[syzbot] [btrfs?] kernel BUG in radix_tree_tag_set

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: 37e2f878a7a6 Merge tag 'linux_kselftest-kunit-fixes-7.2-rc..
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=13878b46580000
kernel config: https://syzkaller.appspot.com/x/.config?x=98da55a882774dfe
dashboard link: https://syzkaller.appspot.com/bug?extid=edbd404a2566556eed08
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: https://storage.googleapis.com/syzbot-assets/fe4eac79f31b/disk-37e2f878.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/3befde5dfc88/vmlinux-37e2f878.xz
kernel image: https://storage.googleapis.com/syzbot-assets/6e5c89a0b86b/bzImage-37e2f878.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+edbd40...@syzkaller.appspotmail.com

------------[ cut here ]------------
kernel BUG at lib/radix-tree.c:974!
Oops: invalid opcode: 0000 [#1] SMP KASAN PTI
CPU: 0 UID: 0 PID: 1429 Comm: kworker/u8:10 Not tainted syzkaller #0 PREEMPT_{RT,(full)}
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/25/2026
Workqueue: btrfs-endio-write btrfs_work_helper
RIP: 0010:radix_tree_tag_set+0x3ff/0x410 lib/radix-tree.c:974
Code: c7 c7 20 10 96 8f 48 8b 14 24 e8 ac 26 c2 f9 e9 dc fe ff ff e8 12 3b 88 f6 90 0f 0b e8 0a 3b 88 f6 90 0f 0b e8 02 3b 88 f6 90 <0f> 0b 66 66 66 66 66 66 2e 0f 1f 84 00 00 00 00 00 90 90 90 90 90
RSP: 0018:ffffc900063376e0 EFLAGS: 00010293
RAX: ffffffff8b3cfd8e RBX: 0000000000000005 RCX: ffff88802924be00
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: dffffc0000000000 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: ffffffff8e1c3000 R12: ffff88805e3fc188
R13: 1ffff110072500c4 R14: 0000000000000000 R15: ffff888065c981f8
FS: 0000000000000000(0000) GS:ffff888125c49000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f8125d8a6b0 CR3: 0000000053ae4000 CR4: 00000000003526f0
Call Trace:
<TASK>
record_root_in_trans+0x23a/0x330 fs/btrfs/transaction.c:437
btrfs_record_root_in_trans+0x15a/0x180 fs/btrfs/transaction.c:508
start_transaction+0x3a4/0x1880 fs/btrfs/transaction.c:794
btrfs_finish_one_ordered+0x8bb/0x1f00 fs/btrfs/inode.c:3077
btrfs_work_helper+0x338/0xc30 fs/btrfs/async-thread.c:312
process_one_work kernel/workqueue.c:3322 [inline]
process_scheduled_works+0xa8e/0x14e0 kernel/workqueue.c:3405
worker_thread+0xa47/0xfb0 kernel/workqueue.c:3486
kthread+0x388/0x470 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>
Modules linked in:
---[ end trace 0000000000000000 ]---
RIP: 0010:radix_tree_tag_set+0x3ff/0x410 lib/radix-tree.c:974
Code: c7 c7 20 10 96 8f 48 8b 14 24 e8 ac 26 c2 f9 e9 dc fe ff ff e8 12 3b 88 f6 90 0f 0b e8 0a 3b 88 f6 90 0f 0b e8 02 3b 88 f6 90 <0f> 0b 66 66 66 66 66 66 2e 0f 1f 84 00 00 00 00 00 90 90 90 90 90
RSP: 0018:ffffc900063376e0 EFLAGS: 00010293
RAX: ffffffff8b3cfd8e RBX: 0000000000000005 RCX: ffff88802924be00
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: dffffc0000000000 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: ffffffff8e1c3000 R12: ffff88805e3fc188
R13: 1ffff110072500c4 R14: 0000000000000000 R15: ffff888065c981f8
FS: 0000000000000000(0000) GS:ffff888125c49000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f8125d8a6b0 CR3: 0000000053ae4000 CR4: 00000000003526f0


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