------------[ cut here ]------------
Trying to write to read-only block-device loop4 (partno 0)
WARNING: CPU: 1 PID: 595 at block/blk-core.c:705 bio_check_ro block/blk-core.c:705 [inline]
WARNING: CPU: 1 PID: 595 at block/blk-core.c:705 submit_bio_checks+0x14db/0x18d0 block/blk-core.c:833
Modules linked in:
CPU: 1 PID: 595 Comm: kworker/u4:9 Not tainted 5.10.45 #1
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.14.0-0-g155821a1990b-prebuilt.qemu.org 04/01/2014
Workqueue: writeback wb_workfn (flush-7:4)
RIP: 0010:bio_check_ro block/blk-core.c:705 [inline]
RIP: 0010:submit_bio_checks+0x14db/0x18d0 block/blk-core.c:833
Code: 03 00 00 45 8b a4 24 64 05 00 00 48 89 ef 48 8d 74 24 50 e8 47 37 fe ff 48 c7 c7 e0 4d 3a 84 48 89 c6 44 89 e2 e8 f5 2d d3 01 <0f> 0b 48 b8 00 00 00 00 00 fc ff df 4c 89 fa 48 c1 ea 03 80 3c 02
RSP: 0018:ffff88804268f118 EFLAGS: 00010282
RAX: 0000000000000000 RBX: 1ffff110084d1e29 RCX: 0000000000000000
RDX: ffff888015b9e500 RSI: ffffffff812943f3 RDI: ffffed10084d1e15
RBP: ffff88800e863900 R08: 0000000000000001 R09: ffff88806cf2facf
R10: 0000000000000000 R11: 0000000000000001 R12: 0000000000000000
R13: ffff88800d8b5470 R14: ffff88800e863910 R15: ffff88800e863908
FS:  0000000000000000(0000) GS:ffff88806cf00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00005638ec977ff8 CR3: 0000000040c96000 CR4: 0000000000350ee0
Call Trace:
 submit_bio_noacct+0x7a/0xce0 block/blk-core.c:1045
 submit_bio+0xf3/0x4e0 block/blk-core.c:1130
 submit_bh_wbc.constprop.0+0x580/0x770 fs/buffer.c:3054
 __block_write_full_page+0x7d3/0x1050 fs/buffer.c:1810
 block_write_full_page+0x21c/0x290 fs/buffer.c:2980
 __writepage+0x67/0x180 mm/page-writeback.c:2311
 write_cache_pages+0x57f/0xef0 mm/page-writeback.c:2246
 generic_writepages mm/page-writeback.c:2337 [inline]
 generic_writepages+0xe2/0x150 mm/page-writeback.c:2326
 do_writepages+0xee/0x290 mm/page-writeback.c:2352
 __writeback_single_inode+0x10a/0xd70 fs/fs-writeback.c:1461
 writeback_sb_inodes+0x56e/0xfc0 fs/fs-writeback.c:1723
 __writeback_inodes_wb+0xbe/0x270 fs/fs-writeback.c:1792
 wb_writeback+0x710/0xaa0 fs/fs-writeback.c:1898
 wb_check_old_data_flush fs/fs-writeback.c:2000 [inline]
 wb_do_writeback fs/fs-writeback.c:2053 [inline]
 wb_workfn+0x7d1/0x1000 fs/fs-writeback.c:2082
 process_one_work+0x9a9/0x1590 kernel/workqueue.c:2270
 worker_thread+0x61d/0x1310 kernel/workqueue.c:2416
 kthread+0x38f/0x470 kernel/kthread.c:292
 ret_from_fork+0x22/0x30 arch/x86/entry/entry_64.S:296
irq event stamp: 399007
hardirqs last  enabled at (399017): [<ffffffff81290989>] console_unlock+0x929/0xb30 kernel/printk/printk.c:2552
hardirqs last disabled at (399024): [<ffffffff81290895>] console_unlock+0x835/0xb30 kernel/printk/printk.c:2467
softirqs last  enabled at (398442): [<ffffffff83e00f92>] asm_call_irq_on_stack+0x12/0x20
softirqs last disabled at (398437): [<ffffffff83e00f92>] asm_call_irq_on_stack+0x12/0x20
---[ end trace 8eb13afe6c18b4af ]---