From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-oo2-f7.google.com (mail-oo2-f7.google.com [74.125.231.135]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 60BB72F49F6 for ; Sat, 5 Sep 2026 10:20:30 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=74.125.231.135 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1788603631; cv=none; b=nfzCjHe5hzAhGpmT1cnIXxoObUlv4RAOPNUPOf9G8bDNqcE5WiLI5hxZZunSdGXN1zB9yb76BIoAJxsM6mnx8km+vYf41zS8m7fqCiERmsxxHZpCf3BvRsBOSRdSMUtPZ4+Nw3edDqouwDTk6hC98fE5yr583Fvlne1XKA9L2Ko= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1788603631; c=relaxed/simple; bh=Idlkh55hRaoETuuycgLnH7GVDVp/axxy3xzNgdKbXv8=; h=MIME-Version:Date:Message-ID:Subject:From:To:Content-Type; b=ljrjgFmDWRaG3WCAh+V61bvuCZHGEG8+2W7lx1amlbobrgyURB1CSL/fh2fNPU6XJl8qKJtu6qtgnirNyOMtq+KMM89Q+uUYHk7uhiH+AwMvlPcWO20EALgT4hC/sIKbqG+qvg1nHDBd9xnU9Ogjxbyc8XqFqad1E2Mq7hto/Xc= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=fail (p=none dis=none) header.from=syzkaller.appspotmail.com; spf=pass smtp.mailfrom=M3KW2WVRGUFZ5GODRSRYTGD7.apphosting.bounces.google.com; arc=none smtp.client-ip=74.125.231.135 Authentication-Results: smtp.subspace.kernel.org; dmarc=fail (p=none dis=none) header.from=syzkaller.appspotmail.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=M3KW2WVRGUFZ5GODRSRYTGD7.apphosting.bounces.google.com Received: by mail-oo2-f7.google.com with SMTP id 006d021491bc7-6b1bebb3ae8so494796eaf.1 for ; Sat, 05 Sep 2026 03:20:30 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20251104; t=1788603629; x=1789208429; h=content-type:to:from:subject:message-id:date:mime-version :x-gm-message-state:from:to:cc:subject:date:message-id:reply-to :content-type; bh=jTlvTJJ4fA8El4tFO6YJiCOtiTrCeymc5pubKYwelis=; b=AVSjmZHMK+zo1bORmH6OT21x+dD1bUGzHgSXAUE19AXH4hbdX63ucliwqKcSLPJYVz J2Jc9IQPWI30rwG2TBIY2u63DzGGfeqNenSQdmxKb8sype6w4m1ggbn3g32Kb0rqphBe ZzPu45RlNtFxlDSEAvvqH6e4OZUiMyX6KUoPtMRNbfjMG22fvaA7tGK+MAzP541vZTKw kDq3VDuzbuOnm7HrwOBjS3edAZ4hz7EvsNI0I5+6qF5/+eKpueM0M11fV3pKP98uqgZd p8WiqB2zuU3VMQFkbjILLzNY8Y2I8adbrTUsVzF91NiqiOHiMJulOtfiLFriqYXpUMsn 0Sug== X-Forwarded-Encrypted: i=1; AKwUvBzYziIE5SfThueWIo1TdJdpsj06jGtykj1cyUhCwIUG4ZdFWjewJADX7MV6A0fHK6AF/9BIGt0DZGVux5s=@vger.kernel.org X-Gm-Message-State: AFuF++kEhlZbGm87CYdAalQBvINxlKnAlmSvQFsqegEJ697kGsT5CJ9h sLJpql47NYtSihyXqS0p/yVD+KzWEMsk9VPHgs5MFQV7YRaxDp69W50CaiBz0W/C+7mnTog/609 kVsfvDg7YTOHQtNp0tmV14kXAIiZxTHHxA9TOKUys8IOJvsOZMnVjOkgUVvs= Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-Received: by 2002:a05:6820:168f:b0:6b0:4199:3cc4 with SMTP id 006d021491bc7-6b6fea84e5dmr9121676eaf.27.1788603629283; Sat, 05 Sep 2026 03:20:29 -0700 (PDT) Date: Sat, 05 Sep 2026 03:20:29 -0700 X-Google-Appengine-App-Id: s~syzkaller X-Google-Appengine-App-Id-Alias: syzkaller Message-ID: <6a9beced.a5e650b3.26d8a.000b.GAE@google.com> Subject: [syzbot] [fs?] WARNING in do_new_mount (6) From: syzbot To: brauner@kernel.org, jack@suse.cz, linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org, syzkaller-bugs@googlegroups.com, viro@zeniv.linux.org.uk Content-Type: text/plain; charset="UTF-8" Hello, syzbot found the following issue on: HEAD commit: 654ae5d73c05 Merge tag 'drm-fixes-2026-09-05' of https://g.. git tree: upstream console output: https://syzkaller.appspot.com/x/log.txt?x=143968f9580000 kernel config: https://syzkaller.appspot.com/x/.config?x=b454dc6b1b7acd30 dashboard link: https://syzkaller.appspot.com/bug?extid=2a13ad6914e6fcec716c 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/49c1a99f815b/disk-654ae5d7.raw.xz vmlinux: https://storage.googleapis.com/syzbot-assets/6fcecf1b8c8d/vmlinux-654ae5d7.xz kernel image: https://storage.googleapis.com/syzbot-assets/fa54b23691ca/bzImage-654ae5d7.xz IMPORTANT: if you fix the issue, please add the following tag to the commit: Reported-by: syzbot+2a13ad6914e6fcec716c@syzkaller.appspotmail.com ------------[ cut here ]------------ DEBUG_LOCKS_WARN_ON(rt_mutex_owner(lock) != current) WARNING: kernel/locking/rtmutex_common.h:193 at debug_rt_mutex_unlock kernel/locking/rtmutex_common.h:193 [inline], CPU#0: syz.5.471/9806 WARNING: kernel/locking/rtmutex_common.h:193 at rt_mutex_slowunlock+0x734/0xa30 kernel/locking/rtmutex.c:1432, CPU#0: syz.5.471/9806 Modules linked in: CPU: 0 UID: 0 PID: 9806 Comm: syz.5.471 Not tainted syzkaller #0 PREEMPT_{RT,(full)} Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026 RIP: 0010:debug_rt_mutex_unlock kernel/locking/rtmutex_common.h:193 [inline] RIP: 0010:rt_mutex_slowunlock+0x73b/0xa30 kernel/locking/rtmutex.c:1432 Code: b1 8f 48 c1 e8 03 42 0f b6 04 20 84 c0 0f 85 cf 02 00 00 83 3d 39 5d 5a 04 00 75 13 48 8d 3d 5c 4f 5d 04 48 c7 c6 20 28 6d 8b <67> 48 0f b9 3a 90 e9 cf f9 ff ff 48 8d 3d 53 4f 5d 04 67 48 0f b9 RSP: 0018:ffffc9000620fbc0 EFLAGS: 00010046 RAX: 0000000000000000 RBX: ffff888061d9a9f8 RCX: 0000000000080000 RDX: ffffc9000ddd9000 RSI: ffffffff8b6d2820 RDI: ffffffff8fb4e1f0 RBP: ffffc9000620fcb0 R08: 0000000000000000 R09: 0000000000000000 R10: dffffc0000000000 R11: fffffbfff1f63df9 R12: dffffc0000000000 R13: 1ffff92000c41f80 R14: ffff888061d9a9a8 R15: 0000000000000246 FS: 00007fc0841446c0(0000) GS:ffff888125bd4000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007ffd88506f52 CR3: 000000003a478000 CR4: 00000000003526f0 Call Trace: inode_unlock include/linux/fs.h:1034 [inline] __unlock_mount fs/namespace.c:2808 [inline] unlock_mount fs/namespace.c:2818 [inline] do_new_mount_fc fs/namespace.c:3795 [inline] do_new_mount+0x82d/0xdc0 fs/namespace.c:3848 do_mount fs/namespace.c:4181 [inline] __do_sys_mount fs/namespace.c:4397 [inline] __se_sys_mount+0x31d/0x420 fs/namespace.c:4374 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: 0033:0x7fc085f2e159 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:00007fc084144028 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5 RAX: ffffffffffffffda RBX: 00007fc0861b6180 RCX: 00007fc085f2e159 RDX: 0000200000000080 RSI: 0000200000000040 RDI: 0000000000000000 RBP: 00007fc085fc5024 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007fc0861b6218 R14: 00007fc0861b6180 R15: 00007ffc1374c1d8 ---------------- Code disassembly (best guess): 0: b1 8f mov $0x8f,%cl 2: 48 c1 e8 03 shr $0x3,%rax 6: 42 0f b6 04 20 movzbl (%rax,%r12,1),%eax b: 84 c0 test %al,%al d: 0f 85 cf 02 00 00 jne 0x2e2 13: 83 3d 39 5d 5a 04 00 cmpl $0x0,0x45a5d39(%rip) # 0x45a5d53 1a: 75 13 jne 0x2f 1c: 48 8d 3d 5c 4f 5d 04 lea 0x45d4f5c(%rip),%rdi # 0x45d4f7f 23: 48 c7 c6 20 28 6d 8b mov $0xffffffff8b6d2820,%rsi * 2a: 67 48 0f b9 3a ud1 (%edx),%rdi <-- trapping instruction 2f: 90 nop 30: e9 cf f9 ff ff jmp 0xfffffa04 35: 48 8d 3d 53 4f 5d 04 lea 0x45d4f53(%rip),%rdi # 0x45d4f8f 3c: 67 addr32 3d: 48 rex.W 3e: 0f .byte 0xf 3f: b9 .byte 0xb9 --- This report is generated by a bot. It may contain errors. See https://goo.gl/tpsmEJ for more information about syzbot. syzbot engineers can be reached at syzkaller@googlegroups.com. syzbot will keep track of this issue. See: https://goo.gl/tpsmEJ#status for how to communicate with syzbot. If the report is already addressed, let syzbot know by replying with: #syz fix: exact-commit-title If you want to overwrite report's subsystems, reply with: #syz set subsystems: new-subsystem (See the list of subsystem names on the web dashboard) If the report is a duplicate of another one, reply with: #syz dup: exact-subject-of-another-report If you want to undo deduplication, reply with: #syz undup