INFO: task syz.0.2086:14345 blocked for more than 144 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.0.2086      state:D stack:28296 pid:14345 tgid:14343 ppid:5810   task_flags:0x400140 flags:0x00080002
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5325 [inline]
 __schedule+0x1190/0x5de0 kernel/sched/core.c:6929
 __schedule_loop kernel/sched/core.c:7011 [inline]
 schedule+0xe7/0x3a0 kernel/sched/core.c:7026
 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7083
 __mutex_lock_common kernel/locking/mutex.c:676 [inline]
 __mutex_lock+0x818/0x1060 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
 setup_bdev_super+0x39b/0x730 fs/super.c:1609
 get_tree_bdev_flags+0x363/0x620 fs/super.c:1689
 vfs_get_tree+0x8e/0x340 fs/super.c:1751
 fc_mount fs/namespace.c:1208 [inline]
 do_new_mount_fc fs/namespace.c:3651 [inline]
 do_new_mount fs/namespace.c:3727 [inline]
 path_mount+0x7b9/0x23a0 fs/namespace.c:4037
 do_mount fs/namespace.c:4050 [inline]
 __do_sys_mount fs/namespace.c:4238 [inline]
 __se_sys_mount fs/namespace.c:4215 [inline]
 __x64_sys_mount+0x293/0x310 fs/namespace.c:4215
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xcd/0xfa0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7efcd678eec9
RSP: 002b:00007efcd767f038 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5
RAX: ffffffffffffffda RBX: 00007efcd69e5fa0 RCX: 00007efcd678eec9
RDX: 0000200000000080 RSI: 0000200000000000 RDI: 00002000000000c0
RBP: 00007efcd6811f91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000008000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007efcd69e6038 R14: 00007efcd69e5fa0 R15: 00007ffc61666228
 </TASK>

Showing all locks held in the system:
1 lock held by khungtaskd/31:
 #0: ffffffff8e3c44a0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
 #0: ffffffff8e3c44a0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:867 [inline]
 #0: ffffffff8e3c44a0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x36/0x1c0 kernel/locking/lockdep.c:6775
2 locks held by getty/5576:
 #0: ffff88814d3270a0 (&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/5811:
 #0: ffff888026509358 (&disk->open_mutex){+.+.}-{4:4}, at: bdev_open+0x41a/0xe40 block/bdev.c:945
1 lock held by udevd/5822:
 #0: ffff8880262c7358 (&disk->open_mutex){+.+.}-{4:4}, at: bdev_open+0x41a/0xe40 block/bdev.c:945
1 lock held by udevd/6391:
 #0: ffff888141b19358 (&disk->open_mutex){+.+.}-{4:4}, at: bdev_open+0x41a/0xe40 block/bdev.c:945
1 lock held by udevd/6767:
 #0: ffff8880263e1358 (&disk->open_mutex){+.+.}-{4:4}, at: bdev_open+0x41a/0xe40 block/bdev.c:945
1 lock held by udevd/8051:
 #0: ffff88802650b358 (&disk->open_mutex){+.+.}-{4:4}, at: bdev_open+0x41a/0xe40 block/bdev.c:945
2 locks held by syz.0.2086/14345:
 #0: ffff8880252640e0 (&type->s_umount_key#90/1){+.+.}-{4:4}, at: alloc_super+0x1e3/0xb60 fs/super.c:344
 #1: ffff8880262c7358 (&disk->open_mutex){+.+.}-{4:4}, at: bdev_open+0xa2/0xe40 block/bdev.c:945

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

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 10/02/2025
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:160 [inline]
 check_hung_uninterruptible_tasks kernel/hung_task.c:332 [inline]
 watchdog+0xf3f/0x1170 kernel/hung_task.c:495
 kthread+0x3c2/0x780 kernel/kthread.c:463
 ret_from_fork+0x672/0x7d0 arch/x86/kernel/process.c:158
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
 </TASK>
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 16269 Comm: syz.6.2601 Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/02/2025
RIP: 0033:0x7fd01d8681d7
Code: 00 00 00 48 8b 70 f8 48 83 e8 08 48 39 f2 72 f3 48 39 c3 73 3e 48 89 33 48 83 c3 08 48 8b 70 f8 48 89 08 48 8b 0b 49 8b 14 24 <eb> bf 48 39 f2 72 97 48 39 f0 73 46 49 89 34 24 48 89 ce 48 89 4f
RSP: 002b:00007ffe0e317460 EFLAGS: 00000216
RAX: 00007fd01c6876c0 RBX: 00007fd01c687460 RCX: ffffffff819b590f
RDX: ffffffff819b590f RSI: ffffffff819b590f RDI: 00007fd01c687750
RBP: 00007fd01c6873d0 R08: 00007fd01c687588 R09: 00007fd01dbd2000
R10: 00007fd01c3f9008 R11: 00000000000000ff R12: 00007fd01c6873c8
R13: 0000000000000015 R14: 00007ffe0e3176e8 R15: 00007fd01c3f9008
FS:  000055555c175500 GS:  0000000000000000