INFO: task kworker/0:3:5886 blocked for more than 143 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:kworker/0:3 state:D stack:25128 pid:5886 tgid:5886 ppid:2 task_flags:0x4208060 flags:0x00004000
Workqueue: events p9_write_work
Call Trace:
context_switch kernel/sched/core.c:5357 [inline]
__schedule+0x1190/0x5de0 kernel/sched/core.c:6961
__schedule_loop kernel/sched/core.c:7043 [inline]
schedule+0xe7/0x3a0 kernel/sched/core.c:7058
schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7115
__mutex_lock_common kernel/locking/mutex.c:676 [inline]
__mutex_lock+0x81b/0x1060 kernel/locking/mutex.c:760
anon_pipe_write+0x15d/0x1a90 fs/pipe.c:458
__kernel_write_iter+0x317/0xb10 fs/read_write.c:619
__kernel_write fs/read_write.c:639 [inline]
kernel_write fs/read_write.c:660 [inline]
kernel_write+0x1f4/0x6c0 fs/read_write.c:650
p9_fd_write net/9p/trans_fd.c:434 [inline]
p9_write_work+0x258/0xc10 net/9p/trans_fd.c:485
process_one_work+0x9cf/0x1b70 kernel/workqueue.c:3236
process_scheduled_works kernel/workqueue.c:3319 [inline]
worker_thread+0x6c8/0xf10 kernel/workqueue.c:3400
kthread+0x3c5/0x780 kernel/kthread.c:463
ret_from_fork+0x5d7/0x6f0 arch/x86/kernel/process.c:148
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
Showing all locks held in the system:
3 locks held by kworker/0:0/9:
#0: ffff88801b878d48 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x12a2/0x1b70 kernel/workqueue.c:3211
#1: ffffc900000e7d10 ((work_completion)(&m->wq)){+.+.}-{0:0}, at: process_one_work+0x929/0x1b70 kernel/workqueue.c:3212
#2: ffff88805bbde068 (&pipe->mutex){+.+.}-{4:4}, at: anon_pipe_write+0x15d/0x1a90 fs/pipe.c:458
3 locks held by kworker/0:1/10:
#0: ffff88801b878d48 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x12a2/0x1b70 kernel/workqueue.c:3211
#1: ffffc900000f7d10 ((work_completion)(&m->wq)){+.+.}-{0:0}, at: process_one_work+0x929/0x1b70 kernel/workqueue.c:3212
#2: ffff888071621c68 (&pipe->mutex){+.+.}-{4:4}, at: anon_pipe_write+0x15d/0x1a90 fs/pipe.c:458
1 lock held by khungtaskd/31:
#0: ffffffff8e5c1220 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
#0: ffffffff8e5c1220 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline]
#0: ffffffff8e5c1220 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x36/0x1c0 kernel/locking/lockdep.c:6775
3 locks held by kworker/1:1/44:
#0: ffff88801b878d48 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x12a2/0x1b70 kernel/workqueue.c:3211
#1: ffffc90000b47d10 ((work_completion)(&m->wq)){+.+.}-{0:0}, at: process_one_work+0x929/0x1b70 kernel/workqueue.c:3212
#2: ffff8880743c6c68 (&pipe->mutex){+.+.}-{4:4}, at: anon_pipe_write+0x15d/0x1a90 fs/pipe.c:458
4 locks held by kworker/u8:4/59:
3 locks held by kworker/1:2/913:
#0: ffff88801b878d48 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x12a2/0x1b70 kernel/workqueue.c:3211
#1: ffffc900045b7d10 ((work_completion)(&m->wq)){+.+.}-{0:0}, at: process_one_work+0x929/0x1b70 kernel/workqueue.c:3212
#2: ffff8880337f9468 (&pipe->mutex){+.+.}-{4:4}, at: anon_pipe_write+0x15d/0x1a90 fs/pipe.c:458
2 locks held by getty/5604:
#0: ffff88814cdaa0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x24/0x80 drivers/tty/tty_ldisc.c:243
#1: ffffc9000332b2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x41b/0x14f0 drivers/tty/n_tty.c:2222
3 locks held by kworker/1:3/5885:
#0: ffff88801b878d48 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x12a2/0x1b70 kernel/workqueue.c:3211
#1: ffffc90003657d10 ((work_completion)(&m->wq)){+.+.}-{0:0}, at: process_one_work+0x929/0x1b70 kernel/workqueue.c:3212
#2: ffff88807aec2068 (&pipe->mutex){+.+.}-{4:4}, at: anon_pipe_write+0x15d/0x1a90 fs/pipe.c:458
3 locks held by kworker/0:3/5886:
#0: ffff88801b878d48 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x12a2/0x1b70 kernel/workqueue.c:3211
#1: ffffc90003667d10 ((work_completion)(&m->wq)){+.+.}-{0:0}, at: process_one_work+0x929/0x1b70 kernel/workqueue.c:3212
#2: ffff888025557068 (&pipe->mutex){+.+.}-{4:4}, at: anon_pipe_write+0x15d/0x1a90 fs/pipe.c:458
3 locks held by kworker/0:4/6006:
#0: ffff88801b878d48 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x12a2/0x1b70 kernel/workqueue.c:3211
#1: ffffc90003b27d10 ((work_completion)(&m->wq)){+.+.}-{0:0}, at: process_one_work+0x929/0x1b70 kernel/workqueue.c:3212
#2: ffff88807ae6c868 (&pipe->mutex){+.+.}-{4:4}, at: anon_pipe_write+0x15d/0x1a90 fs/pipe.c:458
2 locks held by syz.0.16/6443:
#0: ffff888025557068 (&pipe->mutex){+.+.}-{4:4}, at: anon_pipe_write+0x15d/0x1a90 fs/pipe.c:458
#1: ffff88805d7782e8 (mapping.invalidate_lock#3){.+.+}-{4:4}, at: filemap_invalidate_lock_shared include/linux/fs.h:934 [inline]
#1: ffff88805d7782e8 (mapping.invalidate_lock#3){.+.+}-{4:4}, at: filemap_fault+0x61d/0x2930 mm/filemap.c:3452
2 locks held by syz.1.17/6472:
#0: ffff88807ae6c868 (&pipe->mutex){+.+.}-{4:4}, at: anon_pipe_write+0x15d/0x1a90 fs/pipe.c:458
#1: ffff88805d778958 (mapping.invalidate_lock#3){.+.+}-{4:4}, at: filemap_invalidate_lock_shared include/linux/fs.h:934 [inline]
#1: ffff88805d778958 (mapping.invalidate_lock#3){.+.+}-{4:4}, at: filemap_fault+0x61d/0x2930 mm/filemap.c:3452
2 locks held by syz.2.18/6496:
#0: ffff8880337f9468 (&pipe->mutex){+.+.}-{4:4}, at: anon_pipe_write+0x15d/0x1a90 fs/pipe.c:458
#1: ffff88805d7e82e8 (mapping.invalidate_lock#3){.+.+}-{4:4}, at: filemap_invalidate_lock_shared include/linux/fs.h:934 [inline]
#1: ffff88805d7e82e8 (mapping.invalidate_lock#3){.+.+}-{4:4}, at: filemap_fault+0x61d/0x2930 mm/filemap.c:3452
3 locks held by kworker/1:4/6498:
#0: ffff88801b878d48 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x12a2/0x1b70 kernel/workqueue.c:3211
#1: ffffc90002fc7d10 ((work_completion)(&m->wq)){+.+.}-{0:0}, at: process_one_work+0x929/0x1b70 kernel/workqueue.c:3212
#2: ffff888073d5c868 (&pipe->mutex){+.+.}-{4:4}, at: anon_pipe_write+0x15d/0x1a90 fs/pipe.c:458
2 locks held by syz.3.19/6524:
#0: ffff8880743c6c68 (&pipe->mutex){+.+.}-{4:4}, at: anon_pipe_write+0x15d/0x1a90 fs/pipe.c:458
#1: ffff88805d7e8958 (mapping.invalidate_lock#3){.+.+}-{4:4}, at: filemap_invalidate_lock_shared include/linux/fs.h:934 [inline]
#1: ffff88805d7e8958 (mapping.invalidate_lock#3){.+.+}-{4:4}, at: filemap_fault+0x61d/0x2930 mm/filemap.c:3452
2 locks held by syz.4.20/6557:
#0: ffff88807aec2068 (&pipe->mutex){+.+.}-{4:4}, at: anon_pipe_write+0x15d/0x1a90 fs/pipe.c:458
#1: ffff88805d7e8fc8 (mapping.invalidate_lock#3){.+.+}-{4:4}, at: filemap_invalidate_lock_shared include/linux/fs.h:934 [inline]
#1: ffff88805d7e8fc8 (mapping.invalidate_lock#3){.+.+}-{4:4}, at: filemap_fault+0x61d/0x2930 mm/filemap.c:3452
3 locks held by kworker/1:6/6558:
#0: ffff88801b878d48 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x12a2/0x1b70 kernel/workqueue.c:3211
#1: ffffc90003777d10 ((work_completion)(&m->wq)){+.+.}-{0:0}, at: process_one_work+0x929/0x1b70 kernel/workqueue.c:3212
#2: ffff88807957a068 (&pipe->mutex){+.+.}-{4:4}, at: anon_pipe_write+0x15d/0x1a90 fs/pipe.c:458
2 locks held by syz.5.21/6587:
#0: ffff888071621c68 (&pipe->mutex){+.+.}-{4:4}, at: anon_pipe_write+0x15d/0x1a90 fs/pipe.c:458
#1: ffff88805d778fc8 (mapping.invalidate_lock#3){.+.+}-{4:4}, at: filemap_invalidate_lock_shared include/linux/fs.h:934 [inline]
#1: ffff88805d778fc8 (mapping.invalidate_lock#3){.+.+}-{4:4}, at: filemap_fault+0x61d/0x2930 mm/filemap.c:3452
3 locks held by kworker/0:7/6588:
#0: ffff88801b878d48 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x12a2/0x1b70 kernel/workqueue.c:3211
#1: ffffc90003ab7d10 ((work_completion)(&m->wq)){+.+.}-{0:0}, at: process_one_work+0x929/0x1b70 kernel/workqueue.c:3212
#2: ffff88807c22d868 (&pipe->mutex){+.+.}-{4:4}, at: anon_pipe_write+0x15d/0x1a90 fs/pipe.c:458
2 locks held by syz.6.22/6617:
#0: ffff88807957a068 (&pipe->mutex){+.+.}-{4:4}, at: anon_pipe_write+0x15d/0x1a90 fs/pipe.c:458
#1: ffff88805d7e9638 (mapping.invalidate_lock#3){.+.+}-{4:4}, at: filemap_invalidate_lock_shared include/linux/fs.h:934 [inline]
#1: ffff88805d7e9638 (mapping.invalidate_lock#3){.+.+}-{4:4}, at: filemap_fault+0x61d/0x2930 mm/filemap.c:3452
2 locks held by syz.7.23/6652:
#0: ffff888073d5c868 (&pipe->mutex){+.+.}-{4:4}, at: anon_pipe_write+0x15d/0x1a90 fs/pipe.c:458
#1: ffff88805d7e9ca8 (mapping.invalidate_lock#3){.+.+}-{4:4}, at: filemap_invalidate_lock_shared include/linux/fs.h:934 [inline]
#1: ffff88805d7e9ca8 (mapping.invalidate_lock#3){.+.+}-{4:4}, at: filemap_fault+0x61d/0x2930 mm/filemap.c:3452
2 locks held by syz.8.24/6684:
#0: ffff88807c22d868 (&pipe->mutex){+.+.}-{4:4}, at: anon_pipe_write+0x15d/0x1a90 fs/pipe.c:458
#1: ffff88805d779638 (mapping.invalidate_lock#3){.+.+}-{4:4}, at: filemap_invalidate_lock_shared include/linux/fs.h:934 [inline]
#1: ffff88805d779638 (mapping.invalidate_lock#3){.+.+}-{4:4}, at: filemap_fault+0x61d/0x2930 mm/filemap.c:3452
2 locks held by syz.9.25/6715:
#0: ffff88805bbde068 (&pipe->mutex){+.+.}-{4:4}, at: anon_pipe_write+0x15d/0x1a90 fs/pipe.c:458
#1: ffff88805d779ca8 (mapping.invalidate_lock#3){.+.+}-{4:4}, at: filemap_invalidate_lock_shared include/linux/fs.h:934 [inline]
#1: ffff88805d779ca8 (mapping.invalidate_lock#3){.+.+}-{4:4}, at: filemap_fault+0x61d/0x2930 mm/filemap.c:3452
=============================================
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 31 Comm: khungtaskd Not tainted syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025
Call Trace:
__dump_stack lib/dump_stack.c:94 [inline]
dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:120
nmi_cpu_backtrace+0x27b/0x390 lib/nmi_backtrace.c:113
nmi_trigger_cpumask_backtrace+0x29c/0x300 lib/nmi_backtrace.c:62
trigger_all_cpu_backtrace include/linux/nmi.h:160 [inline]
check_hung_uninterruptible_tasks kernel/hung_task.c:328 [inline]
watchdog+0xf0e/0x1260 kernel/hung_task.c:491
kthread+0x3c5/0x780 kernel/kthread.c:463
ret_from_fork+0x5d7/0x6f0 arch/x86/kernel/process.c:148
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 0 Comm: swapper/1 Not tainted syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025
RIP: 0010:pv_native_safe_halt+0xf/0x20 arch/x86/kernel/paravirt.c:82
Code: 4c 62 02 c3 cc cc cc cc 0f 1f 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 66 90 0f 00 2d d3 52 16 00 fb f4 4c 09 03 00 66 2e 0f 1f 84 00 00 00 00 00 66 90 90 90 90 90 90
RSP: 0018:ffffc90000197df8 EFLAGS: 000002c2
RAX: 000000000019548b RBX: 0000000000000001 RCX: ffffffff8b93bc29
RDX: 0000000000000000 RSI: ffffffff8de50220 RDI: ffffffff8c162900
RBP: ffffed1003cdf488 R08: 0000000000000001 R09: ffffed10170a6655
R10: ffff8880b85332ab R11: 0000000000000000 R12: 0000000000000001
R13: ffff88801e6fa440 R14: ffffffff90ab4c90 R15: 0000000000000000
FS: 0000000000000000(0000) GS:ffff8881247b9000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055555b5eb5c8 CR3: 000000000e380000 CR4: 00000000003526f0
Call Trace:
arch_safe_halt arch/x86/include/asm/paravirt.h:107 [inline]
default_idle+0x13/0x20 arch/x86/kernel/process.c:757
default_idle_call+0x6d/0xb0 kernel/sched/idle.c:122
cpuidle_idle_call kernel/sched/idle.c:190 [inline]
do_idle+0x391/0x510 kernel/sched/idle.c:330
cpu_startup_entry+0x4f/0x60 kernel/sched/idle.c:428
start_secondary+0x21d/0x2b0 arch/x86/kernel/smpboot.c:315
common_startup_64+0x13e/0x148