loop1: p1
 loop3: p1
 loop0: p1
 loop4: p1
 loop5: p1
WARNING: CPU: 1 PID: 3216 at fs/block_dev.c:1899 __blkdev_put+0x59a/0x700 fs/block_dev.c:1923
Kernel panic - not syncing: panic_on_warn set ...
CPU: 1 PID: 3216 Comm: blkid Not tainted 5.3.0-rc3+ #1
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
kobject: 'loop3' (0000000007b5cf03): kobject_uevent_env
Call Trace:
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack+0x113/0x167 lib/dump_stack.c:113
 panic+0x223/0x4ee kernel/panic.c:219
 __warn.cold.10+0x1b/0x45 kernel/panic.c:576
 report_bug+0x1a4/0x200 lib/bug.c:186
 fixup_bug arch/x86/kernel/traps.c:179 [inline]
 do_error_trap+0x11b/0x200 arch/x86/kernel/traps.c:272
 do_invalid_op+0x36/0x40 arch/x86/kernel/traps.c:291
 invalid_op+0x23/0x30 arch/x86/entry/entry_64.S:1028
RIP: 0010:__blkdev_put+0x59a/0x700 fs/block_dev.c:1899
Code: ff ff 8b b5 3c ff ff ff ba 01 00 00 00 4c 89 e7 e8 7b fa ff ff e9 c6 fd ff ff 48 c7 85 50 ff ff ff 08 00 00 00 e9 25 fc ff ff <0f> 0b e9 c3 fb ff ff e8 ea 8a 44 01 48 8b bd 40 ff ff ff e8 be 61
RSP: 0018:ffff8881d8d37cb0 EFLAGS: 00010202
RAX: 0000000000000000 RBX: 1ffff1103b1a6f9f RCX: 0000000000000000
RDX: 0000000000000001 RSI: 0000000000000008 RDI: ffff8881d171c3e8
RBP: ffff8881d8d37da0 R08: ffffed103a2e386c R09: ffffed103a2e386c
R10: ffff8881d8d37ca0 R11: ffff8881d171c35f R12: ffff8881d171c344
R13: 00000000080a101d R14: 00000000080a101d R15: ffff8881d171c340
 blkdev_put+0x73/0x480 fs/block_dev.c:1969
 blkdev_close+0x88/0xd0 fs/block_dev.c:1976
 __fput+0x25d/0x780 fs/file_table.c:280
 ____fput+0x9/0x10 fs/file_table.c:313
 task_work_run+0x10e/0x190 kernel/task_work.c:113
 tracehook_notify_resume include/linux/tracehook.h:188 [inline]
 exit_to_usermode_loop+0x1be/0x210 arch/x86/entry/common.c:163
 prepare_exit_to_usermode arch/x86/entry/common.c:194 [inline]
 syscall_return_slowpath arch/x86/entry/common.c:274 [inline]
 do_syscall_64+0x468/0x550 arch/x86/entry/common.c:299
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x7fd11b1882b0
Code: 40 75 0b 31 c0 48 83 c4 08 e9 0c ff ff ff 48 8d 3d c5 32 08 00 e8 c0 07 02 00 83 3d 45 a3 2b 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 ce 8a 01 00 48 89 04 24
RSP: 002b:00007ffedb9a39a8 EFLAGS: 00000246 ORIG_RAX: 0000000000000003
RAX: 0000000000000000 RBX: 0000000000000000 RCX: 00007fd11b1882b0
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000003
RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000001
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000dd9030
R13: 0000000000000000 R14: 0000000000000003 R15: 0000000000000005
Kernel Offset: disabled
Rebooting in 86400 seconds..