------------[ cut here ]------------
Trying to write to read-only block-device loop0 (partno 0)
WARNING: CPU: 1 PID: 97 at block/blk-core.c:704 bio_check_ro block/blk-core.c:704 [inline]
WARNING: CPU: 1 PID: 97 at block/blk-core.c:704 submit_bio_checks+0x165c/0x1aa0 block/blk-core.c:817
Modules linked in:
CPU: 1 PID: 97 Comm: kworker/u4:2 Not tainted 5.13.0-rc6-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Workqueue: writeback wb_workfn (flush-7:0)
RIP: 0010:bio_check_ro block/blk-core.c:704 [inline]
RIP: 0010:submit_bio_checks+0x165c/0x1aa0 block/blk-core.c:817
Code: 00 00 45 0f b6 a4 24 e0 05 00 00 48 8d 74 24 60 48 89 ef e8 76 42 fe ff 48 c7 c7 60 52 c0 89 48 89 c6 44 89 e2 e8 49 62 1c 05 <0f> 0b e9 36 f3 ff ff e8 18 e9 ba fd 0f 0b e9 bf f1 ff ff e8 0c e9
RSP: 0018:ffffc900011870a8 EFLAGS: 00010286
RAX: 0000000000000000 RBX: ffff88801f029120 RCX: 0000000000000000
RDX: ffff8880157ac200 RSI: ffffffff815c1755 RDI: fffff52000230e07
RBP: ffff888021885e00 R08: 0000000000000000 R09: 0000000000000000
R10: ffffffff815bb58e R11: 0000000000000000 R12: 0000000000000000
R13: ffff888021885e10 R14: ffff88801b5a9040 R15: ffff88801f029624
FS:  0000000000000000(0000) GS:ffff8880b9d00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fc8026d7718 CR3: 00000000305d1000 CR4: 00000000001506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 submit_bio_noacct+0x81/0xf20 block/blk-core.c:1032
 submit_bio+0x263/0x5e0 block/blk-core.c:1118
 submit_bh_wbc+0x5eb/0x7f0 fs/buffer.c:3075
 __block_write_full_page+0x86c/0x1340 fs/buffer.c:1830
 block_write_full_page+0x14d/0x190 fs/buffer.c:3001
 __writepage+0x60/0x180 mm/page-writeback.c:2311
 write_cache_pages+0x759/0x11a0 mm/page-writeback.c:2246
 generic_writepages mm/page-writeback.c:2337 [inline]
 generic_writepages+0xe2/0x150 mm/page-writeback.c:2326
 do_writepages+0xec/0x290 mm/page-writeback.c:2352
 __writeback_single_inode+0x126/0xfd0 fs/fs-writeback.c:1467
 writeback_sb_inodes+0x53d/0xef0 fs/fs-writeback.c:1732
 __writeback_inodes_wb+0xc6/0x280 fs/fs-writeback.c:1801
 wb_writeback+0x814/0xc40 fs/fs-writeback.c:1907
 wb_check_old_data_flush fs/fs-writeback.c:2009 [inline]
 wb_do_writeback fs/fs-writeback.c:2062 [inline]
 wb_workfn+0x891/0x12d0 fs/fs-writeback.c:2091
 process_one_work+0x98d/0x1600 kernel/workqueue.c:2276
 worker_thread+0x64c/0x1120 kernel/workqueue.c:2422
 kthread+0x3b1/0x4a0 kernel/kthread.c:313
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:294