[syzbot] [btrfs?] kernel BUG in btrfs_free_fs_info (2)

[syzbot <syzbot+bbbdd6d6efbfc5174561@syzkaller.appspotmail.com>]

Hello,

syzbot found the following issue on:

HEAD commit:    0ad2507d5d93 Linux 6.14-rc3
git tree:       upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=179ae898580000
kernel config:  https://syzkaller.appspot.com/x/.config?x=6cc40dfe827ffb85
dashboard link: https://syzkaller.appspot.com/bug?extid=bbbdd6d6efbfc5174561
compiler:       Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40

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

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/6bb4d4755dce/disk-0ad2507d.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/57594e8f74d9/vmlinux-0ad2507d.xz
kernel image: https://storage.googleapis.com/syzbot-assets/a4f2442a20b1/bzImage-0ad2507d.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+bbbdd6d6efbfc5174561@syzkaller.appspotmail.com

assertion failed: percpu_counter_sum_positive(em_counter) == 0, in fs/btrfs/disk-io.c:1266
------------[ cut here ]------------
kernel BUG at fs/btrfs/disk-io.c:1266!
Oops: invalid opcode: 0000 [#1] PREEMPT SMP KASAN PTI
CPU: 1 UID: 0 PID: 5826 Comm: syz-executor Not tainted 6.14.0-rc3-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 12/27/2024
RIP: 0010:btrfs_free_fs_info+0x35c/0x360 fs/btrfs/disk-io.c:1266
Code: e9 89 00 20 fe e8 74 f4 dc fd 48 c7 c7 80 2a 6c 8c 48 c7 c6 c0 30 6c 8c 48 c7 c2 00 2b 6c 8c b9 f2 04 00 00 e8 75 3e 42 fd 90 <0f> 0b 66 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 66 0f
RSP: 0018:ffffc900041d7d50 EFLAGS: 00010246
RAX: 000000000000005a RBX: 0000000000000004 RCX: 472f5d3ce77a5400
RDX: 0000000000000000 RSI: 0000000080000000 RDI: 0000000000000000
RBP: 0000000000000001 R08: ffffffff81a1102c R09: 1ffff9200083af44
R10: dffffc0000000000 R11: fffff5200083af45 R12: dffffc0000000000
R13: 1ffff11005ec2bc3 R14: ffff88807e594000 R15: ffff88807e595150
FS:  00005555839d1500(0000) GS:ffff8880b8700000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055acae0e8160 CR3: 000000005f838000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 deactivate_locked_super+0xc4/0x130 fs/super.c:473
 cleanup_mnt+0x41f/0x4b0 fs/namespace.c:1413
 task_work_run+0x24f/0x310 kernel/task_work.c:227
 resume_user_mode_work include/linux/resume_user_mode.h:50 [inline]
 exit_to_user_mode_loop kernel/entry/common.c:114 [inline]
 exit_to_user_mode_prepare include/linux/entry-common.h:329 [inline]
 __syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline]
 syscall_exit_to_user_mode+0x13f/0x340 kernel/entry/common.c:218
 do_syscall_64+0x100/0x230 arch/x86/entry/common.c:89
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fbb69b8e117
Code: a8 ff ff ff f7 d8 64 89 01 48 83 c8 ff c3 0f 1f 44 00 00 31 f6 e9 09 00 00 00 66 0f 1f 84 00 00 00 00 00 b8 a6 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 01 c3 48 c7 c2 a8 ff ff ff f7 d8 64 89 02 b8
RSP: 002b:00007ffca0e02598 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6
RAX: 0000000000000000 RBX: 00007fbb69c0e08c RCX: 00007fbb69b8e117
RDX: 0000000000000000 RSI: 0000000000000009 RDI: 00007ffca0e02650
RBP: 00007ffca0e02650 R08: 0000000000000000 R09: 0000000000000000
R10: 00000000ffffffff R11: 0000000000000246 R12: 00007ffca0e036e0
R13: 00007fbb69c0e08c R14: 0000000000010d6a R15: 00007ffca0e03720
 </TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---
RIP: 0010:btrfs_free_fs_info+0x35c/0x360 fs/btrfs/disk-io.c:1266
Code: e9 89 00 20 fe e8 74 f4 dc fd 48 c7 c7 80 2a 6c 8c 48 c7 c6 c0 30 6c 8c 48 c7 c2 00 2b 6c 8c b9 f2 04 00 00 e8 75 3e 42 fd 90 <0f> 0b 66 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 66 0f
RSP: 0018:ffffc900041d7d50 EFLAGS: 00010246
RAX: 000000000000005a RBX: 0000000000000004 RCX: 472f5d3ce77a5400
RDX: 0000000000000000 RSI: 0000000080000000 RDI: 0000000000000000
RBP: 0000000000000001 R08: ffffffff81a1102c R09: 1ffff9200083af44
R10: dffffc0000000000 R11: fffff5200083af45 R12: dffffc0000000000
R13: 1ffff11005ec2bc3 R14: ffff88807e594000 R15: ffff88807e595150
FS:  00005555839d1500(0000) GS:ffff8880b8700000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fae2d970220 CR3: 000000005f838000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400


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