INFO: task kworker/u8:2:37 blocked for more than 143 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:kworker/u8:2 state:D stack:13360 pid:37 tgid:37 ppid:2 flags:0x00004000
Workqueue: events_unbound netfs_write_collection_worker
Call Trace:
context_switch kernel/sched/core.c:5369 [inline]
__schedule+0x510/0xb30 kernel/sched/core.c:6756
__schedule_loop kernel/sched/core.c:6833 [inline]
schedule+0x25/0x110 kernel/sched/core.c:6848
bit_wait+0xc/0x60 kernel/sched/wait_bit.c:237
__wait_on_bit+0x46/0x150 kernel/sched/wait_bit.c:49
out_of_line_wait_on_bit+0x92/0xb0 kernel/sched/wait_bit.c:64
wait_on_bit include/linux/wait_bit.h:77 [inline]
netfs_retry_writes fs/netfs/write_collect.c:347 [inline]
netfs_collect_write_results fs/netfs/write_collect.c:529 [inline]
netfs_write_collection_worker+0xd0b/0x16e0 fs/netfs/write_collect.c:551
process_one_work+0x22f/0x6b0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x1c2/0x360 kernel/workqueue.c:3391
kthread+0xd6/0x100 kernel/kthread.c:389
ret_from_fork+0x2c/0x50 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
INFO: task syz.3.17:2918 blocked for more than 143 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.3.17 state:D stack:14824 pid:2918 tgid:2916 ppid:2462 flags:0x00000004
Call Trace:
context_switch kernel/sched/core.c:5369 [inline]
__schedule+0x510/0xb30 kernel/sched/core.c:6756
__schedule_loop kernel/sched/core.c:6833 [inline]
schedule+0x25/0x110 kernel/sched/core.c:6848
schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6905
rwsem_down_write_slowpath+0x2bb/0x700 kernel/locking/rwsem.c:1176
__down_write_common kernel/locking/rwsem.c:1304 [inline]
__down_write kernel/locking/rwsem.c:1313 [inline]
down_write+0x86/0x90 kernel/locking/rwsem.c:1578
inode_lock include/linux/fs.h:831 [inline]
vfs_utimes+0x123/0x260 fs/utimes.c:65
do_utimes_path fs/utimes.c:99 [inline]
do_utimes+0xc9/0x130 fs/utimes.c:140
__do_sys_utime fs/utimes.c:221 [inline]
__se_sys_utime fs/utimes.c:210 [inline]
__x64_sys_utime+0x81/0xb0 fs/utimes.c:210
do_syscall_x64 arch/x86/entry/common.c:52 [inline]
do_syscall_64+0x6d/0x170 arch/x86/entry/common.c:83
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f42e3c2eba9
RSP: 002b:00007f42e3a7e038 EFLAGS: 00000246 ORIG_RAX: 0000000000000084
RAX: ffffffffffffffda RBX: 00007f42e3e76090 RCX: 00007f42e3c2eba9
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 00002000000000c0
RBP: 00007f42e3cb1e19 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f42e3e76128 R14: 00007f42e3e76090 R15: 00007ffc75987e88
Showing all locks held in the system:
2 locks held by kworker/u8:0/11:
#0: ffff888100078948 ((wq_completion)events_unbound){....}-{0:0}, at: process_one_work+0x442/0x6b0 kernel/workqueue.c:3204
#1: ffffc90000063e58 ((work_completion)(&rreq->work)){....}-{0:0}, at: process_one_work+0x1ec/0x6b0 kernel/workqueue.c:3205
2 locks held by kworker/u8:1/13:
#0: ffff888100078948 ((wq_completion)events_unbound){....}-{0:0}, at: process_one_work+0x442/0x6b0 kernel/workqueue.c:3204
#1: ffffc90000073e58 ((work_completion)(&rreq->work)){....}-{0:0}, at: process_one_work+0x1ec/0x6b0 kernel/workqueue.c:3205
1 lock held by khungtaskd/30:
#0: ffffffff8277e700 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:337 [inline]
#0: ffffffff8277e700 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline]
#0: ffffffff8277e700 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x36/0x120 kernel/locking/lockdep.c:6744
2 locks held by kworker/u8:2/37:
#0: ffff888100078948 ((wq_completion)events_unbound){....}-{0:0}, at: process_one_work+0x442/0x6b0 kernel/workqueue.c:3204
#1: ffffc9000013fe58 ((work_completion)(&rreq->work)){....}-{0:0}, at: process_one_work+0x1ec/0x6b0 kernel/workqueue.c:3205
2 locks held by kworker/u8:3/67:
#0: ffff888100078948 ((wq_completion)events_unbound){....}-{0:0}, at: process_one_work+0x442/0x6b0 kernel/workqueue.c:3204
#1: ffffc9000019be58 ((work_completion)(&rreq->work)){....}-{0:0}, at: process_one_work+0x1ec/0x6b0 kernel/workqueue.c:3205
2 locks held by kworker/u8:4/123:
#0: ffff888100078948 ((wq_completion)events_unbound){....}-{0:0}, at: process_one_work+0x442/0x6b0 kernel/workqueue.c:3204
#1: ffffc9000018be58 ((work_completion)(&rreq->work)){....}-{0:0}, at: process_one_work+0x1ec/0x6b0 kernel/workqueue.c:3205
2 locks held by kworker/u8:5/651:
#0: ffff888100078948 ((wq_completion)events_unbound){....}-{0:0}, at: process_one_work+0x442/0x6b0 kernel/workqueue.c:3204
#1: ffffc9000150fe58 ((work_completion)(&rreq->work)){....}-{0:0}, at: process_one_work+0x1ec/0x6b0 kernel/workqueue.c:3205
2 locks held by getty/843:
#0: ffff8881062a10a0 (&tty->ldisc_sem){....}-{0:0}, at: tty_ldisc_ref_wait+0x23/0x60 drivers/tty/tty_ldisc.c:243
#1: ffffc900001fb2f0 (&ldata->atomic_read_lock){....}-{3:3}, at: n_tty_read+0x521/0x670 drivers/tty/n_tty.c:2211
2 locks held by syz.3.17/2917:
#0: ffff888108ae03f8 (sb_writers#14){....}-{0:0}, at: do_pwritev+0x8d/0xc0 fs/read_write.c:1146
#1: ffff888113388148 (&sb->s_type->i_mutex_key#15){....}-{3:3}, at: netfs_start_io_direct+0x79/0xd0 fs/netfs/locking.c:188
2 locks held by syz.3.17/2918:
#0: ffff888108ae03f8 (sb_writers#14){....}-{0:0}, at: vfs_utimes+0x248/0x260 fs/utimes.c:36
#1: ffff888113388148 (&sb->s_type->i_mutex_key#15){....}-{3:3}, at: inode_lock include/linux/fs.h:831 [inline]
#1: ffff888113388148 (&sb->s_type->i_mutex_key#15){....}-{3:3}, at: vfs_utimes+0x123/0x260 fs/utimes.c:65
2 locks held by syz.4.18/3376:
#0: ffff88810f6903f8 (sb_writers#14){....}-{0:0}, at: do_pwritev+0x8d/0xc0 fs/read_write.c:1146
#1: ffff888113388720 (&sb->s_type->i_mutex_key#15){....}-{3:3}, at: netfs_start_io_direct+0x79/0xd0 fs/netfs/locking.c:188
2 locks held by syz.4.18/3378:
#0: ffff88810f6903f8 (sb_writers#14){....}-{0:0}, at: vfs_utimes+0x248/0x260 fs/utimes.c:36
#1: ffff888113388720 (&sb->s_type->i_mutex_key#15){....}-{3:3}, at: inode_lock include/linux/fs.h:831 [inline]
#1: ffff888113388720 (&sb->s_type->i_mutex_key#15){....}-{3:3}, at: vfs_utimes+0x123/0x260 fs/utimes.c:65
2 locks held by syz.5.19/3836:
#0: ffff88810d2d93f8 (sb_writers#14){....}-{0:0}, at: do_pwritev+0x8d/0xc0 fs/read_write.c:1146
#1: ffff888113320148 (&sb->s_type->i_mutex_key#15){....}-{3:3}, at: netfs_start_io_direct+0x79/0xd0 fs/netfs/locking.c:188
2 locks held by syz.5.19/3838:
#0: ffff88810d2d93f8 (sb_writers#14){....}-{0:0}, at: vfs_utimes+0x248/0x260 fs/utimes.c:36
#1: ffff888113320148 (&sb->s_type->i_mutex_key#15){....}-{3:3}, at: inode_lock include/linux/fs.h:831 [inline]
#1: ffff888113320148 (&sb->s_type->i_mutex_key#15){....}-{3:3}, at: vfs_utimes+0x123/0x260 fs/utimes.c:65
2 locks held by syz.6.20/4296:
#0: ffff88810839a3f8 (sb_writers#14){....}-{0:0}, at: do_pwritev+0x8d/0xc0 fs/read_write.c:1146
#1: ffff888113388cf8 (&sb->s_type->i_mutex_key#15){....}-{3:3}, at: netfs_start_io_direct+0x79/0xd0 fs/netfs/locking.c:188
2 locks held by syz.6.20/4298:
#0: ffff88810839a3f8 (sb_writers#14){....}-{0:0}, at: vfs_utimes+0x248/0x260 fs/utimes.c:36
#1: ffff888113388cf8 (&sb->s_type->i_mutex_key#15){....}-{3:3}, at: inode_lock include/linux/fs.h:831 [inline]
#1: ffff888113388cf8 (&sb->s_type->i_mutex_key#15){....}-{3:3}, at: vfs_utimes+0x123/0x260 fs/utimes.c:65
2 locks held by kworker/u8:6/4299:
#0: ffff888100078948 ((wq_completion)events_unbound){....}-{0:0}, at: process_one_work+0x442/0x6b0 kernel/workqueue.c:3204
#1: ffffc9000389fe58 ((work_completion)(&rreq->work)){....}-{0:0}, at: process_one_work+0x1ec/0x6b0 kernel/workqueue.c:3205
2 locks held by syz.7.21/4758:
#0: ffff8881063cb3f8 (sb_writers#14){....}-{0:0}, at: do_pwritev+0x8d/0xc0 fs/read_write.c:1146
#1: ffff8881133892d0 (&sb->s_type->i_mutex_key#15){....}-{3:3}, at: netfs_start_io_direct+0x79/0xd0 fs/netfs/locking.c:188
2 locks held by syz.7.21/4760:
#0: ffff8881063cb3f8 (sb_writers#14){....}-{0:0}, at: vfs_utimes+0x248/0x260 fs/utimes.c:36
#1: ffff8881133892d0 (&sb->s_type->i_mutex_key#15){....}-{3:3}, at: inode_lock include/linux/fs.h:831 [inline]
#1: ffff8881133892d0 (&sb->s_type->i_mutex_key#15){....}-{3:3}, at: vfs_utimes+0x123/0x260 fs/utimes.c:65
2 locks held by syz.8.22/5218:
#0: ffff8881063d73f8 (sb_writers#14){....}-{0:0}, at: do_pwritev+0x8d/0xc0 fs/read_write.c:1146
#1: ffff8881133898a8 (&sb->s_type->i_mutex_key#15){....}-{3:3}, at: netfs_start_io_direct+0x79/0xd0 fs/netfs/locking.c:188
2 locks held by syz.8.22/5220:
#0: ffff8881063d73f8 (sb_writers#14){....}-{0:0}, at: vfs_utimes+0x248/0x260 fs/utimes.c:36
#1: ffff8881133898a8 (&sb->s_type->i_mutex_key#15){....}-{3:3}, at: inode_lock include/linux/fs.h:831 [inline]
#1: ffff8881133898a8 (&sb->s_type->i_mutex_key#15){....}-{3:3}, at: vfs_utimes+0x123/0x260 fs/utimes.c:65
2 locks held by syz.9.23/5680:
#0: ffff88810cf553f8 (sb_writers#14){....}-{0:0}, at: do_pwritev+0x8d/0xc0 fs/read_write.c:1146
#1: ffff888113389e80 (&sb->s_type->i_mutex_key#15){....}-{3:3}, at: netfs_start_io_direct+0x79/0xd0 fs/netfs/locking.c:188
2 locks held by syz.9.23/5682:
#0: ffff88810cf553f8 (sb_writers#14){....}-{0:0}, at: vfs_utimes+0x248/0x260 fs/utimes.c:36
#1: ffff888113389e80 (&sb->s_type->i_mutex_key#15){....}-{3:3}, at: inode_lock include/linux/fs.h:831 [inline]
#1: ffff888113389e80 (&sb->s_type->i_mutex_key#15){....}-{3:3}, at: vfs_utimes+0x123/0x260 fs/utimes.c:65
2 locks held by kworker/u8:10/5683:
#0: ffff888100078948 ((wq_completion)events_unbound){....}-{0:0}, at: process_one_work+0x442/0x6b0 kernel/workqueue.c:3204
#1: ffffc90005177e58 ((work_completion)(&rreq->work)){....}-{0:0}, at: process_one_work+0x1ec/0x6b0 kernel/workqueue.c:3205
2 locks held by syz.0.24/6141:
#0: ffff8881062ba3f8 (sb_writers#14){....}-{0:0}, at: do_pwritev+0x8d/0xc0 fs/read_write.c:1146
#1: ffff888113320720 (&sb->s_type->i_mutex_key#15){....}-{3:3}, at: netfs_start_io_direct+0x79/0xd0 fs/netfs/locking.c:188
2 locks held by syz.0.24/6143:
#0: ffff8881062ba3f8 (sb_writers#14){....}-{0:0}, at: vfs_utimes+0x248/0x260 fs/utimes.c:36
#1: ffff888113320720 (&sb->s_type->i_mutex_key#15){....}-{3:3}, at: inode_lock include/linux/fs.h:831 [inline]
#1: ffff888113320720 (&sb->s_type->i_mutex_key#15){....}-{3:3}, at: vfs_utimes+0x123/0x260 fs/utimes.c:65
2 locks held by kworker/u8:11/6144:
#0: ffff888100078948 ((wq_completion)events_unbound){....}-{0:0}, at: process_one_work+0x442/0x6b0 kernel/workqueue.c:3204
#1: ffffc900059cfe58 ((work_completion)(&rreq->work)){....}-{0:0}, at: process_one_work+0x1ec/0x6b0 kernel/workqueue.c:3205
2 locks held by syz.1.25/6602:
#0: ffff88810c7c73f8 (sb_writers#14){....}-{0:0}, at: do_pwritev+0x8d/0xc0 fs/read_write.c:1146
#1: ffff888113320cf8 (&sb->s_type->i_mutex_key#15){....}-{3:3}, at: netfs_start_io_direct+0x79/0xd0 fs/netfs/locking.c:188
2 locks held by syz.1.25/6603:
#0: ffff88810c7c73f8 (sb_writers#14){....}-{0:0}, at: vfs_utimes+0x248/0x260 fs/utimes.c:36
#1: ffff888113320cf8 (&sb->s_type->i_mutex_key#15){....}-{3:3}, at: inode_lock include/linux/fs.h:831 [inline]
#1: ffff888113320cf8 (&sb->s_type->i_mutex_key#15){....}-{3:3}, at: vfs_utimes+0x123/0x260 fs/utimes.c:65
2 locks held by kworker/u8:12/6604:
#0: ffff888100078948 ((wq_completion)events_unbound){....}-{0:0}, at: process_one_work+0x442/0x6b0 kernel/workqueue.c:3204
#1: ffffc90006107e58 ((work_completion)(&rreq->work)){....}-{0:0}, at: process_one_work+0x1ec/0x6b0 kernel/workqueue.c:3205
2 locks held by syz.2.26/7062:
#0: ffff88810bb393f8 (sb_writers#14){....}-{0:0}, at: do_pwritev+0x8d/0xc0 fs/read_write.c:1146
#1: ffff8881133212d0 (&sb->s_type->i_mutex_key#15){....}-{3:3}, at: netfs_start_io_direct+0x79/0xd0 fs/netfs/locking.c:188
2 locks held by syz.2.26/7064:
#0: ffff88810bb393f8 (sb_writers#14){....}-{0:0}, at: vfs_utimes+0x248/0x260 fs/utimes.c:36
#1: ffff8881133212d0 (&sb->s_type->i_mutex_key#15){....}-{3:3}, at: inode_lock include/linux/fs.h:831 [inline]
#1: ffff8881133212d0 (&sb->s_type->i_mutex_key#15){....}-{3:3}, at: vfs_utimes+0x123/0x260 fs/utimes.c:65
=============================================
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 30 Comm: khungtaskd Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/18/2025
Call Trace:
__dump_stack lib/dump_stack.c:94 [inline]
dump_stack_lvl+0x5a/0x90 lib/dump_stack.c:120
nmi_cpu_backtrace+0xd4/0x110 lib/nmi_backtrace.c:113
nmi_trigger_cpumask_backtrace+0xd5/0x140 lib/nmi_backtrace.c:62
trigger_all_cpu_backtrace include/linux/nmi.h:162 [inline]
check_hung_uninterruptible_tasks kernel/hung_task.c:234 [inline]
watchdog+0x648/0x680 kernel/hung_task.c:397
kthread+0xd6/0x100 kernel/kthread.c:389
ret_from_fork+0x2c/0x50 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1 skipped: idling at native_safe_halt arch/x86/include/asm/irqflags.h:48 [inline]
NMI backtrace for cpu 1 skipped: idling at arch_safe_halt arch/x86/include/asm/irqflags.h:106 [inline]
NMI backtrace for cpu 1 skipped: idling at acpi_safe_halt+0x1a/0x20 drivers/acpi/processor_idle.c:111