EXT4-fs warning (device loop4): ext4_da_update_reserve_space:375: ext4_da_update_reserve_space: ino 18, used 1 with only 0 reserved data blocks
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WARNING: CPU: 0 PID: 3183 at fs/ext4/inode.c:376 ext4_da_update_reserve_space+0x413/0x720 fs/ext4/inode.c:372
Modules linked in:
CPU: 0 PID: 3183 Comm: kworker/u4:1 Not tainted 5.15.107-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/30/2023
Workqueue: writeback wb_workfn (flush-7:4)
RIP: 0010:ext4_da_update_reserve_space+0x413/0x720 fs/ext4/inode.c:376
Code: 4c 89 ff 48 c7 c6 f4 ec 15 8c ba 77 01 00 00 48 c7 c1 c0 da 9b 8a 49 c7 c0 f4 ec 15 8c 41 55 41 54 e8 a1 64 0e 00 48 83 c4 10 <0f> 0b 48 bd 00 00 00 00 00 fc ff df 0f b6 04 2b 84 c0 0f 85 8f 01
RSP: 0018:ffffc90004e56d70 EFLAGS: 00010282
RAX: e76bb5ccdfe47f00 RBX: 1ffff1100e651884 RCX: e76bb5ccdfe47f00
RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000000
RBP: ffff88807328beb0 R08: ffffffff816612ec R09: ffffed10173467a0
R10: 0000000000000000 R11: dffffc0000000001 R12: 0000000000000001
R13: 0000000000000000 R14: ffff88807328be70 R15: ffff8880335b4000
FS:  0000000000000000(0000) GS:ffff8880b9a00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f4fd5c62000 CR3: 000000007e528000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 ext4_map_blocks+0xb3b/0x1e30 fs/ext4/inode.c:666
 mpage_map_one_extent fs/ext4/inode.c:2406 [inline]
 mpage_map_and_submit_extent fs/ext4/inode.c:2459 [inline]
 ext4_writepages+0x160e/0x3d10 fs/ext4/inode.c:2827
 do_writepages+0x481/0x730 mm/page-writeback.c:2364
 __writeback_single_inode+0x15b/0xe30 fs/fs-writeback.c:1622
 writeback_sb_inodes+0xbf0/0x1a50 fs/fs-writeback.c:1905
 wb_writeback+0x451/0xc50 fs/fs-writeback.c:2079
 wb_do_writeback fs/fs-writeback.c:2222 [inline]
 wb_workfn+0x46c/0x1130 fs/fs-writeback.c:2263
 process_one_work+0x8a1/0x10c0 kernel/workqueue.c:2306
 worker_thread+0xaca/0x1280 kernel/workqueue.c:2453
 kthread+0x3f6/0x4f0 kernel/kthread.c:319
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:298
 </TASK>