[syzbot] [dri?] WARNING in __drm_atomic_helper_set_config

[syzbot <syzbot+ca23c8570669ead78867@syzkaller.appspotmail.com>]

Hello,

syzbot found the following issue on:

HEAD commit:    4235cb24ec1e Merge tag 'vfs-7.2-rc5.fixes' of git://git.ke..
git tree:       upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=1753a7b1580000
kernel config:  https://syzkaller.appspot.com/x/.config?x=f221a1b5d497ed15
dashboard link: https://syzkaller.appspot.com/bug?extid=ca23c8570669ead78867
compiler:       gcc (Debian 14.2.0-19) 14.2.0, GNU ld (GNU Binutils for Debian) 2.44
userspace arch: i386

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

Downloadable assets:
disk image (non-bootable): https://storage.googleapis.com/syzbot-assets/d900f083ada3/non_bootable_disk-4235cb24.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/68eef4847f46/vmlinux-4235cb24.xz
kernel image: https://storage.googleapis.com/syzbot-assets/77e73df69f7f/bzImage-4235cb24.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+ca23c8570669ead78867@syzkaller.appspotmail.com

------------[ cut here ]------------
!set->fb
WARNING: drivers/gpu/drm/drm_atomic.c:1951 at __drm_atomic_helper_set_config+0xa45/0xee0 drivers/gpu/drm/drm_atomic.c:1951, CPU#0: syz.2.1107/9271
Modules linked in:
CPU: 0 UID: 0 PID: 9271 Comm: syz.2.1107 Tainted: G             L      syzkaller #0 PREEMPT(full) 
Tainted: [L]=SOFTLOCKUP
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2 04/01/2014
RIP: 0010:__drm_atomic_helper_set_config+0xa45/0xee0 drivers/gpu/drm/drm_atomic.c:1951
Code: 84 c0 74 09 3c 03 7f 05 e8 c8 b6 bd fc 45 89 75 38 e9 0e fb ff ff e8 fa 28 4e fc 90 0f 0b 90 e9 9f f7 ff ff e8 ec 28 4e fc 90 <0f> 0b 90 e9 47 f7 ff ff 8b 6c 24 28 e8 da 28 4e fc 49 8d 7c 24 08
RSP: 0018:ffffc9000efb7950 EFLAGS: 00010293
RAX: 0000000000000000 RBX: ffff888029878500 RCX: ffffffff85bb7a4b
RDX: ffff88802a308000 RSI: ffffffff85bb8374 RDI: ffff88802a308000
RBP: ffff88802a874b00 R08: 0000000000000007 R09: fffffffffffff000
R10: ffff888028f94c00 R11: 0000000000000000 R12: ffff888077d2d300
R13: ffff888028f94c00 R14: ffff8880141c1400 R15: ffff88806c029368
FS:  0000000000000000(0000) GS:ffff888096be3000(0063) knlGS:00000000571f8480
CS:  0010 DS: 002b ES: 002b CR0: 0000000080050033
CR2: 0000000000000000 CR3: 0000000027e6e000 CR4: 0000000000352ef0
Call Trace:
 <TASK>
 drm_client_modeset_commit_atomic+0x53d/0x7e0 drivers/gpu/drm/drm_client_modeset.c:1085
 drm_client_modeset_commit_locked+0x14d/0x580 drivers/gpu/drm/drm_client_modeset.c:1207
 drm_client_modeset_commit+0x4f/0x80 drivers/gpu/drm/drm_client_modeset.c:1233
 __drm_fb_helper_restore_fbdev_mode_unlocked.part.0+0x137/0x160 drivers/gpu/drm/drm_fb_helper.c:138
 __drm_fb_helper_restore_fbdev_mode_unlocked drivers/gpu/drm/drm_fb_helper.c:126 [inline]
 drm_fb_helper_restore_fbdev_mode_unlocked+0x93/0xc0 drivers/gpu/drm/drm_fb_helper.c:169
 drm_fbdev_client_restore+0x1b/0x30 drivers/gpu/drm/clients/drm_fbdev_client.c:45
 drm_client_dev_restore+0x205/0x2a0 drivers/gpu/drm/drm_client_event.c:118
 drm_lastclose drivers/gpu/drm/drm_file.c:408 [inline]
 drm_release+0x2c6/0x360 drivers/gpu/drm/drm_file.c:441
 __fput+0x3ff/0xb50 fs/file_table.c:512
 task_work_run+0x150/0x240 kernel/task_work.c:233
 resume_user_mode_work include/linux/resume_user_mode.h:50 [inline]
 __exit_to_user_mode_loop kernel/entry/common.c:70 [inline]
 exit_to_user_mode_loop+0x1d8/0x6f0 kernel/entry/common.c:101
 __exit_to_user_mode_prepare include/linux/irq-entry-common.h:207 [inline]
 syscall_exit_to_user_mode_prepare include/linux/irq-entry-common.h:230 [inline]
 syscall_exit_to_user_mode include/linux/entry-common.h:318 [inline]
 __do_fast_syscall_32+0x701/0x970 arch/x86/entry/syscall_32.c:310
 do_fast_syscall_32+0x32/0x70 arch/x86/entry/syscall_32.c:332
 entry_SYSENTER_compat_after_hwframe+0x84/0x8e
RIP: 0023:0xf703efec
Code: Unable to access opcode bytes at 0xf703efc2.
RSP: 002b:00000000ffb3591c EFLAGS: 00000202 ORIG_RAX: 00000000000001b4
RAX: 0000000000000000 RBX: 0000000000000003 RCX: 000000000000001e
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000202 R12: 0000000000000000
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000
 </TASK>


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