systemd-udevd tasks blocked in the D state while processing the Network Block Devices

Issue

• systemd-udevd tasks were blocked for over 120 seconds in the uninterruptible (UN) state while processing Network Block Devices (nbd*):

systemd-udevd[773]: seq 4793 '/devices/virtual/block/nbd0' is taking a long time
systemd-udevd[773]: seq 4800 '/devices/virtual/block/nbd2' is taking a long time
systemd-udevd[773]: seq 4795 '/devices/virtual/block/nbd1' is taking a long time
systemd-udevd[773]: seq 4802 '/devices/virtual/block/nbd3' is taking a long time
systemd-udevd[773]: seq 4804 '/devices/virtual/block/nbd4' is taking a long time
...
systemd-udevd[773]: seq 4793 '/devices/virtual/block/nbd0' killed
systemd-udevd[773]: seq 4800 '/devices/virtual/block/nbd2' killed
systemd-udevd[773]: seq 4795 '/devices/virtual/block/nbd1' killed
systemd-udevd[773]: seq 4802 '/devices/virtual/block/nbd3' killed
systemd-udevd[773]: seq 4804 '/devices/virtual/block/nbd4' killed
...
kernel: INFO: task systemd-udevd:3912 blocked for more than 120 seconds.
kernel:       Not tainted 4.18.0-553.40.1.el8_10.x86_64 #1
kernel: "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
kernel: task:systemd-udevd   state:D stack:0     pid:3912  ppid:773    flags:0x80000184
kernel: Call Trace:
kernel:  __schedule+0x2d1/0x870
kernel:  schedule+0x55/0xf0
kernel:  schedule_preempt_disabled+0xa/0x10
kernel:  __mutex_lock.isra.11+0x349/0x420
kernel:  nbd_open+0x1a/0x250 [nbd]
kernel:  __blkdev_get+0x83/0x340
kernel:  blkdev_get+0x1a5/0x2d0
kernel:  ? igrab+0x31/0x50
kernel:  ? bd_acquire+0xd0/0xd0
kernel:  do_dentry_open+0x143/0x3a0
kernel:  path_openat+0x55b/0x1580
kernel:  ? __check_object_size+0xac/0x173
kernel:  ? _copy_to_user+0x22/0x40
kernel:  ? move_addr_to_user+0xb2/0xd0
kernel:  do_filp_open+0x93/0x100
kernel:  ? bpf_prog_a30dc2adde086e97_cf_do_filp_open_fentry_1952+0x69/0xc50
kernel:  ? queue_stack_map_push_elem+0x98/0xe0
kernel:  ? bpf_prog_eae87766202680e3_F+0x83/0x330
kernel:  bpf_trampoline_6442490072_3+0x97/0x1000
kernel:  do_filp_open+0x5/0x100
kernel:  do_sys_openat2+0x211/0x2b0
kernel:  do_sys_open+0x4b/0x80
kernel:  do_syscall_64+0x5b/0x1a0
kernel:  entry_SYSCALL_64_after_hwframe+0x66/0xcb
kernel: RIP: 0033:0x7f42519b023f
kernel: Code: Unable to access opcode bytes at RIP 0x7f42519b0215.
kernel: RSP: 002b:00007ffd73509700 EFLAGS: 00000246 ORIG_RAX: 0000000000000101
kernel: RAX: ffffffffffffffda RBX: 000055cecd832f60 RCX: 00007f42519b023f
kernel: RDX: 00000000000a0800 RSI: 000055cecd8524a0 RDI: 00000000ffffff9c
kernel: RBP: 00007ffd73509940 R08: 00007f4252604d60 R09: 000055cecd832010
kernel: R10: 0000000000000000 R11: 0000000000000246 R12: 000055cecd833020
kernel: R13: 000055cecd8462d0 R14: 000055cecd880630 R15: 0000000000000003
...
systemd-udevd[773]: worker [3912] terminated by signal 9 (KILL)
systemd-udevd[773]: worker [3912] failed while handling '/devices/virtual/block/nbd4'