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:27440 pid:   11 ppid:     2 flags:0x00004000
Call Trace:
 <TASK>
 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
 </TASK>

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
2 locks held by getty/3949:
 #0: ffff88802cedf098 (&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
4 locks held by kworker/u4:10/28251:
2 locks held by kworker/u4:12/28255:
2 locks held by syz.7.12421/21795:
2 locks held by syz.9.12424/21810:
2 locks held by syz.7.12429/21839:
2 locks held by syz.4.12448/21948:
2 locks held by dhcpcd-run-hook/22017:

=============================================

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:
 <TASK>
 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
 </TASK>
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 PID: 4176 Comm: syz-executor Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/07/2026
RIP: 0010:iocb_flags include/linux/fs.h:3585 [inline]
RIP: 0010:init_sync_kiocb include/linux/fs.h:2345 [inline]
RIP: 0010:new_sync_read fs/read_write.c:400 [inline]
RIP: 0010:vfs_read+0x3d4/0xd50 fs/read_write.c:485
Code: 04 28 84 c0 0f 85 8e 08 00 00 41 8b 1e 41 89 de 41 c1 ee 06 41 83 e6 10 41 89 dd 41 81 e5 00 40 00 00 89 de 81 e6 00 10 00 00 <31> ff e8 a5 a7 b0 ff 89 5c 24 4c 47 8d 34 ee 81 e3 00 10 00 00 0f
RSP: 0018:ffffc9000302fcc0 EFLAGS: 00000246
RAX: 0000000000000000 RBX: 0000000000000802 RCX: 0000000000000000
RDX: 0000000000000028 RSI: 0000000000000000 RDI: ffffc9000302fdd8
RBP: ffffc9000302fe50 R08: ffffc9000302fdd7 R09: ffffc9000302fdb0
R10: dffffc0000000000 R11: fffff52000605fbb R12: 1ffff92000605fa4
R13: 0000000000000000 R14: 0000000000000000 R15: 1ffff11004d144a5
FS:  0000555570217500(0000) GS:ffff8880b8e00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f98f0267a90 CR3: 0000000072ef4000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000200000000300 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000600
Call Trace:
 <TASK>
 ksys_read+0x153/0x260 fs/read_write.c:623
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7f13d0c2b6d7
Code: 48 89 fa 4c 89 df e8 a8 56 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:00007fffa06e0f70 EFLAGS: 00000202 ORIG_RAX: 0000000000000000
RAX: ffffffffffffffda RBX: 0000555570217500 RCX: 00007f13d0c2b6d7
RDX: 0000000000000004 RSI: 00007fffa06e0fcc RDI: 0000000000000003
RBP: 00007fffa06e1470 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000202 R12: 0000000000000004
R13: 00007fffa06e0fcc R14: 00007fffa06e1060 R15: 0000000000000000
 </TASK>