INFO: task syz.2.251:6994 blocked for more than 143 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.2.251 state:D stack:27096 pid:6994 tgid:6984 ppid:5842 task_flags:0x400140 flags:0x00004004
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
bdev_open+0xa2/0xe40 block/bdev.c:945
bdev_file_open_by_dev block/bdev.c:1059 [inline]
bdev_file_open_by_dev+0x182/0x210 block/bdev.c:1034
swsusp_check+0x72/0x440 kernel/power/swap.c:1577
software_resume+0x6f/0x4e0 kernel/power/hibernate.c:1039
resume_store+0x247/0x460 kernel/power/hibernate.c:1324
kobj_attr_store+0x55/0x80 lib/kobject.c:840
sysfs_kf_write+0xef/0x150 fs/sysfs/file.c:145
kernfs_fop_write_iter+0x351/0x510 fs/kernfs/file.c:334
new_sync_write fs/read_write.c:593 [inline]
vfs_write+0x7d3/0x11d0 fs/read_write.c:686
ksys_write+0x12a/0x250 fs/read_write.c:738
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xcd/0x4c0 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f40b5f8ebe9
RSP: 002b:00007f40b41f6038 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 00007f40b61c6180 RCX: 00007f40b5f8ebe9
RDX: 0000000000000012 RSI: 0000200000000000 RDI: 0000000000000009
RBP: 00007f40b6011e19 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f40b61c6218 R14: 00007f40b61c6180 R15: 00007ffe218cc288
Showing all locks held in the system:
1 lock held by khungtaskd/31:
#0: ffffffff8e5c1260 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
#0: ffffffff8e5c1260 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline]
#0: ffffffff8e5c1260 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x36/0x1c0 kernel/locking/lockdep.c:6775
2 locks held by getty/5604:
#0: ffff88814da950a0 (&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
1 lock held by udevd/5848:
#0: ffff888143302358 (&disk->open_mutex){+.+.}-{4:4}, at: bdev_open+0x41a/0xe40 block/bdev.c:945
6 locks held by syz.2.251/6994:
#0: ffff8880755100f8 (&f->f_pos_lock){+.+.}-{4:4}, at: fdget_pos+0x2a2/0x370 fs/file.c:1232
#1: ffff88807dc02428 (sb_writers#8){.+.+}-{0:0}, at: ksys_write+0x12a/0x250 fs/read_write.c:738
#2: ffff888079084088 (&of->mutex){+.+.}-{4:4}, at: kernfs_fop_write_iter+0x28f/0x510 fs/kernfs/file.c:325
#3: ffff88801f2dd878 (kn->active#65){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x2b2/0x510 fs/kernfs/file.c:326
#4: ffffffff8e4849c8 (system_transition_mutex){+.+.}-{4:4}, at: software_resume+0x65/0x4e0 kernel/power/hibernate.c:1038
#5: ffff888143302358 (&disk->open_mutex){+.+.}-{4:4}, at: bdev_open+0xa2/0xe40 block/bdev.c:945
2 locks held by syz.5.539/8395:
#0: ffffffff8f3041e8 (misc_mtx){+.+.}-{4:4}, at: misc_open+0x63/0x420 drivers/char/misc.c:125
#1: ffffffff8e4849c8 (system_transition_mutex){+.+.}-{4:4}, at: lock_system_sleep+0x87/0xa0 kernel/power/main.c:57
1 lock held by syz.3.546/8421:
#0: ffffffff8f3041e8 (misc_mtx){+.+.}-{4:4}, at: misc_open+0x63/0x420 drivers/char/misc.c:125
1 lock held by syz.4.557/8462:
#0: ffffffff8f3041e8 (misc_mtx){+.+.}-{4:4}, at: misc_open+0x63/0x420 drivers/char/misc.c:125
1 lock held by syz.4.557/8467:
#0: ffffffff8f3041e8 (misc_mtx){+.+.}-{4:4}, at: misc_open+0x63/0x420 drivers/char/misc.c:125
1 lock held by syz-executor/8574:
#0: ffffffff8f3041e8 (misc_mtx){+.+.}-{4:4}, at: misc_open+0x63/0x420 drivers/char/misc.c:125
1 lock held by syz-executor/8597:
#0: ffffffff8f3041e8 (misc_mtx){+.+.}-{4:4}, at: misc_open+0x63/0x420 drivers/char/misc.c:125
1 lock held by syz-executor/8648:
#0: ffffffff8f3041e8 (misc_mtx){+.+.}-{4:4}, at: misc_open+0x63/0x420 drivers/char/misc.c:125
1 lock held by syz.0.633/8687:
#0: ffff888143302358 (&disk->open_mutex){+.+.}-{4:4}, at: sync_bdevs+0xfd/0x360 block/bdev.c:1288
1 lock held by syz-executor/8858:
#0: ffffffff8f3041e8 (misc_mtx){+.+.}-{4:4}, at: misc_open+0x63/0x420 drivers/char/misc.c:125
1 lock held by syz-executor/9064:
#0: ffffffff8f3041e8 (misc_mtx){+.+.}-{4:4}, at: misc_open+0x63/0x420 drivers/char/misc.c:125
=============================================
NMI backtrace for cpu 1
CPU: 1 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+0x3c2/0x780 kernel/kthread.c:463
ret_from_fork+0x5d4/0x6f0 arch/x86/kernel/process.c:148
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 11 Comm: kworker/0:0H Not tainted syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025
Workqueue: kblockd blk_mq_timeout_work
RIP: 0010:format_decode+0x30a/0xd40 lib/vsprintf.c:2691
Code: c2 40 84 d6 0f 85 e4 08 00 00 4c 89 f9 41 c7 46 04 ff ff ff ff 48 ba 00 00 00 00 00 fc ff df 48 c1 e9 03 0f b6 14 11 4c 89 f9 <83> e1 07 38 ca 7f 08 84 d2 0f 85 c4 08 00 00 44 0f b6 7b 01 bf 09
RSP: 0018:ffffc90000106de8 EFLAGS: 00000a06
RAX: 0000000000000000 RBX: ffffffff8badfd00 RCX: ffffffff8badfd01
RDX: 0000000000000005 RSI: 0000000000000001 RDI: ffffc90000106f0c
RBP: ffffc90000106e88 R08: 0000000000000001 R09: 0000000000000010
R10: 0000000000000043 R11: 000000000000e228 R12: 0000000000000043
R13: ffffffff8badfd01 R14: ffffc90000106f08 R15: ffffffff8badfd01
FS: 0000000000000000(0000) GS:ffff8881246b5000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055556d5345c8 CR3: 000000007c6ce000 CR4: 00000000003526f0
Call Trace:
vsnprintf+0x156/0x1160 lib/vsprintf.c:2869
snprintf+0xc7/0x100 lib/vsprintf.c:3020
print_caller kernel/printk/printk.c:1390 [inline]
info_print_prefix+0x134/0x350 kernel/printk/printk.c:1409
record_print_text+0x140/0x400 kernel/printk/printk.c:1456
printk_get_next_message+0x2d1/0x6d0 kernel/printk/printk.c:3024
console_emit_next_record kernel/printk/printk.c:3092 [inline]
console_flush_all+0x6ea/0xc60 kernel/printk/printk.c:3226
__console_flush_and_unlock kernel/printk/printk.c:3285 [inline]
console_unlock+0xd8/0x210 kernel/printk/printk.c:3325
vprintk_emit+0x418/0x6d0 kernel/printk/printk.c:2450
dev_vprintk_emit drivers/base/core.c:4914 [inline]
dev_printk_emit+0xfa/0x140 drivers/base/core.c:4925
__dev_printk+0xf5/0x270 drivers/base/core.c:4937
_dev_info+0xe4/0x120 drivers/base/core.c:4983
nbd_xmit_timeout+0x58b/0xdb0 drivers/block/nbd.c:520
blk_mq_rq_timed_out block/blk-mq.c:1635 [inline]
blk_mq_handle_expired+0x210/0x2c0 block/blk-mq.c:1703
bt_iter+0x288/0x320 block/blk-mq-tag.c:292
__sbitmap_for_each_set include/linux/sbitmap.h:269 [inline]
sbitmap_for_each_set include/linux/sbitmap.h:290 [inline]
bt_for_each block/blk-mq-tag.c:324 [inline]
blk_mq_queue_tag_busy_iter+0xc16/0x1970 block/blk-mq-tag.c:533
blk_mq_timeout_work+0x511/0x6d0 block/blk-mq.c:1745
process_one_work+0x9cc/0x1b70 kernel/workqueue.c:3236
process_scheduled_works kernel/workqueue.c:3319 [inline]
worker_thread+0x6c8/0xf10 kernel/workqueue.c:3400
kthread+0x3c2/0x780 kernel/kthread.c:463
ret_from_fork+0x5d4/0x6f0 arch/x86/kernel/process.c:148
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245