[syzbot] [ext4?] WARNING in ext4_write_inode (4)

[syzbot <syzbot+77d4c409352d8b3a015e@syzkaller.appspotmail.com>]

Hello,

syzbot found the following issue on:

HEAD commit:    5dd1818b15d9 Merge tag 'for-next-keys-v7.3-rc4' of git://g..
git tree:       upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=150017f9580000
kernel config:  https://syzkaller.appspot.com/x/.config?x=c3bddd52b22c2498
dashboard link: https://syzkaller.appspot.com/bug?extid=77d4c409352d8b3a015e
compiler:       Debian clang version 22.1.8 (++20260613092233+e80beda6e255-1~exp1~20260613092250.77), 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-5dd1818b.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/fa126b13cb66/vmlinux-5dd1818b.xz
kernel image: https://storage.googleapis.com/syzbot-assets/e10c187acaf6/bzImage-5dd1818b.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+77d4c409352d8b3a015e@syzkaller.appspotmail.com

------------[ cut here ]------------
current->flags & PF_MEMALLOC
WARNING: fs/ext4/inode.c:5879 at ext4_write_inode+0x2af/0x350 fs/ext4/inode.c:5879, CPU#0: kswapd0/77
Modules linked in:
CPU: 0 UID: 0 PID: 77 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:ext4_write_inode+0x2af/0x350 fs/ext4/inode.c:5879
Code: 83 c4 18 5b 41 5c 41 5d 41 5e 41 5f 5d c3 cc cc cc cc cc e8 e3 9d 34 ff e8 fe 78 9f fe bd fb ff ff ff eb d9 e8 d2 9d 34 ff 90 <0f> 0b 90 eb ce e8 c7 9d 34 ff bd fb ff ff ff eb c2 e8 bb 9d 34 ff
RSP: 0018:ffffc90000af6ef0 EFLAGS: 00010293
RAX: ffffffff829345be RBX: dffffc0000000000 RCX: ffff88801d340000
RDX: 0000000000000000 RSI: 0000000000000800 RDI: 0000000000000000
RBP: 0000000000000000 R08: ffffffff907a667f R09: 1ffffffff20f4ccf
R10: dffffc0000000000 R11: ffffffff82934310 R12: ffff88801d34002c
R13: ffff8880520aaf90 R14: 0000000000000800 R15: ffff88801d340000
FS:  0000000000000000(0000) GS:ffff88808c2c3000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fa506dff000 CR3: 000000000eb48000 CR4: 0000000000352ef0
Call Trace:
 <TASK>
 write_inode fs/fs-writeback.c:1608 [inline]
 __writeback_single_inode+0x69d/0x1220 fs/fs-writeback.c:1851
 writeback_single_inode+0x544/0xf70 fs/fs-writeback.c:1926
 write_inode_now+0x1c2/0x290 fs/fs-writeback.c:3080
 iput_final fs/inode.c:2005 [inline]
 iput+0x98b/0xf00 fs/inode.c:2064
 dentry_kill+0x1b9/0x880 fs/dcache.c:826
 shrink_kill fs/dcache.c:1275 [inline]
 shrink_dentry_list+0x209/0x310 fs/dcache.c:1292
 prune_dcache_sb+0x119/0x180 fs/dcache.c:1374
 super_cache_scan+0x35f/0x4a0 fs/super.c:225
 do_shrink_slab+0x6d0/0x10e0 mm/shrinker.c:445
 shrink_slab_memcg mm/shrinker.c:562 [inline]
 shrink_slab+0x838/0x1220 mm/shrinker.c:640
 shrink_one+0x2a2/0x730 mm/vmscan.c:5119
 shrink_many mm/vmscan.c:5180 [inline]
 lru_gen_shrink_node mm/vmscan.c:5258 [inline]
 shrink_node+0x35d0/0x3e30 mm/vmscan.c:6247
 kswapd_shrink_node mm/vmscan.c:7101 [inline]
 balance_pgdat mm/vmscan.c:7279 [inline]
 kswapd+0x185e/0x32c0 mm/vmscan.c:7555
 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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