INFO: task syz-executor:4167 blocked for more than 143 seconds.
      Not tainted 5.15.178-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor    state:D stack:19448 pid: 4167 ppid:     1 flags:0x00004004
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5027 [inline]
 __schedule+0x12c4/0x45b0 kernel/sched/core.c:6373
 schedule+0x11b/0x1f0 kernel/sched/core.c:6456
 io_schedule+0x88/0x100 kernel/sched/core.c:8481
 wait_on_page_bit_common+0xa13/0x1180 mm/filemap.c:1356
 lock_page include/linux/pagemap.h:625 [inline]
 truncate_inode_pages_range+0xc17/0x1290 mm/truncate.c:394
 evict+0x53c/0x930 fs/inode.c:624
 dispose_list fs/inode.c:655 [inline]
 evict_inodes+0x668/0x700 fs/inode.c:709
 generic_shutdown_super+0x94/0x310 fs/super.c:454
 kill_block_super+0x7a/0xe0 fs/super.c:1427
 deactivate_locked_super+0xa0/0x110 fs/super.c:335
 cleanup_mnt+0x44e/0x500 fs/namespace.c:1143
 task_work_run+0x129/0x1a0 kernel/task_work.c:188
 tracehook_notify_resume include/linux/tracehook.h:189 [inline]
 exit_to_user_mode_loop+0x106/0x130 kernel/entry/common.c:181
 exit_to_user_mode_prepare+0xb1/0x140 kernel/entry/common.c:214
 __syscall_exit_to_user_mode_work kernel/entry/common.c:296 [inline]
 syscall_exit_to_user_mode+0x5d/0x240 kernel/entry/common.c:307
 do_syscall_64+0x47/0xb0 arch/x86/entry/common.c:86
 entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7f6099c56117
RSP: 002b:00007ffd3054e9e8 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6
RAX: 0000000000000000 RBX: 00007f6099cd608c RCX: 00007f6099c56117
RDX: 0000000000000000 RSI: 0000000000000009 RDI: 00007ffd3054eaa0
RBP: 00007ffd3054eaa0 R08: 0000000000000000 R09: 0000000000000000
R10: 00000000ffffffff R11: 0000000000000246 R12: 00007ffd3054fb30
R13: 00007f6099cd608c R14: 000000000003baea R15: 00007ffd3054fb70
 </TASK>

Showing all locks held in the system:
1 lock held by khungtaskd/27:
 #0: ffffffff8cb1fce0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire+0x0/0x30
2 locks held by getty/3926:
 #0: ffff88802c4dc098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x21/0x70 drivers/tty/tty_ldisc.c:252
 #1: ffffc900025c62e8 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x6af/0x1db0 drivers/tty/n_tty.c:2158
1 lock held by syz-executor/4167:
 #0: ffff88805e35e0e0 (&type->s_umount_key#68){+.+.}-{3:3}, at: deactivate_super+0xa9/0xe0 fs/super.c:365
3 locks held by kworker/1:13/5064:
 #0: ffff8881423a1538 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_one_work+0x78a/0x10c0 kernel/workqueue.c:2283
 #1: ffffc900038ffd20 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_one_work+0x7d0/0x10c0 kernel/workqueue.c:2285
 #2: ffff888147fea220 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:760 [inline]
 #2: ffff888147fea220 (&dev->mutex){....}-{3:3}, at: hub_event+0x208/0x54c0 drivers/usb/core/hub.c:5771
1 lock held by udevd/12625:
 #0: ffff888020eff118 (&disk->open_mutex){+.+.}-{3:3}, at: blkdev_get_by_dev+0x14d/0xa50 block/bdev.c:817
2 locks held by syz.3.6622/18940:
 #0: ffff888020eff118 (&disk->open_mutex){+.+.}-{3:3}, at: blkdev_put+0xfb/0x790 block/bdev.c:912
 #1: ffff88802104d468 (&lo->lo_mutex){+.+.}-{3:3}, at: lo_release+0x4d/0x1f0 drivers/block/loop.c:2070

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

NMI backtrace for cpu 0
CPU: 0 PID: 27 Comm: khungtaskd Not tainted 5.15.178-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 12/27/2024
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0x1e3/0x2d0 lib/dump_stack.c:106
 nmi_cpu_backtrace+0x46a/0x4a0 lib/nmi_backtrace.c:111
 nmi_trigger_cpumask_backtrace+0x181/0x2a0 lib/nmi_backtrace.c:62
 trigger_all_cpu_backtrace include/linux/nmi.h:148 [inline]
 check_hung_uninterruptible_tasks kernel/hung_task.c:210 [inline]
 watchdog+0xe72/0xeb0 kernel/hung_task.c:295
 kthread+0x3f6/0x4f0 kernel/kthread.c:334
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287
 </TASK>
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 PID: 5064 Comm: kworker/1:13 Not tainted 5.15.178-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 12/27/2024
Workqueue: usb_hub_wq hub_event
RIP: 0010:io_serial_out+0x7a/0xb0 drivers/tty/serial/8250/8250_port.c:468
Code: fc 89 e9 41 d3 e7 48 83 c3 40 48 89 d8 48 c1 e8 03 42 80 3c 20 00 74 08 48 89 df e8 a0 3c 44 fd 44 03 3b 44 89 f0 44 89 fa ee <5b> 41 5c 41 5e 41 5f 5d c3 89 e9 80 e1 07 38 c1 7c ab 48 89 ef e8
RSP: 0018:ffffc900038fe850 EFLAGS: 00000006
RAX: 0000000000000000 RBX: ffffffff96db9a00 RCX: 0000000000000000
RDX: 00000000000003f9 RSI: 00000000000849e4 RDI: 00000000000849e5
RBP: 0000000000000000 R08: ffffffff84863127 R09: 0000000000000003
R10: ffffffffffffffff R11: dffffc0000000001 R12: dffffc0000000000
R13: 1ffffffff2db7342 R14: 0000000000000000 R15: 00000000000003f9
FS:  0000000000000000(0000) GS:ffff8880b8f00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000555566c365c8 CR3: 0000000023ee9000 CR4: 00000000003506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <NMI>
 </NMI>
 <TASK>
 serial8250_console_write+0x319/0x1180
 console_unlock+0xced/0x12b0 kernel/printk/printk.c:2744
 vprintk_emit+0xbf/0x150 kernel/printk/printk.c:2274
 _printk+0xd1/0x120 kernel/printk/printk.c:2299
 gspca_dev_probe2+0xbe/0x1350 drivers/media/usb/gspca/gspca.c:1453
 usb_probe_interface+0x5c0/0xaf0 drivers/usb/core/driver.c:396
 really_probe+0x24e/0xb60 drivers/base/dd.c:595
 __driver_probe_device+0x1a2/0x3d0 drivers/base/dd.c:755
 driver_probe_device+0x50/0x420 drivers/base/dd.c:785
 __device_attach_driver+0x2b9/0x500 drivers/base/dd.c:907
 bus_for_each_drv+0x183/0x200 drivers/base/bus.c:429
 __device_attach+0x359/0x570 drivers/base/dd.c:979
 bus_probe_device+0xba/0x1e0 drivers/base/bus.c:489
 device_add+0xb48/0xfd0 drivers/base/core.c:3412
 usb_set_configuration+0x19dd/0x2020 drivers/usb/core/message.c:2165
 usb_generic_driver_probe+0x84/0x140 drivers/usb/core/generic.c:238
 usb_probe_device+0x130/0x260 drivers/usb/core/driver.c:293
 really_probe+0x24e/0xb60 drivers/base/dd.c:595
 __driver_probe_device+0x1a2/0x3d0 drivers/base/dd.c:755
 driver_probe_device+0x50/0x420 drivers/base/dd.c:785
 __device_attach_driver+0x2b9/0x500 drivers/base/dd.c:907
 bus_for_each_drv+0x183/0x200 drivers/base/bus.c:429
 __device_attach+0x359/0x570 drivers/base/dd.c:979
 bus_probe_device+0xba/0x1e0 drivers/base/bus.c:489
 device_add+0xb48/0xfd0 drivers/base/core.c:3412
 usb_new_device+0xc21/0x18f0 drivers/usb/core/hub.c:2593
 hub_port_connect drivers/usb/core/hub.c:5457 [inline]
 hub_port_connect_change drivers/usb/core/hub.c:5597 [inline]
 port_event drivers/usb/core/hub.c:5743 [inline]
 hub_event+0x2cdf/0x54c0 drivers/usb/core/hub.c:5825
 process_one_work+0x8a1/0x10c0 kernel/workqueue.c:2310
 worker_thread+0xaca/0x1280 kernel/workqueue.c:2457
 kthread+0x3f6/0x4f0 kernel/kthread.c:334
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287
 </TASK>