loop1: p1
WARNING: CPU: 1 PID: 31385 at fs/block_dev.c:1788 __blkdev_put+0x688/0x830 fs/block_dev.c:1788
kobject: 'kvm' (00000000f163315f): kobject_uevent_env
Kernel panic - not syncing: panic_on_warn set ...

CPU: 1 PID: 31385 Comm: syz-executor1 Not tainted 4.19.0-rc7+ #53
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
kobject: 'kvm' (00000000f163315f): fill_kobj_path: path = '/devices/virtual/misc/kvm'
Call Trace:
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack+0x1c4/0x2b4 lib/dump_stack.c:113
 panic+0x238/0x4e7 kernel/panic.c:184
kobject: 'loop3' (00000000bf27f8db): kobject_uevent_env
 __warn.cold.8+0x163/0x1ba kernel/panic.c:536
kobject: 'loop3' (00000000bf27f8db): fill_kobj_path: path = '/devices/virtual/block/loop3'
 report_bug+0x254/0x2d0 lib/bug.c:186
 fixup_bug arch/x86/kernel/traps.c:178 [inline]
 do_error_trap+0x1fc/0x4d0 arch/x86/kernel/traps.c:296
kobject: 'loop4' (0000000028edf1f5): kobject_uevent_env
 do_invalid_op+0x1b/0x20 arch/x86/kernel/traps.c:316
kobject: 'loop4' (0000000028edf1f5): fill_kobj_path: path = '/devices/virtual/block/loop4'
 invalid_op+0x14/0x20 arch/x86/entry/entry_64.S:993
RIP: 0010:__blkdev_put+0x688/0x830 fs/block_dev.c:1788
Code: ff ff ff ba 01 00 00 00 4c 89 e7 e8 92 f9 ff ff e9 79 fd ff ff 48 c7 85 50 ff ff ff 08 00 00 00 e9 7f fb ff ff e8 38 62 9e ff <0f> 0b e9 0e fb ff ff e8 2c 62 9e ff 48 8b bd 48 ff ff ff 48 c7 83
RSP: 0018:ffff88018c36fa38 EFLAGS: 00010216
kobject: 'loop3' (00000000bf27f8db): kobject_uevent_env
RAX: 0000000000040000 RBX: ffff8801d47e5300 RCX: ffffc90003f00000
RDX: 0000000000014e34 RSI: ffffffff81e07358 RDI: 0000000000000005
RBP: ffff88018c36fb30 R08: ffff8801b42165c0 R09: ffffed003a8fca63
R10: ffff88018c36fa28 R11: ffff8801d47e531f R12: ffff8801d47e5304
R13: 0000000000000001 R14: ffff8801d1d87640 R15: ffffffff81e07a40
kobject: 'loop3' (00000000bf27f8db): fill_kobj_path: path = '/devices/virtual/block/loop3'
kobject: 'loop1' (000000006eeebaf9): kobject_uevent_env
 blkdev_put+0x98/0x540 fs/block_dev.c:1858
kobject: 'loop1' (000000006eeebaf9): fill_kobj_path: path = '/devices/virtual/block/loop1'
 blkdev_close+0x8b/0xb0 fs/block_dev.c:1865
 __fput+0x385/0xa30 fs/file_table.c:278
kobject: 'loop1' (000000006eeebaf9): kobject_uevent_env
kobject: 'loop1' (000000006eeebaf9): fill_kobj_path: path = '/devices/virtual/block/loop1'
 ____fput+0x15/0x20 fs/file_table.c:309
 task_work_run+0x1e8/0x2a0 kernel/task_work.c:113
 tracehook_notify_resume include/linux/tracehook.h:193 [inline]
 exit_to_usermode_loop+0x318/0x380 arch/x86/entry/common.c:166
 prepare_exit_to_usermode arch/x86/entry/common.c:197 [inline]
 syscall_return_slowpath arch/x86/entry/common.c:268 [inline]
 do_syscall_64+0x6be/0x820 arch/x86/entry/common.c:293
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x411051
Code: 75 14 b8 03 00 00 00 0f 05 48 3d 01 f0 ff ff 0f 83 34 19 00 00 c3 48 83 ec 08 e8 0a fc ff ff 48 89 04 24 b8 03 00 00 00 0f 05 <48> 8b 3c 24 48 89 c2 e8 53 fc ff ff 48 89 d0 48 83 c4 08 48 3d 01
RSP: 002b:00007fbbdbd44a10 EFLAGS: 00000293 ORIG_RAX: 0000000000000003
RAX: 0000000000000000 RBX: 00007fbbdbd456d4 RCX: 0000000000411051
RDX: 0000000000000000 RSI: 0000000000004c01 RDI: 0000000000000006
RBP: 0000000000000000 R08: 0000000000000000 R09: 000000000000000c
R10: 0000000000000064 R11: 0000000000000293 R12: 0000000000000000
R13: 0000000000000005 R14: 0000000000000006 R15: 0000000000000001
Kernel Offset: disabled
Rebooting in 86400 seconds..