syzbot

INFO: task syz-executor.0:9042 blocked for more than 430 seconds.
      Not tainted 5.16.0-rc1-syzkaller-00313-ga90af8f15bdc #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor.0  state:D stack:    0 pid: 9042 ppid:  2197 flags:0x00000009
Call trace:
 __switch_to+0x274/0x3b4 arch/arm64/kernel/process.c:526
 context_switch kernel/sched/core.c:4972 [inline]
 __schedule+0x818/0x1be0 kernel/sched/core.c:6253
 schedule+0xb8/0x224 kernel/sched/core.c:6326
 blk_mq_freeze_queue_wait+0xf4/0x130 block/blk-mq.c:178
 blk_freeze_queue block/blk-mq.c:205 [inline]
 blk_mq_freeze_queue+0x20/0x30 block/blk-mq.c:214
 nbd_add_socket+0x134/0x690 drivers/block/nbd.c:1109
 __nbd_ioctl drivers/block/nbd.c:1454 [inline]
 nbd_ioctl+0x42c/0x8f0 drivers/block/nbd.c:1511
 blkdev_ioctl+0x238/0x950 block/ioctl.c:609
 vfs_ioctl fs/ioctl.c:51 [inline]
 __do_sys_ioctl fs/ioctl.c:874 [inline]
 __se_sys_ioctl fs/ioctl.c:860 [inline]
 __arm64_sys_ioctl+0x120/0x18c fs/ioctl.c:860
 __invoke_syscall arch/arm64/kernel/syscall.c:38 [inline]
 invoke_syscall+0x6c/0x260 arch/arm64/kernel/syscall.c:52
 el0_svc_common.constprop.0+0xc4/0x254 arch/arm64/kernel/syscall.c:142
 do_el0_svc+0xa0/0xcc arch/arm64/kernel/syscall.c:181
 el0_svc+0x64/0x290 arch/arm64/kernel/entry-common.c:603
 el0t_64_sync_handler+0x1a4/0x1b0 arch/arm64/kernel/entry-common.c:621
 el0t_64_sync+0x1a0/0x1a4 arch/arm64/kernel/entry.S:572
INFO: task syz-executor.0:9046 blocked for more than 430 seconds.
      Not tainted 5.16.0-rc1-syzkaller-00313-ga90af8f15bdc #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor.0  state:D stack:    0 pid: 9046 ppid:  2197 flags:0x00000001
Call trace:
 __switch_to+0x274/0x3b4 arch/arm64/kernel/process.c:526
 context_switch kernel/sched/core.c:4972 [inline]
 __schedule+0x818/0x1be0 kernel/sched/core.c:6253
 schedule+0xb8/0x224 kernel/sched/core.c:6326
 schedule_preempt_disabled+0x18/0x30 kernel/sched/core.c:6385
 __mutex_lock_common kernel/locking/mutex.c:680 [inline]
 __mutex_lock+0x3c0/0x7ec kernel/locking/mutex.c:740
 mutex_lock_nested+0x78/0x100 kernel/locking/mutex.c:792
 nbd_ioctl+0x108/0x8f0 drivers/block/nbd.c:1504
 blkdev_ioctl+0x238/0x950 block/ioctl.c:609
 vfs_ioctl fs/ioctl.c:51 [inline]
 __do_sys_ioctl fs/ioctl.c:874 [inline]
 __se_sys_ioctl fs/ioctl.c:860 [inline]
 __arm64_sys_ioctl+0x120/0x18c fs/ioctl.c:860
 __invoke_syscall arch/arm64/kernel/syscall.c:38 [inline]
 invoke_syscall+0x6c/0x260 arch/arm64/kernel/syscall.c:52
 el0_svc_common.constprop.0+0xc4/0x254 arch/arm64/kernel/syscall.c:142
 do_el0_svc+0xa0/0xcc arch/arm64/kernel/syscall.c:181
 el0_svc+0x64/0x290 arch/arm64/kernel/entry-common.c:603
 el0t_64_sync_handler+0x1a4/0x1b0 arch/arm64/kernel/entry-common.c:621
 el0t_64_sync+0x1a0/0x1a4 arch/arm64/kernel/entry.S:572

Showing all locks held in the system:
1 lock held by khungtaskd/27:
 #0: ffff800015e18f20 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x74/0x25c kernel/locking/lockdep.c:6460
1 lock held by klogd/1985:
1 lock held by dhcpcd/2029:
2 locks held by getty/2146:
 #0: ffff00000a266098 (&tty->ldisc_sem){++++}-{0:0}, at: ldsem_down_read+0x3c/0x50 drivers/tty/tty_ldsem.c:340
 #1: ffff80001886b2e8 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x810/0xbe0 drivers/tty/n_tty.c:2113
4 locks held by kworker/0:1/5013:
1 lock held by syz-executor.0/9042:
 #0: ffff0000105e9998 (&nbd->config_lock){+.+.}-{3:3}, at: nbd_ioctl+0x108/0x8f0 drivers/block/nbd.c:1504
1 lock held by syz-executor.0/9046:
 #0: ffff0000105e9998 (&nbd->config_lock){+.+.}-{3:3}, at: nbd_ioctl+0x108/0x8f0 drivers/block/nbd.c:1504

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