From: syzbot <syzbot+9ca2c6e6b098bf5ae60a@syzkaller.appspotmail.com>
To: brauner@kernel.org, jack@suse.cz, kees@kernel.org,
linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org,
linux-mm@kvack.org, syzkaller-bugs@googlegroups.com,
viro@zeniv.linux.org.uk
Subject: Re: [syzbot] [fs?] [mm?] WARNING in sched_mm_cid_fork
Date: Thu, 11 Dec 2025 16:25:25 -0800 [thread overview]
Message-ID: <693b60f5.050a0220.4004e.04c5.GAE@google.com> (raw)
In-Reply-To: <692fc776.a70a0220.2ea503.00cb.GAE@google.com>
syzbot has found a reproducer for the following issue on:
HEAD commit: d358e5254674 Merge tag 'for-6.19/dm-changes' of git://git...
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=11c0d1c2580000
kernel config: https://syzkaller.appspot.com/x/.config?x=de48dccdf203ea90
dashboard link: https://syzkaller.appspot.com/bug?extid=9ca2c6e6b098bf5ae60a
compiler: Debian clang version 20.1.8 (++20250708063551+0c9f909b7976-1~exp1~20250708183702.136), Debian LLD 20.1.8
syz repro: https://syzkaller.appspot.com/x/repro.syz?x=144621b4580000
C reproducer: https://syzkaller.appspot.com/x/repro.c?x=124621b4580000
Downloadable assets:
disk image (non-bootable): https://storage.googleapis.com/syzbot-assets/d900f083ada3/non_bootable_disk-d358e525.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/3fa1d04c1a85/vmlinux-d358e525.xz
kernel image: https://storage.googleapis.com/syzbot-assets/a9b253146e36/bzImage-d358e525.xz
mounted in repro: https://storage.googleapis.com/syzbot-assets/4a5df3575982/mount_1.gz
fsck result: OK (log: https://syzkaller.appspot.com/x/fsck.log?x=11119592580000)
IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+9ca2c6e6b098bf5ae60a@syzkaller.appspotmail.com
------------[ cut here ]------------
WARNING: kernel/sched/core.c:10569 at sched_mm_cid_fork+0x66/0xc30 kernel/sched/core.c:10569, CPU#0: kworker/u4:4/5674
Modules linked in:
CPU: 0 UID: 0 PID: 5674 Comm: kworker/u4:4 Not tainted syzkaller #0 PREEMPT(full)
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2~bpo12+1 04/01/2014
RIP: 0010:sched_mm_cid_fork+0x66/0xc30 kernel/sched/core.c:10569
Code: 4c 8b 3b 4d 85 ff 74 21 49 8d 9d d4 15 00 00 48 89 d8 48 c1 e8 03 42 0f b6 04 30 84 c0 0f 85 13 0a 00 00 31 c0 3b 03 70 04 90 <0f> 0b 90 49 8d 9f 00 01 00 00 49 8d bf c0 01 00 00 48 89 7c 24 20
RSP: 0000:ffffc900036cfbd8 EFLAGS: 00010246
RAX: 1ffff110067b79e3 RBX: ffff888033dbcf18 RCX: ffff888033dbc980
RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffff888033dbc980
RBP: ffffc900036cfd68 R08: ffffffff8e295e83 R09: 1ffffffff1c52bd0
R10: dffffc0000000000 R11: fffffbfff1c52bd1 R12: ffff888033dbc980
R13: ffff888033dbc980 R14: dffffc0000000000 R15: 0000000000000000
FS: 0000000000000000(0000) GS:ffff88808d22f000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f6ad913e000 CR3: 0000000041a50000 CR4: 0000000000352ef0
Call Trace:
<TASK>
bprm_execve+0xd88/0x1400 fs/exec.c:1776
kernel_execve+0x8f0/0x9f0 fs/exec.c:1919
call_usermodehelper_exec_async+0x210/0x360 kernel/umh.c:109
ret_from_fork+0x599/0xb30 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246
</TASK>
---
If you want syzbot to run the reproducer, reply with:
#syz test: git://repo/address.git branch-or-commit-hash
If you attach or paste a git patch, syzbot will apply it before testing.
prev parent reply other threads:[~2025-12-12 0:25 UTC|newest]
Thread overview: 2+ messages / expand[flat|nested] mbox.gz Atom feed top
2025-12-03 5:15 syzbot
2025-12-12 0:25 ` syzbot [this message]
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=693b60f5.050a0220.4004e.04c5.GAE@google.com \
--to=syzbot+9ca2c6e6b098bf5ae60a@syzkaller.appspotmail.com \
--cc=brauner@kernel.org \
--cc=jack@suse.cz \
--cc=kees@kernel.org \
--cc=linux-fsdevel@vger.kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-mm@kvack.org \
--cc=syzkaller-bugs@googlegroups.com \
--cc=viro@zeniv.linux.org.uk \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox