ldm_validate_partition_table(): Disk read failed.
Dev nbd4: unable to read RDB block 0
 nbd4: unable to read partition table
ldm_validate_partition_table(): Disk read failed.
Dev nbd4: unable to read RDB block 0
 nbd4: unable to read partition table
BUG: MAX_LOCKDEP_ENTRIES too low!
turning off the locking correctness validator.
CPU: 0 PID: 27468 Comm: systemd-udevd Not tainted 5.12.0-rc7-next-20210413-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 __dump_stack lib/dump_stack.c:79 [inline]
 dump_stack+0x141/0x1d7 lib/dump_stack.c:120
 alloc_list_entry kernel/locking/lockdep.c:1354 [inline]
 add_lock_to_list.constprop.0.cold+0x11/0x18 kernel/locking/lockdep.c:1375
 check_prev_add kernel/locking/lockdep.c:3008 [inline]
 check_prevs_add kernel/locking/lockdep.c:3061 [inline]
 validate_chain kernel/locking/lockdep.c:3676 [inline]
 __lock_acquire+0x2e3a/0x5230 kernel/locking/lockdep.c:4902
 lock_acquire kernel/locking/lockdep.c:5512 [inline]
 lock_acquire+0x1ab/0x740 kernel/locking/lockdep.c:5477
 do_write_seqcount_begin_nested include/linux/seqlock.h:520 [inline]
 do_write_seqcount_begin include/linux/seqlock.h:545 [inline]
 vtime_task_switch_generic+0xb5/0x5a0 kernel/sched/cputime.c:768
 vtime_task_switch include/linux/vtime.h:49 [inline]
 finish_task_switch.isra.0+0x4bd/0x810 kernel/sched/core.c:4197
 context_switch kernel/sched/core.c:4332 [inline]
 __schedule+0x91f/0x2170 kernel/sched/core.c:5079
 preempt_schedule_irq+0x4e/0x90 kernel/sched/core.c:5536
 irqentry_exit_cond_resched kernel/entry/common.c:392 [inline]
 irqentry_exit_cond_resched kernel/entry/common.c:384 [inline]
 irqentry_exit+0x7a/0xa0 kernel/entry/common.c:428
 asm_sysvec_apic_timer_interrupt+0x12/0x20 arch/x86/include/asm/idtentry.h:632
RIP: 0010:lock_acquire+0x1ef/0x740 kernel/locking/lockdep.c:5480
Code: e1 a7 7e 83 f8 01 0f 85 fc 03 00 00 9c 58 f6 c4 02 0f 85 e7 03 00 00 48 83 7c 24 08 00 74 01 fb 48 b8 00 00 00 00 00 fc ff df <48> 01 c3 48 c7 03 00 00 00 00 48 c7 43 08 00 00 00 00 48 8b 84 24
RSP: 0018:ffffc9000c3cf978 EFLAGS: 00000206
RAX: dffffc0000000000 RBX: 1ffff92001879f31 RCX: 0000000000000001
RDX: 1ffff1100dcd513e RSI: 0000000000000000 RDI: 0000000000000000
RBP: 0000000000000001 R08: 00000000001bfee8 R09: 0000000000000001
R10: fffffbfff1f919af R11: 1ffffffff1f263c7 R12: 0000000000000000
R13: ffff8880197f9938 R14: 0000000000000000 R15: 0000000000000000
 flush_workqueue+0x110/0x13e0 kernel/workqueue.c:2786
 drain_workqueue+0x1a5/0x3c0 kernel/workqueue.c:2951
 destroy_workqueue+0x71/0x800 kernel/workqueue.c:4382
 nbd_config_put+0x3d3/0x8f0 drivers/block/nbd.c:1231
 nbd_release+0x112/0x1a0 drivers/block/nbd.c:1506
 __blkdev_put+0x5d4/0x790 fs/block_dev.c:1585
 blkdev_put+0x92/0x580 fs/block_dev.c:1638
 blkdev_close+0x8c/0xb0 fs/block_dev.c:1646
 __fput+0x288/0x920 fs/file_table.c:280
 task_work_run+0xdd/0x1a0 kernel/task_work.c:164
 tracehook_notify_resume include/linux/tracehook.h:189 [inline]
 exit_to_user_mode_loop kernel/entry/common.c:174 [inline]
 exit_to_user_mode_prepare+0x272/0x280 kernel/entry/common.c:208
 __syscall_exit_to_user_mode_work kernel/entry/common.c:290 [inline]
 syscall_exit_to_user_mode+0x19/0x60 kernel/entry/common.c:301
 do_syscall_64+0x47/0xb0 arch/x86/entry/common.c:57
 entry_SYSCALL_64_after_hwframe+0x44/0xae
RIP: 0033:0x7f29419ed270
Code: 73 01 c3 48 8b 0d 38 7d 20 00 f7 d8 64 89 01 48 83 c8 ff c3 66 0f 1f 44 00 00 83 3d 59 c1 20 00 00 75 10 b8 03 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 31 c3 48 83 ec 08 e8 ee fb ff ff 48 89 04 24
RSP: 002b:00007ffd89425dd8 EFLAGS: 00000246 ORIG_RAX: 0000000000000003
RAX: 0000000000000000 RBX: 0000000000000007 RCX: 00007f29419ed270
RDX: 000000000aba9500 RSI: 0000000000000000 RDI: 0000000000000007
RBP: 00007f29428a7710 R08: 000000000000004a R09: 0000000000000008
R10: 000055ac240d7818 R11: 0000000000000246 R12: 0000000000000000
R13: 000055ac240da940 R14: 0000000000000003 R15: 000000000000000e