[syzbot] [kernel?] WARNING: locking bug in sched_mm_cid_exit_signals

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit:    7503345ac5f5 Merge tag 'block-6.13-20241207' of git://git...
git tree:       upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=124e4820580000
kernel config:  https://syzkaller.appspot.com/x/.config?x=1362a5aee630ff34
dashboard link: https://syzkaller.appspot.com/bug?extid=a7dddc711489766b3d23
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/f66ad6e028a7/disk-7503345a.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/822436e7e431/vmlinux-7503345a.xz
kernel image: https://storage.googleapis.com/syzbot-assets/264599a99f7f/bzImage-7503345a.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+a7dddc711489766b3d23@xxxxxxxxxxxxxxxxxxxxxxxxx

------------[ cut here ]------------
DEBUG_LOCKS_WARN_ON(1)
WARNING: CPU: 0 PID: 7950 at kernel/locking/lockdep.c:232 hlock_class kernel/locking/lockdep.c:232 [inline]
WARNING: CPU: 0 PID: 7950 at kernel/locking/lockdep.c:232 check_wait_context kernel/locking/lockdep.c:4850 [inline]
WARNING: CPU: 0 PID: 7950 at kernel/locking/lockdep.c:232 __lock_acquire+0x564/0x2100 kernel/locking/lockdep.c:5176
Modules linked in:
CPU: 0 UID: 0 PID: 7950 Comm: syz.4.614 Not tainted 6.13.0-rc1-syzkaller-00337-g7503345ac5f5 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024
RIP: 0010:hlock_class kernel/locking/lockdep.c:232 [inline]
RIP: 0010:check_wait_context kernel/locking/lockdep.c:4850 [inline]
RIP: 0010:__lock_acquire+0x564/0x2100 kernel/locking/lockdep.c:5176
Code: 00 00 83 3d 91 c8 9e 0e 00 75 23 90 48 c7 c7 20 95 0a 8c 48 c7 c6 20 98 0a 8c e8 17 62 e5 ff 48 ba 00 00 00 00 00 fc ff df 90 <0f> 0b 90 90 90 31 db 48 81 c3 c4 00 00 00 48 89 d8 48 c1 e8 03 0f
RSP: 0018:ffffc90005877670 EFLAGS: 00010046
RAX: 55799a8e77b73a00 RBX: 00000000000016d8 RCX: ffff88802d680000
RDX: dffffc0000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 00000000000c16d8 R08: ffffffff81601c02 R09: 1ffff110170c519a
R10: dffffc0000000000 R11: ffffed10170c519b R12: ffff88802d680ac4
R13: 0000000000000005 R14: 1ffff11005ad0165 R15: ffff88802d680b28
FS:  00007fa9992c46c0(0000) GS:ffff8880b8600000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000000110c337a3a CR3: 000000005ebca000 CR4: 0000000000350ef0
Call Trace:
 <TASK>
 lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5849
 _raw_spin_lock_nested+0x31/0x40 kernel/locking/spinlock.c:378
 raw_spin_rq_lock_nested+0xb0/0x140 kernel/sched/core.c:606
 raw_spin_rq_lock kernel/sched/sched.h:1514 [inline]
 _raw_spin_rq_lock_irqsave kernel/sched/sched.h:1534 [inline]
 rq_lock_irqsave kernel/sched/sched.h:1799 [inline]
 class_rq_lock_irqsave_constructor kernel/sched/sched.h:1848 [inline]
 sched_mm_cid_exit_signals+0x17b/0x4b0 kernel/sched/core.c:10606
 exit_signals+0x357/0x5c0 kernel/signal.c:3111
 do_exit+0x6b4/0x28e0 kernel/exit.c:895
 do_group_exit+0x207/0x2c0 kernel/exit.c:1087
 get_signal+0x16b2/0x1750 kernel/signal.c:3017
 arch_do_signal_or_restart+0x96/0x860 arch/x86/kernel/signal.c:337
 exit_to_user_mode_loop kernel/entry/common.c:111 [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+0xce/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: 0033:0x7fa99857fed9
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:00007fa9992c40e8 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca
RAX: fffffffffffffe00 RBX: 00007fa998746168 RCX: 00007fa99857fed9
RDX: 0000000000000000 RSI: 0000000000000080 RDI: 00007fa998746168
RBP: 00007fa998746160 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00007fa99874616c
R13: 0000000000000000 R14: 00007ffc44f667e0 R15: 00007ffc44f668c8
 </TASK>


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