WARNING in __blkdev_put (2)

[syzbot]

Hello,

syzbot found the following crash on:

HEAD commit:    dcb8cfbd Merge tag 'for-linus-5.3a-rc3-tag' of git://git.k..
git tree:       upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=1478050c600000
kernel config:  https://syzkaller.appspot.com/x/.config?x=4c7b914a2680c9c6
dashboard link: https://syzkaller.appspot.com/bug?extid=34a8ffb71f7fb32ecca2
compiler:       gcc (GCC) 9.0.0 20181231 (experimental)
syz repro:      https://syzkaller.appspot.com/x/repro.syz?x=17190230600000

IMPORTANT: if you fix the bug, please add the following tag to the commit:
Reported-by: syzbot+34a8ffb71f7fb32ecca2@xxxxxxxxxxxxxxxxxxxxxxxxx

8021q: adding VLAN 0 to HW filter on device batadv0
WARNING: CPU: 1 PID: 10201 at fs/block_dev.c:1899 __blkdev_put+0x6ba/0x810  
fs/block_dev.c:1899
Kernel panic - not syncing: panic_on_warn set ...
CPU: 1 PID: 10201 Comm: syz-executor.0 Not tainted 5.3.0-rc2+ #114
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS  
Google 01/01/2011
Call Trace:
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack+0x172/0x1f0 lib/dump_stack.c:113
 panic+0x2dc/0x755 kernel/panic.c:219
 __warn.cold+0x20/0x4c kernel/panic.c:576
 report_bug+0x263/0x2b0 lib/bug.c:186
 fixup_bug arch/x86/kernel/traps.c:179 [inline]
 fixup_bug arch/x86/kernel/traps.c:174 [inline]
 do_error_trap+0x11b/0x200 arch/x86/kernel/traps.c:272
 do_invalid_op+0x37/0x50 arch/x86/kernel/traps.c:291
 invalid_op+0x23/0x30 arch/x86/entry/entry_64.S:1026
RIP: 0010:__blkdev_put+0x6ba/0x810 fs/block_dev.c:1899
Code: 00 00 00 fc ff df 48 c1 ea 03 80 3c 02 00 0f 84 24 fd ff ff 48 8b bd  
50 ff ff ff e8 90 75 e6 ff e9 13 fd ff ff e8 56 5e ac ff <0f> 0b e9 dc fa  
ff ff 48 89 cf e8 57 75 e6 ff e9 6a fa ff ff 48 8b
RSP: 0018:ffff888094a87c90 EFLAGS: 00010293
RAX: ffff888091ccc2c0 RBX: ffff8880a3182740 RCX: ffffffff81c63be4
RDX: 0000000000000000 RSI: ffffffff81c6410a RDI: 0000000000000005
RBP: ffff888094a87d88 R08: ffff888091ccc2c0 R09: ffffed10146304ec
R10: ffff888094a87c80 R11: ffff8880a318275f R12: 0000000000000002
R13: dffffc0000000000 R14: ffff8880a3182758 R15: ffff8880a3182758
 blkdev_put+0x98/0x560 fs/block_dev.c:1969
 blkdev_close+0x8b/0xb0 fs/block_dev.c:1976
 __fput+0x2ff/0x890 fs/file_table.c:280
 ____fput+0x16/0x20 fs/file_table.c:313
 task_work_run+0x145/0x1c0 kernel/task_work.c:113
 tracehook_notify_resume include/linux/tracehook.h:188 [inline]
 exit_to_usermode_loop+0x316/0x380 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+0x5a9/0x6a0 arch/x86/entry/common.c:299
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x4134f0
Code: 01 f0 ff ff 0f 83 30 1b 00 00 c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f  
44 00 00 83 3d 9d 2d 66 00 00 75 14 b8 03 00 00 00 0f 05 <48> 3d 01 f0 ff  
ff 0f 83 04 1b 00 00 c3 48 83 ec 08 e8 0a fc ff ff
RSP: 002b:00007fffd29519c8 EFLAGS: 00000246 ORIG_RAX: 0000000000000003
RAX: 0000000000000000 RBX: 0000000000000003 RCX: 00000000004134f0
RDX: 0000000000000000 RSI: 0000000000004c01 RDI: 0000000000000003
RBP: 00000000007104e0 R08: 0000000000000000 R09: 000000000000000a
R10: 0000000000000075 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fffd2951a00 R14: 0000000000000003 R15: 00007fffd2951a10
Kernel Offset: disabled
Rebooting in 86400 seconds..


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