[syzbot] [btrfs?] WARNING in btrfs_add_link (3)

[syzbot <syzbot+3ae22e13d0d01e5de43c@syzkaller.appspotmail.com>]

Hello,

syzbot found the following issue on:

HEAD commit:    818bebeb63dd drm/xe: Don't hand out the flat CCS storage a..
git tree:       upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=1345d625580000
kernel config:  https://syzkaller.appspot.com/x/.config?x=3c35c7e43de75adb
dashboard link: https://syzkaller.appspot.com/bug?extid=3ae22e13d0d01e5de43c
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-818bebeb.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/9adea981957f/vmlinux-818bebeb.xz
kernel image: https://storage.googleapis.com/syzbot-assets/6676075cd03e/bzImage-818bebeb.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+3ae22e13d0d01e5de43c@syzkaller.appspotmail.com

------------[ cut here ]------------
btrfs_abort_should_print_stack(__error)
WARNING: fs/btrfs/inode.c:6931 at btrfs_add_link+0x932/0xa50 fs/btrfs/inode.c:6931, CPU#0: syz.0.0/5326
Modules linked in:
CPU: 0 UID: 0 PID: 5326 Comm: syz.0.0 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:btrfs_add_link+0x932/0xa50 fs/btrfs/inode.c:6931
Code: e2 74 13 41 83 fe fb 74 14 41 83 fe f4 75 15 e8 84 ca ae fd eb 17 e8 7d ca ae fd eb 10 e8 76 ca ae fd eb 09 e8 6f ca ae fd 90 <0f> 0b 90 44 89 f1 f7 d9 e9 10 fe ff ff 89 df 48 c7 c6 c0 22 3d 8f
RSP: 0018:ffffc900060f74e0 EFLAGS: 00010293
RAX: ffffffff84186a51 RBX: ffff8880517d0001 RCX: ffff88803f6a0000
RDX: 0000000000000000 RSI: ffffffff8f3d2260 RDI: 00000000ffffffe4
RBP: ffffc900060f7610 R08: ffff88803f6a0000 R09: 0000000000000003
R10: 00000000fffffffb R11: 0000000000000000 R12: 1ffff110026d8a64
R13: 00000000ffffffe4 R14: 00000000ffffffe4 R15: ffff8880136c5320
FS:  00007f42d43c66c0(0000) GS:ffff88808c30a000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00005619effb5348 CR3: 000000001287b000 CR4: 0000000000352ef0
Call Trace:
 <TASK>
 btrfs_create_new_inode+0x14a1/0x1ee0 fs/btrfs/inode.c:6864
 btrfs_create_common+0x189/0x310 fs/btrfs/inode.c:6990
 lookup_open+0xc0d/0x1a40 fs/namei.c:4567
 open_last_lookups fs/namei.c:4767 [inline]
 path_openat+0x677/0x1d60 fs/namei.c:4997
 do_file_open+0x23e/0x4a0 fs/namei.c:5029
 do_sys_openat2+0x115/0x200 fs/open.c:1417
 do_sys_open fs/open.c:1423 [inline]
 __do_sys_openat fs/open.c:1439 [inline]
 __se_sys_openat fs/open.c:1434 [inline]
 __x64_sys_openat+0x138/0x170 fs/open.c:1434
 do_syscall_x64 arch/x86/entry/syscall_64.c:61 [inline]
 do_syscall_64+0x166/0x520 arch/x86/entry/syscall_64.c:84
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f42d359e0d9
Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 e8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f42d43c5fe8 EFLAGS: 00000246 ORIG_RAX: 0000000000000101
RAX: ffffffffffffffda RBX: 00007f42d3826090 RCX: 00007f42d359e0d9
RDX: 000000000000275a RSI: 0000200000000040 RDI: ffffffffffffff9c
RBP: 00007f42d3635024 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f42d3826128 R14: 00007f42d3826090 R15: 00007ffc09ee04b8
 </TASK>


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