[syzbot] [btrfs?] WARNING in __btrfs_run_delayed_items (2)

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: 44fc84337b6e Merge tag 'arm64-upstream' of git://git.kerne..
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=113b1192580000
kernel config: https://syzkaller.appspot.com/x/.config?x=e613d5a6bd72b912
dashboard link: https://syzkaller.appspot.com/bug?extid=64c9efba06e7ad505aef
compiler: Debian clang version 20.1.8 (++20250708063551+0c9f909b7976-1~exp1~20250708183702.136), Debian LLD 20.1.8

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-44fc8433.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/62d35c4f6e28/vmlinux-44fc8433.xz
kernel image: https://storage.googleapis.com/syzbot-assets/b8d61aa183d4/bzImage-44fc8433.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+64c9ef...@syzkaller.appspotmail.com

BTRFS error (device loop0): allocation failed flags 4, wanted 4096 tree-log 0, relocation: 0
BTRFS info (device loop0): space_info DATA+METADATA (sub-group id 0) has -1544192 free, is full
BTRFS info (device loop0): space_info total=11534336, used=3231744, pinned=45056, reserved=8257536, may_use=1544192, readonly=0 zone_unusable=0
BTRFS info (device loop0): global_block_rsv: size 1441792 reserved 1441792
BTRFS info (device loop0): trans_block_rsv: size 0 reserved 0
BTRFS info (device loop0): chunk_block_rsv: size 0 reserved 0
BTRFS info (device loop0): delayed_block_rsv: size 98304 reserved 94208
BTRFS info (device loop0): delayed_refs_rsv: size 0 reserved 0
BTRFS info (device loop0): block group 5242880 has 1638400 bytes, 1593344 used 45056 pinned 0 reserved 0 delalloc 0 super 0 zone_unusable (0 bytes available)
BTRFS info (device loop0): block group has cluster?: no
BTRFS info (device loop0): 0 free space entries at or bigger than 4096 bytes
BTRFS info (device loop0): block group 6881280 has 1638400 bytes, 1638400 used 0 pinned 0 reserved 0 delalloc 0 super 0 zone_unusable (0 bytes available)
BTRFS info (device loop0): block group has cluster?: no
BTRFS info (device loop0): 0 free space entries at or bigger than 4096 bytes
BTRFS info (device loop0): block group 8519680 has 8257536 bytes, 0 used 0 pinned 0 reserved 0 delalloc 0 super 0 zone_unusable (8257536 bytes available)
BTRFS critical (device loop0): entry offset 8519680, bytes 8257536, bitmap no
BTRFS info (device loop0): block group has cluster?: no
BTRFS info (device loop0): 1 free space entries at or bigger than 4096 bytes
BTRFS info (device loop0): 8257536 bytes available across all block groups
------------[ cut here ]------------
BTRFS: Transaction aborted (error -28)
WARNING: fs/btrfs/delayed-inode.c:1179 at 0x0, CPU#0: kworker/u4:24/4375
Modules linked in:
CPU: 0 UID: 0 PID: 4375 Comm: kworker/u4:24 Not tainted syzkaller #0 PREEMPT(full)
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2~bpo12+1 04/01/2014
Workqueue: events_unbound btrfs_async_reclaim_data_space
RIP: 0010:__btrfs_run_delayed_items+0x46c/0x540 fs/btrfs/delayed-inode.c:1179
Code: 85 f6 75 07 e8 d5 c4 da fd eb 7a e8 ee b4 c0 fd 84 c0 74 20 e8 c5 c4 da fd eb 6a e8 be c4 da fd 48 8d 3d 97 0f a3 0b 44 89 e6 <67> 48 0f b9 3a e9 da fe ff ff e8 75 1e 62 07 41 89 c6 31 ff 89 c6
RSP: 0018:ffffc9000e887470 EFLAGS: 00010293
RAX: ffffffff83e64972 RBX: ffff888053d72630 RCX: ffff888033358000
RDX: 0000000000000000 RSI: 00000000ffffffe4 RDI: ffffffff8f895910
RBP: 0000000000000000 R08: ffff888033358000 R09: 0000000000000003
R10: 00000000fffffffb R11: 0000000000000000 R12: 00000000ffffffe4
R13: ffff888053c953d0 R14: ffff888052b70001 R15: 1ffff1100a7ae4c6
FS: 0000000000000000(0000) GS:ffff88808d6b7000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000020000037d000 CR3: 0000000042677000 CR4: 0000000000352ef0
Call Trace:
<TASK>
btrfs_commit_transaction+0x865/0x3950 fs/btrfs/transaction.c:2325
flush_space+0x48b/0xcb0 fs/btrfs/space-info.c:888
do_async_reclaim_data_space+0x2a6/0x520 fs/btrfs/space-info.c:1410
btrfs_async_reclaim_data_space+0x41/0x90 fs/btrfs/space-info.c:1458
process_one_work kernel/workqueue.c:3263 [inline]
process_scheduled_works+0xad1/0x1770 kernel/workqueue.c:3346
worker_thread+0x8a0/0xda0 kernel/workqueue.c:3427
kthread+0x711/0x8a0 kernel/kthread.c:463
ret_from_fork+0x599/0xb30 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246
</TASK>
----------------
Code disassembly (best guess):
0: 85 f6 test %esi,%esi
2: 75 07 jne 0xb
4: e8 d5 c4 da fd call 0xfddac4de
9: eb 7a jmp 0x85
b: e8 ee b4 c0 fd call 0xfdc0b4fe
10: 84 c0 test %al,%al
12: 74 20 je 0x34
14: e8 c5 c4 da fd call 0xfddac4de
19: eb 6a jmp 0x85
1b: e8 be c4 da fd call 0xfddac4de
20: 48 8d 3d 97 0f a3 0b lea 0xba30f97(%rip),%rdi # 0xba30fbe
27: 44 89 e6 mov %r12d,%esi
* 2a: 67 48 0f b9 3a ud1 (%edx),%rdi <-- trapping instruction
2f: e9 da fe ff ff jmp 0xffffff0e
34: e8 75 1e 62 07 call 0x7621eae
39: 41 89 c6 mov %eax,%r14d
3c: 31 ff xor %edi,%edi
3e: 89 c6 mov %eax,%esi


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