INFO: task syz.2.478:7433 blocked for more than 144 seconds.
      Not tainted 6.13.0-syzkaller-08265-g9c5968db9e62 #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.2.478       state:D stack:28192 pid:7433  tgid:7429  ppid:5814   task_flags:0x400140 flags:0x00004004
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5377 [inline]
 __schedule+0xf43/0x5890 kernel/sched/core.c:6764
 __schedule_loop kernel/sched/core.c:6841 [inline]
 schedule+0xe7/0x350 kernel/sched/core.c:6856
 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6913
 __mutex_lock_common kernel/locking/mutex.c:662 [inline]
 __mutex_lock+0x6bd/0xb10 kernel/locking/mutex.c:730
 sync_bdevs+0xfd/0x360 block/bdev.c:1246
 ksys_sync+0xb3/0x150 fs/sync.c:105
 __do_sys_sync+0xe/0x20 fs/sync.c:113
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xcd/0x250 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f00d898cda9
RSP: 002b:00007f00d97d8038 EFLAGS: 00000246 ORIG_RAX: 00000000000000a2
RAX: ffffffffffffffda RBX: 00007f00d8ba6160 RCX: 00007f00d898cda9
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 00007f00d8ba6160 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007f00d8ba6160 R15: 00007ffc70c5e718
 </TASK>

Showing all locks held in the system:
1 lock held by khungtaskd/30:
 #0: ffffffff8e1be000 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:337 [inline]
 #0: ffffffff8e1be000 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline]
 #0: ffffffff8e1be000 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x7f/0x390 kernel/locking/lockdep.c:6746
2 locks held by getty/5579:
 #0: ffff88803736a0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x24/0x80 drivers/tty/tty_ldisc.c:243
 #1: ffffc90002fde2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0xfba/0x1480 drivers/tty/n_tty.c:2211
1 lock held by syz-executor/5803:
 #0: ffff8880b862c698 (hrtimer_bases.lock){-.-.}-{2:2}, at: lock_hrtimer_base kernel/time/hrtimer.c:175 [inline]
 #0: ffff8880b862c698 (hrtimer_bases.lock){-.-.}-{2:2}, at: hrtimer_start_range_ns+0x118/0xc70 kernel/time/hrtimer.c:1290
1 lock held by udevd/5807:
 #0: ffff88805037a4c8 (&disk->open_mutex){+.+.}-{4:4}, at: bdev_open+0x41a/0xe20 block/bdev.c:903
3 locks held by kworker/u8:9/6143:
1 lock held by syz.2.478/7433:
 #0: ffff88805037a4c8 (&disk->open_mutex){+.+.}-{4:4}, at: sync_bdevs+0xfd/0x360 block/bdev.c:1246
1 lock held by syz.0.1054/9373:

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

NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 30 Comm: khungtaskd Not tainted 6.13.0-syzkaller-08265-g9c5968db9e62 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 12/27/2024
Call Trace:
 <TASK>
 __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:162 [inline]
 check_hung_uninterruptible_tasks kernel/hung_task.c:236 [inline]
 watchdog+0xf62/0x12b0 kernel/hung_task.c:399
 kthread+0x3af/0x750 kernel/kthread.c:464
 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:148
 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: 5803 Comm: syz-executor Not tainted 6.13.0-syzkaller-08265-g9c5968db9e62 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 12/27/2024
RIP: 0010:ktime_get+0x1d/0x310 kernel/time/timekeeping.c:747
Code: 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 41 57 41 56 41 55 41 54 55 53 48 83 ec 08 e8 59 2e 12 00 8b 1d 2f ca ba 0e <31> ff 89 de e8 4a 29 12 00 85 db 0f 85 6d 02 00 00 49 bd 00 00 00
RSP: 0018:ffffc9000450fba0 EFLAGS: 00000093
RAX: 0000000000000000 RBX: 0000000000000000 RCX: ffffffff81a6f950
RDX: ffff88802a9cc880 RSI: ffffffff81a78057 RDI: ffff8880b862c760
RBP: 00000000000f4240 R08: 0000000000000005 R09: 0000000000000000
R10: 0000000000000001 R11: 0000000000000000 R12: 00000000b862c600
R13: ffffc9000450fd78 R14: 0000000000000001 R15: ffff8880b862c700
FS:  000055558fb2f500(0000) GS:ffff8880b8600000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fda96d79178 CR3: 000000002dd04000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <NMI>
 </NMI>
 <TASK>
 __hrtimer_start_range_ns kernel/time/hrtimer.c:1236 [inline]
 hrtimer_start_range_ns+0x273/0xc70 kernel/time/hrtimer.c:1292
 hrtimer_start_expires include/linux/hrtimer.h:274 [inline]
 hrtimer_sleeper_start_expires kernel/time/hrtimer.c:2000 [inline]
 do_nanosleep+0x1f3/0x510 kernel/time/hrtimer.c:2075
 hrtimer_nanosleep+0x158/0x380 kernel/time/hrtimer.c:2125
 common_nsleep+0xa1/0xd0 kernel/time/posix-timers.c:1356
 __do_sys_clock_nanosleep kernel/time/posix-timers.c:1402 [inline]
 __se_sys_clock_nanosleep kernel/time/posix-timers.c:1379 [inline]
 __x64_sys_clock_nanosleep+0x344/0x4a0 kernel/time/posix-timers.c:1379
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xcd/0x250 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f610a5bf623
Code: 1f 84 00 00 00 00 00 83 ff 03 74 7b 83 ff 02 b8 fa ff ff ff 49 89 ca 0f 44 f8 80 3d 1e df 1b 00 00 74 14 b8 e6 00 00 00 0f 05 <f7> d8 c3 66 2e 0f 1f 84 00 00 00 00 00 48 83 ec 28 48 89 54 24 10
RSP: 002b:00007fff2febc4a8 EFLAGS: 00000202 ORIG_RAX: 00000000000000e6
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f610a5bf623
RDX: 00007fff2febc4c0 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 0000000000000000 R08: 000000000000ff3e R09: 00007f610b32c000
R10: 0000000000000000 R11: 0000000000000202 R12: 00007fff2febc910
R13: 0000000000000004 R14: 00007fff2febc4fc R15: 00007fff2febc590
 </TASK>
vkms_vblank_simulate: vblank timer overrun