[syzbot] [gfs2?] WARNING in iomap_writepages

[syzbot] [gfs2?] WARNING in iomap_writepages

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit:    d135ab453a74 Merge tag 'backlight-next-7.4' of git://git.k..
git tree:       upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=13d4dee1580000
kernel config:  https://syzkaller.appspot.com/x/.config?x=ca6085a265c4d259
dashboard link: https://syzkaller.appspot.com/bug?extid=5e659793378ad9e06387
compiler:       Debian clang version 22.1.8 (1~deb13u4), Debian LLD 22.1.8

Unfortunately, I don't have any reproducer for this issue yet.

Downloadable assets:
disk image (non-bootable): https://storage.googleapis.com/syzbot-assets/d900f083ada3/non_bootable_disk-d135ab45.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/4dc024e5978e/vmlinux-d135ab45.xz
kernel image: https://storage.googleapis.com/syzbot-assets/1f7c8ddcde45/bzImage-d135ab45.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+5e659793378ad9e06387@syzkaller.appspotmail.com

------------[ cut here ]------------
(current->flags & PF_MEMALLOC)
WARNING: fs/iomap/buffered-io.c:2084 at iomap_writepages+0x29f/0x2d0 fs/iomap/buffered-io.c:2084, CPU#0: kswapd0/82
Modules linked in:
CPU: 0 UID: 0 PID: 82 Comm: kswapd0 Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2 04/01/2014
RIP: 0010:iomap_writepages+0x29f/0x2d0 fs/iomap/buffered-io.c:2084
Code: 00 65 48 8b 0d 8a be 45 12 48 3b 4c 24 60 75 42 48 8d 65 d8 5b 41 5c 41 5d 41 5e 41 5f 5d c3 cc cc cc cc cc e8 f2 ab 4e ff 90 <0f> 0b 90 b8 fb ff ff ff eb ac 44 89 f9 80 e1 07 80 c1 03 38 c1 0f
RSP: 0018:ffffc90000ebe5a0 EFLAGS: 00010293
RAX: ffffffff827a71be RBX: 0000000000000800 RCX: ffff888000300000
RDX: 0000000000000000 RSI: 0000000000000800 RDI: 0000000000000000
RBP: ffffc90000ebe650 R08: ffffc90000ebe70f R09: 0000000000000000
R10: ffffc90000ebe6a0 R11: fffff520001d7ce2 R12: 1ffff920001d7cb8
R13: dffffc0000000000 R14: ffff8880144b0218 R15: ffff88800030002c
FS:  0000000000000000(0000) GS:ffff88808ac1d000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007ffcb345acd0 CR3: 000000001f98a000 CR4: 0000000000352ef0
Call Trace:
 <TASK>
 gfs2_writepages+0x1bb/0x2a0 fs/gfs2/aops.c:175
 do_writepages+0x338/0x560 mm/page-writeback.c:2560
 filemap_writeback mm/filemap.c:387 [inline]
 filemap_fdatawrite_range mm/filemap.c:412 [inline]
 filemap_fdatawrite+0x1e9/0x2f0 mm/filemap.c:418
 gfs2_ordered_write fs/gfs2/log.c:730 [inline]
 __gfs2_log_flush+0x836/0x1d90 fs/gfs2/log.c:1135
 gfs2_log_flush+0x34/0x50 fs/gfs2/log.c:1217
 evict_linked_inode fs/gfs2/super.c:1439 [inline]
 gfs2_evict_inode+0x787/0x13f0 fs/gfs2/super.c:1506
 evict+0x624/0xb50 fs/inode.c:822
 dispose_list fs/inode.c:864 [inline]
 prune_icache_sb+0x223/0x2d0 fs/inode.c:1010
 super_cache_scan+0x390/0x4a0 fs/super.c:227
 do_shrink_slab+0x6d0/0x10d0 mm/shrinker.c:445
 shrink_slab_memcg mm/shrinker.c:562 [inline]
 shrink_slab+0x838/0x1210 mm/shrinker.c:640
 shrink_one+0x396/0x10f0 mm/vmscan.c:5315
 shrink_many mm/vmscan.c:5376 [inline]
 lru_gen_shrink_node mm/vmscan.c:5454 [inline]
 shrink_node+0x631e/0x6b20 mm/vmscan.c:6460
 kswapd_shrink_node mm/vmscan.c:7253 [inline]
 balance_pgdat mm/vmscan.c:7424 [inline]
 kswapd+0x1ff4/0x3a20 mm/vmscan.c:7700
 kthread+0x38b/0x480 kernel/kthread.c:436
 ret_from_fork+0x514/0xb70 arch/x86/kernel/process.c:158
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
 </TASK>


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