[syzbot] [trace?] WARNING in ring_buffer_map_get_reader (2)

[syzbot <syzbot+c7143161d8215214a993@syzkaller.appspotmail.com>]

Hello,

syzbot found the following issue on:

HEAD commit:    b6151c4e60e5 Merge tag 'erofs-for-6.19-rc5-fixes' of git:/..
git tree:       upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=14b8f19a580000
kernel config:  https://syzkaller.appspot.com/x/.config?x=ae589cd0a6acd9be
dashboard link: https://syzkaller.appspot.com/bug?extid=c7143161d8215214a993
compiler:       gcc (Debian 12.2.0-14+deb12u1) 12.2.0, 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/fa89172b8626/disk-b6151c4e.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/19077b87b7b3/vmlinux-b6151c4e.xz
kernel image: https://storage.googleapis.com/syzbot-assets/6793df315bec/bzImage-b6151c4e.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+c7143161d8215214a993@syzkaller.appspotmail.com

------------[ cut here ]------------
WARNING: kernel/trace/ring_buffer.c:7363 at ring_buffer_map_get_reader+0x689/0x8d0 kernel/trace/ring_buffer.c:7363, CPU#0: syz.3.3873/24523
Modules linked in:
CPU: 0 UID: 0 PID: 24523 Comm: syz.3.3873 Tainted: G             L      syzkaller #0 PREEMPT(full) 
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
RIP: 0010:ring_buffer_map_get_reader+0x689/0x8d0 kernel/trace/ring_buffer.c:7363
Code: 02 00 00 49 8b 0c 24 8b 74 24 44 4c 89 ea 48 c7 c7 00 6c 93 8b e8 37 5f d9 ff e9 e6 fe ff ff 4c 8b 64 24 60 e8 f8 b3 fb ff 90 <0f> 0b 90 e8 ef b3 fb ff 48 89 df 31 db e8 c5 f9 fd ff 48 8b 74 24
RSP: 0018:ffffc9000bad7db0 EFLAGS: 00010087
RAX: 0000000000000790 RBX: ffff88813ff68800 RCX: ffffc9000eff9000
RDX: 0000000000080000 RSI: ffffffff81c2b728 RDI: 0000000000000007
RBP: dffffc0000000000 R08: 0000000000000007 R09: 0000000000000000
R10: 0000000000000000 R11: ffff88813ff688b0 R12: ffff88813ff68990
R13: 0000000000000000 R14: ffff88813ff688a8 R15: ffff88813ff688b0
FS:  00007f7297ae16c0(0000) GS:ffff8881248fa000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000001b2f7d9ff8 CR3: 0000000087a78000 CR4: 00000000003526f0
Call Trace:
 <TASK>
 tracing_buffers_ioctl+0x2ab/0x360 kernel/trace/trace.c:8938
 vfs_ioctl fs/ioctl.c:51 [inline]
 __do_sys_ioctl fs/ioctl.c:597 [inline]
 __se_sys_ioctl fs/ioctl.c:583 [inline]
 __x64_sys_ioctl+0x18e/0x210 fs/ioctl.c:583
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xcd/0xf80 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f7296b8f7c9
Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 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 a8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f7297ae1038 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00007f7296de6090 RCX: 00007f7296b8f7c9
RDX: 0000000000000000 RSI: 0000000000005220 RDI: 0000000000000006
RBP: 00007f7296c13f91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f7296de6128 R14: 00007f7296de6090 R15: 00007ffcb9ff62d8
 </TASK>


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