linux-kernel - [syzbot] [kernel?] WARNING in sched_change

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Message-ID: <69453b12.a70a0220.207337.010f.GAE@google.com>
Date: Fri, 19 Dec 2025 03:46:26 -0800
From: syzbot <syzbot+90bfe8a4ef62d8d308d1@...kaller.appspotmail.com>
To: andrealmeid@...lia.com, dave@...olabs.net, dvhart@...radead.org, 
	linux-kernel@...r.kernel.org, mingo@...hat.com, peterz@...radead.org, 
	syzkaller-bugs@...glegroups.com, tglx@...utronix.de
Subject: [syzbot] [kernel?] WARNING in sched_change_end

Hello,

syzbot found the following issue on:

HEAD commit:    1058ca9db0ed Add linux-next specific files for 20251218
git tree:       linux-next
console output: https://syzkaller.appspot.com/x/log.txt?x=16fe331a580000
kernel config:  https://syzkaller.appspot.com/x/.config?x=116674f009f72a18
dashboard link: https://syzkaller.appspot.com/bug?extid=90bfe8a4ef62d8d308d1
compiler:       Debian clang version 20.1.8 (++20250708063551+0c9f909b7976-1~exp1~20250708183702.136), Debian LLD 20.1.8

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

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/5ea805477873/disk-1058ca9d.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/df6da7fc6701/vmlinux-1058ca9d.xz
kernel image: https://storage.googleapis.com/syzbot-assets/f20b90dc3994/bzImage-1058ca9d.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+90bfe8a4ef62d8d308d1@...kaller.appspotmail.com

------------[ cut here ]------------
WARNING: kernel/sched/core.c:10852 at sched_change_end+0x4f6/0x640 kernel/sched/core.c:10851, CPU#1: syz.6.795/8435
Modules linked in:
CPU: 1 UID: 0 PID: 8435 Comm: syz.6.795 Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
RIP: 0010:sched_change_end+0x4f6/0x640 kernel/sched/core.c:10851
Code: 00 74 26 48 83 c4 38 5b 41 5c 41 5d 41 5e 41 5f 5d e9 8e 5f cd 09 cc 90 0f 0b 90 e9 1d fc ff ff 90 0f 0b 90 e9 86 fc ff ff 90 <0f> 0b 90 eb d4 89 d9 80 e1 07 80 c1 03 38 c1 0f 8c 49 fb ff ff 48
RSP: 0000:ffffc9000441f850 EFLAGS: 00010046
RAX: 1ffff11004b43000 RBX: ffffffff8dba7b10 RCX: ffffffff8192ec5f
RDX: 0000000000000000 RSI: 0000000000000008 RDI: ffff888025a18000
RBP: ffff888025a182a8 R08: ffff888025a18007 R09: 1ffff11004b43000
R10: dffffc0000000000 R11: ffffed1004b43001 R12: dffffc0000000000
R13: ffff888025a18000 R14: ffff8880b863ab00 R15: ffff888025a18000
FS:  00007f43893816c0(0000) GS:ffff888125d2a000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007ffc4765f9f8 CR3: 0000000031872000 CR4: 00000000003526f0
Call Trace:
 <TASK>
 class_sched_change_destructor kernel/sched/sched.h:3956 [inline]
 rt_mutex_setprio+0x488/0xb70 kernel/sched/core.c:7331
 rt_mutex_adjust_prio kernel/locking/rtmutex.c:539 [inline]
 remove_waiter+0x7f5/0xaf0 kernel/locking/rtmutex.c:1567
 rt_mutex_cleanup_proxy_lock+0x6c/0x100 kernel/locking/rtmutex_api.c:458
 futex_lock_pi+0x530/0xa90 kernel/futex/pi.c:1067
 do_futex+0x292/0x420 kernel/futex/syscalls.c:146
 __do_sys_futex kernel/futex/syscalls.c:207 [inline]
 __se_sys_futex+0x36f/0x400 kernel/futex/syscalls.c:188
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xfa/0xf80 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f438858f749
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:00007f4389381038 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca
RAX: ffffffffffffffda RBX: 00007f43887e5fa0 RCX: 00007f438858f749
RDX: 0000000000000002 RSI: 0000000000000086 RDI: 000020000000cffc
RBP: 00007f4388613f91 R08: 0000000000000000 R09: 00000000fffffffc
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f43887e6038 R14: 00007f43887e5fa0 R15: 00007ffc0d485f98
 </TASK>


---
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