------------[ cut here ]------------
WARNING: drivers/gpu/drm/drm_vblank.c:1329 at drm_crtc_wait_one_vblank+0x19c/0x21c drivers/gpu/drm/drm_vblank.c:1329, CPU#1: kworker/1:0/23
faux_driver vkms: [drm] vblank wait timed out on crtc 0
Modules linked in:
Kernel panic - not syncing: kernel: panic_on_warn set ...
CPU: 1 UID: 0 PID: 23 Comm: kworker/1:0 Not tainted syzkaller #0 PREEMPT 
Hardware name: ARM-Versatile Express
Workqueue: events drm_fb_helper_damage_work
Call trace: 
[<80201998>] (dump_backtrace) from [<80201a8c>] (show_stack+0x18/0x1c arch/arm/kernel/traps.c:257)
 r7:82a20f78 r6:00000000 r5:82332bbc r4:00000001
[<80201a74>] (show_stack) from [<8021e580>] (__dump_stack lib/dump_stack.c:94 [inline])
[<80201a74>] (show_stack) from [<8021e580>] (dump_stack_lvl+0x5c/0x70 lib/dump_stack.c:120)
[<8021e524>] (dump_stack_lvl) from [<8021e5ac>] (dump_stack+0x18/0x1c lib/dump_stack.c:129)
 r7:82a20f78 r6:00000000 r5:8317a4c0 r4:82c83d40
[<8021e594>] (dump_stack) from [<80202590>] (vpanic+0x114/0x320 kernel/panic.c:651)
[<8020247c>] (vpanic) from [<802027d0>] (trace_suspend_resume+0x0/0x100 kernel/panic.c:788)
 r7:80b728e4
[<8020279c>] (panic) from [<80250a80>] (check_panic_on_warn kernel/panic.c:525 [inline])
[<8020279c>] (panic) from [<80250a80>] (get_taint+0x0/0x1c kernel/panic.c:520)
 r3:82a0b144 r2:00000001 r1:82318920 r0:8232027c
[<80250a08>] (check_panic_on_warn) from [<80250bfc>] (__warn+0x98/0x1a4 kernel/panic.c:1104)
[<80250b64>] (__warn) from [<80250ef0>] (warn_slowpath_fmt+0x1e8/0x1f4 kernel/panic.c:1144)
 r8:00000009 r7:823b0a4c r6:df879dbc r5:8317a4c0 r4:00000000
[<80250d0c>] (warn_slowpath_fmt) from [<80b728e4>] (drm_crtc_wait_one_vblank+0x19c/0x21c drivers/gpu/drm/drm_vblank.c:1329)
 r10:84328844 r9:ffffff92 r8:00000000 r7:00001f6b r6:00000000 r5:00000000
 r4:833a8000
[<80b72748>] (drm_crtc_wait_one_vblank) from [<80b764a0>] (drm_client_modeset_wait_for_vblank+0x60/0x74 drivers/gpu/drm/drm_client_modeset.c:1331)
 r10:833a7c50 r9:833a80c4 r8:833a8188 r7:00000000 r6:833a8000 r5:00000000
 r4:83f89040
[<80b76440>] (drm_client_modeset_wait_for_vblank) from [<80b918d0>] (drm_fb_helper_fb_dirty drivers/gpu/drm/drm_fb_helper.c:327 [inline])
[<80b76440>] (drm_client_modeset_wait_for_vblank) from [<80b918d0>] (drm_fb_helper_damage_work+0x190/0x3d4 drivers/gpu/drm/drm_fb_helper.c:365)
 r7:00000000 r6:838874b4 r5:83887494 r4:83887400
[<80b91740>] (drm_fb_helper_damage_work) from [<802761e8>] (process_one_work+0x1c8/0x580 kernel/workqueue.c:3322)
 r10:8302ae05 r9:8317a4c0 r8:01800000 r7:ddde4f00 r6:8302ae00 r5:83887494
 r4:83112580
[<80276020>] (process_one_work) from [<80276e94>] (process_scheduled_works kernel/workqueue.c:3405 [inline])
[<80276020>] (process_one_work) from [<80276e94>] (worker_thread+0x16c/0x318 kernel/workqueue.c:3486)
 r10:ddde4f00 r9:831125b0 r8:8317a4c0 r7:82a03d80 r6:ddde4f20 r5:ddde4f00
 r4:83112580
[<80276d28>] (worker_thread) from [<80281710>] (kthread+0x11c/0x154 kernel/kthread.c:436)
 r10:00000000 r9:df819d10 r8:83112500 r7:83112580 r6:80276d28 r5:8317a4c0
 r4:8310a800
[<802815f4>] (kthread) from [<80200114>] (ret_from_fork+0x14/0x20 arch/arm/kernel/entry-common.S:137)
Exception stack(0xdf879fb0 to 0xdf879ff8)
9fa0:                                     00000000 00000000 00000000 00000000
9fc0: 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000
9fe0: 00000000 00000000 00000000 00000000 00000013 00000000
 r9:00000000 r8:00000000 r7:00000000 r6:00000000 r5:802815f4 r4:8310a800
SMP: failed to stop secondary CPUs
Rebooting in 86400 seconds..