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:27408 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:
1 lock held by khungtaskd/27:
#0: ffffffff8d11efa0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire+0x0/0x30
4 locks held by kworker/u4:2/155:
3 locks held by kworker/0:2/1109:
1 lock held by dhcpcd/3854:
#0: ffffffff8e26bd48 (rtnl_mutex){+.+.}-{3:3}, at: devinet_ioctl+0x256/0x1ba0 net/ipv4/devinet.c:1076
2 locks held by getty/3951:
#0: ffff88814d00b098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x21/0x70 drivers/tty/tty_ldisc.c:252
#1: ffffc90002d032e8 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x594/0x1a50 drivers/tty/n_tty.c:2158
3 locks held by kworker/0:4/4280:
#0: ffff888017870938 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x75c/0xff0 kernel/workqueue.c:-1
#1: ffffc9000310fd00 ((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/0:25/9645:
#0: ffff888017870938 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x75c/0xff0 kernel/workqueue.c:-1
#1: ffffc9000338fd00 ((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:290 [inline]
#2: ffffffff8d123a28 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x2d1/0x750 kernel/rcu/tree_exp.h:845
3 locks held by kworker/0:36/9660:
#0: ffff888017870938 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x75c/0xff0 kernel/workqueue.c:-1
#1: ffffc900034bfd00 (deferred_process_work){+.+.}-{0:0}, at: process_one_work+0x79e/0xff0 kernel/workqueue.c:2285
#2: ffffffff8e26bd48 (rtnl_mutex){+.+.}-{3:3}, at: switchdev_deferred_process_work+0xa/0x20 net/switchdev/switchdev.c:74
2 locks held by kworker/0:40/9664:
#0: ffff888017872138 ((wq_completion)rcu_gp){+.+.}-{0:0}, at: process_one_work+0x75c/0xff0 kernel/workqueue.c:-1
#1: ffffc900034ffd00 ((work_completion)(&rew.rew_work)){+.+.}-{0:0}, at: process_one_work+0x79e/0xff0 kernel/workqueue.c:2285
3 locks held by kworker/u4:8/10268:
#0: ffff888017879138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work+0x75c/0xff0 kernel/workqueue.c:-1
#1: ffffc9000385fd00 ((linkwatch_work).work){+.+.}-{0:0}, at: process_one_work+0x79e/0xff0 kernel/workqueue.c:2285
#2: ffffffff8e26bd48 (rtnl_mutex){+.+.}-{3:3}, at: linkwatch_event+0xa/0x50 net/core/link_watch.c:251
1 lock held by syz.3.5971/26720:
#0: ffffffff8d16c808 (event_mutex){+.+.}-{3:3}, at: perf_trace_destroy+0x2a/0x140 kernel/trace/trace_event_perf.c:239
3 locks held by syz.3.5971/26725:
#0: ffffffff8e253fe8 (br_ioctl_mutex){+.+.}-{3:3}, at: br_ioctl_call net/socket.c:1120 [inline]
#0: ffffffff8e253fe8 (br_ioctl_mutex){+.+.}-{3:3}, at: sock_ioctl+0x434/0x700 net/socket.c:1221
#1: ffffffff8e26bd48 (rtnl_mutex){+.+.}-{3:3}, at: br_ioctl_stub+0x1a5/0xbe0 net/bridge/br_ioctl.c:392
#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
=============================================
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 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 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 PID: 9645 Comm: kworker/0:25 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:__queue_work+0x2c5/0xc80 kernel/workqueue.c:1465
Code: 8b 3e 4c 63 34 24 bf 08 00 00 00 44 89 f6 e8 22 3c 2b 00 41 83 fe 07 0f 87 b8 03 00 00 e8 b3 38 2b 00 4e 8d 34 f5 20 38 e6 8b <4c> 89 f0 48 c1 e8 03 80 3c 18 00 74 08 4c 89 f7 e8 96 7d 70 00 4d
RSP: 0018:ffffc9000338fae0 EFLAGS: 00000093
RAX: ffffffff814deaad RBX: dffffc0000000000 RCX: ffff888049be1dc0
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000008
RBP: 0000000000000005 R08: dffffc0000000000 R09: 1ffffffff2208c18
R10: dffffc0000000000 R11: fffffbfff2208c19 R12: 0000000000000008
R13: 0000000000000200 R14: ffffffff8be63820 R15: 000000000003fc00
FS: 0000000000000000(0000) GS:ffff8880b8e00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f8c908082f8 CR3: 000000002065c000 CR4: 00000000003506f0
DR0: 00002000000010c0 DR1: 0000200000000300 DR2: 0000000000000000
DR3: 0000200000000300 DR6: 00000000ffff0ff0 DR7: 0000000000000600
Call Trace:
queue_delayed_work_on+0x12d/0x1f0 kernel/workqueue.c:1715
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