((wq_completion)rcu_gp){+.+.}-{0:0}, at: process_one_work+0x75c/0xff0 kernel/workqueue.c:-1
#1: ffffc900034efd00 ((work_completion)(&rew.rew_work)){+.+.}-{0:0}, at: process_one_work+0x79e/0xff0 kernel/workqueue.c:2285
3 locks held by kworker/0:0/29717:
#0: ffff888017870938 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x75c/0xff0 kernel/workqueue.c:-1
#1: ffffc900033dfd00 ((work_completion)(&map->work)){+.+.}-{0:0}, at: process_one_work+0x79e/0xff0 kernel/workqueue.c:2285
#2: ffffffff8d123a28 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:322 [inline]
#2: ffffffff8d123a28 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x3a5/0x750 kernel/rcu/tree_exp.h:845
3 locks held by kworker/0:2/416:
#0: ffff888017870938 ((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: ffffffff8d123930 (rcu_state.barrier_mutex){+.+.}-{3:3}, at: rcu_barrier+0xa1/0x4c0 kernel/rcu/tree.c:4043
3 locks held by kworker/0:10/1489:
#0: ffff888017870938 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x75c/0xff0 kernel/workqueue.c:-1
#1: ffffc9000316fd00 ((work_completion)(&map->work)){+.+.}-{0:0}, at: process_one_work+0x79e/0xff0 kernel/workqueue.c:2285
#2: ffffffff8d123930 (rcu_state.barrier_mutex){+.+.}-{3:3}, at: rcu_barrier+0xa1/0x4c0 kernel/rcu/tree.c:4043
3 locks held by kworker/1:3/1762:
2 locks held by syz.2.9685/6323:
3 locks held by syz.7.9689/6331:
2 locks held by syz.1.9705/6374:
2 locks held by syz.2.9719/6418:
2 locks held by syz.7.9724/6430:
1 lock held by syz.1.9739/6485:
1 lock held by syz.7.9744/6492:
#0: ffffffff8d16c808 (event_mutex){+.+.}-{3:3}, at: perf_trace_destroy+0x2a/0x140 kernel/trace/trace_event_perf.c:239
2 locks held by syz.4.9746/6494:
#0: ffffffff8d16c808 (event_mutex){+.+.}-{3:3}, at: perf_trace_destroy+0x2a/0x140 kernel/trace/trace_event_perf.c:239
#1: ffffffff8d123a28 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:322 [inline]
#1: ffffffff8d123a28 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x3a5/0x750 kernel/rcu/tree_exp.h:845
1 lock held by syz.2.9747/6499:
#0: ffffffff8e26ca48 (rtnl_mutex){+.+.}-{3:3}, at: tun_detach drivers/net/tun.c:699 [inline]
#0: ffffffff8e26ca48 (rtnl_mutex){+.+.}-{3:3}, at: tun_chr_close+0x3d/0x1b0 drivers/net/tun.c:3454
1 lock held by syz.1.9745/6515:
#0: ffff88806fda3e10 (&sb->s_type->i_mutex_key#11){+.+.}-{3:3}, at: inode_lock include/linux/fs.h:793 [inline]
#0: ffff88806fda3e10 (&sb->s_type->i_mutex_key#11){+.+.}-{3:3}, at: __sock_release net/socket.c:650 [inline]
#0: ffff88806fda3e10 (&sb->s_type->i_mutex_key#11){+.+.}-{3:3}, at: sock_close+0x82/0x210 net/socket.c:1346
=============================================
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 10/07/2026
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 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 PID: 1762 Comm: kworker/1:3 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/07/2026
Workqueue: rcu_gp process_srcu
RIP: 0010:__mutex_lock_common+0x101/0x2400 kernel/locking/mutex.c:575
Code: c0 48 c7 c0 80 df 14 97 48 c1 e8 03 42 0f b6 04 28 84 c0 0f 85 50 1c 00 00 4c 8d b4 24 e0 00 00 00 83 3d 61 d8 42 0d 00 75 29 <48> 8d 7b 60 48 89 f8 48 c1 e8 03 42 80 3c 28 00 74 05 e8 88 6e ec
RSP: 0018:ffffc900033ef9a0 EFLAGS: 00000246
RAX: 0000000000000004 RBX: ffffffff8d11f9f8 RCX: ffffffff9714df03
RDX: ffff888064e13b80 RSI: ffffffff8a2b3e00 RDI: ffffffff8a7a5100
RBP: ffffc900033efb38 R08: ffffffff81649edf R09: 0000000000000000
R10: dffffc0000000000 R11: fffffbfff1cda646 R12: 0000000000000000
R13: dffffc0000000000 R14: ffffc900033efa80 R15: 0000000000000000
FS: 0000000000000000(0000) GS:ffff8880b8f00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fbbeed71158 CR3: 0000000021ad2000 CR4: 00000000003506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000600
Call Trace:
__mutex_lock kernel/locking/mutex.c:729 [inline]
mutex_lock_nested+0x17/0x20 kernel/locking/mutex.c:743
srcu_advance_state kernel/rcu/srcutree.c:1177 [inline]
process_srcu+0x2f/0xca0 kernel/rcu/srcutree.c:1325
process_one_work+0x867/0xff0 kernel/workqueue.c:2310
worker_thread+0xad7/0x12a0 kernel/workqueue.c:2457
kthread+0x42e/0x520 kernel/kthread.c:334
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287