[v6.1] WARNING in btrfs_quota_enable

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: 8e6e2188d949 Linux 6.1.157
git tree: linux-6.1.y
console output: https://syzkaller.appspot.com/x/log.txt?x=16796704580000
kernel config: https://syzkaller.appspot.com/x/.config?x=68aa5a3af1cb953a
dashboard link: https://syzkaller.appspot.com/bug?extid=9667876a0051d3a7addb
compiler: Debian clang version 20.1.8 (++20250708063551+0c9f909b7976-1~exp1~20250708183702.136), Debian LLD 20.1.8
userspace arch: arm64

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

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/eb7c93b37aac/disk-8e6e2188.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/aab942f8b193/vmlinux-8e6e2188.xz
kernel image: https://storage.googleapis.com/syzbot-assets/c2aae359db05/Image-8e6e2188.gz.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+966787...@syzkaller.appspotmail.com

------------[ cut here ]------------
WARNING: CPU: 1 PID: 6960 at fs/btrfs/qgroup.c:1042 btrfs_quota_enable+0x14a0/0x1a68 fs/btrfs/qgroup.c:1042
Modules linked in:
CPU: 1 PID: 6960 Comm: syz.6.457 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/30/2025
pstate: 62400005 (nZCv daif +PAN -UAO +TCO -DIT -SSBS BTYPE=--)
pc : btrfs_quota_enable+0x14a0/0x1a68 fs/btrfs/qgroup.c:1042
lr : btrfs_quota_enable+0x14a0/0x1a68 fs/btrfs/qgroup.c:1042
sp : ffff800021577a80
x29: ffff800021577c30 x28: 00000000000017d8 x27: ffff800021577b70
x26: dfff800000000000 x25: ffff0000e292e498 x24: ffffffffffffffe4
x23: 1fffe0001c525c9d x22: ffff7000042aef60 x21: ffff0000e292e4e8
x20: 0000000000000000 x19: ffff0000f36b8000 x18: ffff800011abbcc0
x17: 0000000000000000 x16: ffff8000082d25b8 x15: 0000000000000002
x14: 00000000ffffffff x13: 0000000000000001 x12: 0000000000080000
x11: 000000000000f77d x10: ffff80002a42f000 x9 : cd1f360b8ed37b00
x8 : cd1f360b8ed37b00 x7 : 0000000000000001 x6 : 0000000000000001
x5 : ffff800021577518 x4 : ffff8000151a4920 x3 : ffff80000852e428
x2 : 0000000000000001 x1 : 0000000100000000 x0 : 0000000000000000
Call trace:
btrfs_quota_enable+0x14a0/0x1a68 fs/btrfs/qgroup.c:1042
btrfs_ioctl_quota_ctl+0x13c/0x180 fs/btrfs/ioctl.c:4621
btrfs_ioctl+0x9f0/0xbd0 fs/btrfs/ioctl.c:5590
vfs_ioctl fs/ioctl.c:51 [inline]
__do_sys_ioctl fs/ioctl.c:870 [inline]
__se_sys_ioctl fs/ioctl.c:856 [inline]
__arm64_sys_ioctl+0x14c/0x1c8 fs/ioctl.c:856
__invoke_syscall arch/arm64/kernel/syscall.c:38 [inline]
invoke_syscall+0x98/0x2bc arch/arm64/kernel/syscall.c:52
el0_svc_common+0x138/0x258 arch/arm64/kernel/syscall.c:140
do_el0_svc+0x58/0x13c arch/arm64/kernel/syscall.c:204
el0_svc+0x58/0x138 arch/arm64/kernel/entry-common.c:637
el0t_64_sync_handler+0x84/0xf0 arch/arm64/kernel/entry-common.c:655
el0t_64_sync+0x18c/0x190 arch/arm64/kernel/entry.S:585
irq event stamp: 158
hardirqs last enabled at (157): [<ffff8000083086fc>] __up_console_sem+0xb4/0x100 kernel/printk/printk.c:261
hardirqs last disabled at (158): [<ffff80001195c1f0>] el1_dbg+0x24/0x80 arch/arm64/kernel/entry-common.c:405
softirqs last enabled at (8): [<ffff8000080309e0>] local_bh_enable+0x10/0x34 include/linux/bottom_half.h:32
softirqs last disabled at (6): [<ffff8000080309ac>] local_bh_disable+0x10/0x34 include/linux/bottom_half.h:19
---[ end trace 0000000000000000 ]---
BTRFS info (device loop6: state EA): dumping space info:
BTRFS info (device loop6: state EA): space_info DATA+METADATA has 1638400 free, is full
BTRFS info (device loop6: state EA): space_info total=3276800, used=61440, pinned=0, reserved=0, may_use=1576960, readonly=0 zone_unusable=0
BTRFS info (device loop6: state EA): space_info SYSTEM has 8155136 free, is not full
BTRFS info (device loop6: state EA): space_info total=12451840, used=4096, pinned=0, reserved=4096, may_use=98304, readonly=4190208 zone_unusable=0
BTRFS info (device loop6: state EA): global_block_rsv: size 1441792 reserved 1441792
BTRFS info (device loop6: state EA): trans_block_rsv: size 131072 reserved 131072
BTRFS info (device loop6: state EA): chunk_block_rsv: size 98304 reserved 98304
BTRFS info (device loop6: state EA): delayed_block_rsv: size 0 reserved 0
BTRFS info (device loop6: state EA): delayed_refs_rsv: size 393216 reserved 4096
BTRFS: error (device loop6: state EA) in btrfs_quota_enable:1042: errno=-28 No space left


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