INFO: task kworker/0:1:10 blocked for more than 122 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:kworker/0:1     state:D stack:0     pid:10    tgid:10    ppid:2      flags:0x00004000
Workqueue: events p9_write_work
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5343 [inline]
 __schedule+0xdb5/0x17a0 kernel/sched/core.c:6723
 __schedule_loop kernel/sched/core.c:6800 [inline]
 schedule+0xc6/0x240 kernel/sched/core.c:6815
 schedule_preempt_disabled+0x14/0x30 kernel/sched/core.c:6872
 __mutex_lock_common kernel/locking/mutex.c:684 [inline]
 __mutex_lock+0x755/0x10d0 kernel/locking/mutex.c:752
 __mutex_lock_slowpath+0xe/0x20 kernel/locking/mutex.c:1040
 mutex_lock+0xd9/0xf0 kernel/locking/mutex.c:286
 pipe_write+0x131/0x1850 fs/pipe.c:455
 __kernel_write_iter+0x395/0x830 fs/read_write.c:616
 __kernel_write fs/read_write.c:636 [inline]
 kernel_write+0x2b2/0x640 fs/read_write.c:657
 p9_fd_write net/9p/trans_fd.c:433 [inline]
 p9_write_work+0x54e/0xd30 net/9p/trans_fd.c:484
 process_one_work kernel/workqueue.c:3229 [inline]
 process_scheduled_works+0x7d2/0x1020 kernel/workqueue.c:3310
 worker_thread+0x99f/0xd90 kernel/workqueue.c:3391
 kthread+0x2ca/0x370 kernel/kthread.c:389
 ret_from_fork+0x64/0xa0 arch/x86/kernel/process.c:152
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
 </TASK>
INFO: task kworker/1:3:488 blocked for more than 123 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:kworker/1:3     state:D stack:0     pid:488   tgid:488   ppid:2      flags:0x00004000
Workqueue: events p9_write_work
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5343 [inline]
 __schedule+0xdb5/0x17a0 kernel/sched/core.c:6723
 __schedule_loop kernel/sched/core.c:6800 [inline]
 schedule+0xc6/0x240 kernel/sched/core.c:6815
 schedule_preempt_disabled+0x14/0x30 kernel/sched/core.c:6872
 __mutex_lock_common kernel/locking/mutex.c:684 [inline]
 __mutex_lock+0x755/0x10d0 kernel/locking/mutex.c:752
 __mutex_lock_slowpath+0xe/0x20 kernel/locking/mutex.c:1040
 mutex_lock+0xd9/0xf0 kernel/locking/mutex.c:286
 pipe_write+0x131/0x1850 fs/pipe.c:455
 __kernel_write_iter+0x395/0x830 fs/read_write.c:616
 __kernel_write fs/read_write.c:636 [inline]
 kernel_write+0x2b2/0x640 fs/read_write.c:657
 p9_fd_write net/9p/trans_fd.c:433 [inline]
 p9_write_work+0x54e/0xd30 net/9p/trans_fd.c:484
 process_one_work kernel/workqueue.c:3229 [inline]
 process_scheduled_works+0x7d2/0x1020 kernel/workqueue.c:3310
 worker_thread+0x99f/0xd90 kernel/workqueue.c:3391
 kthread+0x2ca/0x370 kernel/kthread.c:389
 ret_from_fork+0x64/0xa0 arch/x86/kernel/process.c:152
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
 </TASK>
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 37 Comm: khungtaskd Not tainted syzkaller #0 dcc8d9e88d44daac2ed081f046b334c09506d439
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025
Call Trace:
 <TASK>
 __dump_stack+0x21/0x30 lib/dump_stack.c:94
 dump_stack_lvl+0x10c/0x190 lib/dump_stack.c:120
 dump_stack+0x19/0x20 lib/dump_stack.c:129
 nmi_cpu_backtrace+0x2bf/0x2d0 lib/nmi_backtrace.c:113
 nmi_trigger_cpumask_backtrace+0x142/0x2c0 lib/nmi_backtrace.c:62
 arch_trigger_cpumask_backtrace+0x14/0x20 arch/x86/kernel/apic/hw_nmi.c:41
 trigger_all_cpu_backtrace include/linux/nmi.h:158 [inline]
 check_hung_uninterruptible_tasks kernel/hung_task.c:223 [inline]
 watchdog+0xbd4/0xc20 kernel/hung_task.c:379
 kthread+0x2ca/0x370 kernel/kthread.c:389
 ret_from_fork+0x64/0xa0 arch/x86/kernel/process.c:152
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
 </TASK>
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 0 Comm: swapper/0 Not tainted syzkaller #0 dcc8d9e88d44daac2ed081f046b334c09506d439
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025
RIP: 0010:pv_native_safe_halt+0x17/0x20 arch/x86/kernel/paravirt.c:106
Code: cc cc cc b8 16 64 c2 3d 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 66 90 0f 00 2d 13 a2 47 00 f3 0f 1e fa 55 48 89 e5 fb f4 <5d> e9 c3 f6 05 00 cc cc cc b8 00 00 00 00 90 90 90 90 90 90 90 90
RSP: 0018:ffffffff86c07da0 EFLAGS: 000002c2
RAX: ffff8881f6e00000 RBX: ffffffff86c15540 RCX: ffffffff853fae8e
RDX: 0000000000000001 RSI: 0000000000000004 RDI: 000000000003a41c
RBP: ffffffff86c07da0 R08: ffff8881f6e39633 R09: 1ffff1103edc72c6
R10: dffffc0000000000 R11: ffffed103edc72c7 R12: 1ffffffff0d82aa8
R13: 0000000000000000 R14: 0000000000000000 R15: ffffffff876371e8
FS:  0000000000000000(0000) GS:ffff8881f6e00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00005596feffb808 CR3: 00000001284f4000 CR4: 00000000003526b0
Call Trace:
 <TASK>
 arch_safe_halt arch/x86/include/asm/paravirt.h:112 [inline]
 default_idle+0x17/0x30 arch/x86/kernel/process.c:753
 arch_cpu_idle+0xd/0x20 arch/x86/kernel/process.c:790
 default_idle_call+0x3f/0x80 kernel/sched/idle.c:117
 cpuidle_idle_call kernel/sched/idle.c:185 [inline]
 do_idle+0x1a0/0x470 kernel/sched/idle.c:326
 cpu_startup_entry+0x48/0x70 kernel/sched/idle.c:424
 rest_init+0x10b/0x130 init/main.c:747
 start_kernel+0x460/0x4bb init/main.c:1105
 x86_64_start_reservations+0x2e/0x30 arch/x86/kernel/head64.c:507
 x86_64_start_kernel+0x6a/0x7b arch/x86/kernel/head64.c:488
 common_startup_64+0x13b/0x157
 </TASK>