WARNING in corrupted (2)

[syzbot]

Hello,

syzbot found the following crash on:

HEAD commit:    a6ed68d6 Merge tag 'drm-next-2019-11-27' of git://anongit...
git tree:       upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=173ab832e00000
kernel config:  https://syzkaller.appspot.com/x/.config?x=6349516b24252b37
dashboard link: https://syzkaller.appspot.com/bug?extid=c792a994cd965b2ac623
compiler:       gcc (GCC) 9.0.0 20181231 (experimental)
userspace arch: i386
syz repro:      https://syzkaller.appspot.com/x/repro.syz?x=106bdb86e00000

IMPORTANT: if you fix the bug, please add the following tag to the commit:
Reported-by: syzbot+c792a994cd965b2ac623@xxxxxxxxxxxxxxxxxxxxxxxxx

------------[ cut here ]------------
generic_make_request: Trying to write to read-only block-device loop0  
(partno 0)
WARNING: CPU: 1 PID: 8854 at block/blk-core.c:800 bio_check_ro  
block/blk-core.c:800 [inline]
WARNING: CPU: 1 PID: 8854 at block/blk-core.c:800  
generic_make_request_checks+0x1c78/0x2190 block/blk-core.c:901
Kernel panic - not syncing: panic_on_warn set ...
CPU: 1 PID: 8854 Comm: blkid Not tainted 5.4.0-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS  
Google 01/01/2011


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