------------[ cut here ]------------
WARNING: drivers/gpu/drm/drm_vblank.c:1318 at drm_wait_one_vblank+0x198/0x274 drivers/gpu/drm/drm_vblank.c:1318, CPU#1: kworker/1:4/3047
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: 3047 Comm: kworker/1:4 Not tainted syzkaller #0 PREEMPT 
Hardware name: ARM-Versatile Express
Workqueue: events drm_fb_helper_damage_work
Call trace: 
[<80201a40>] (dump_backtrace) from [<80201b34>] (show_stack+0x18/0x1c arch/arm/kernel/traps.c:257)
 r7:82290da0 r6:00000000 r5:822a2700 r4:00000001
[<80201b1c>] (show_stack) from [<8021ed9c>] (__dump_stack lib/dump_stack.c:94 [inline])
[<80201b1c>] (show_stack) from [<8021ed9c>] (dump_stack_lvl+0x5c/0x70 lib/dump_stack.c:120)
[<8021ed40>] (dump_stack_lvl) from [<8021edc8>] (dump_stack+0x18/0x1c lib/dump_stack.c:129)
 r7:82290da0 r6:843f2400 r5:00000000 r4:82a7cd14
[<8021edb0>] (dump_stack) from [<802025c4>] (vpanic+0xe0/0x2e4 kernel/panic.c:490)
[<802024e4>] (vpanic) from [<802027fc>] (trace_suspend_resume+0x0/0xd8 kernel/panic.c:627)
 r7:80b13a10
[<802027c8>] (panic) from [<80251f68>] (check_panic_on_warn kernel/panic.c:377 [inline])
[<802027c8>] (panic) from [<80251f68>] (get_taint+0x0/0x1c kernel/panic.c:372)
 r3:8280c504 r2:00000001 r1:8228958c r0:82290da0
[<80251ef0>] (check_panic_on_warn) from [<802520e0>] (__warn+0x94/0x1a0 kernel/panic.c:902)
[<8025204c>] (__warn) from [<802523d4>] (warn_slowpath_fmt+0x1e8/0x1f4 kernel/panic.c:937)
 r8:00000009 r7:8231d034 r6:eba65dd4 r5:843f2400 r4:00000000
[<802521f0>] (warn_slowpath_fmt) from [<80b13a10>] (drm_wait_one_vblank+0x198/0x274 drivers/gpu/drm/drm_vblank.c:1318)
 r10:83018605 r9:83ffdc44 r8:00000000 r7:0000913e r6:00000000 r5:00000000
 r4:8395c400
[<80b13878>] (drm_wait_one_vblank) from [<80b13b04>] (drm_crtc_wait_one_vblank+0x18/0x1c drivers/gpu/drm/drm_vblank.c:1334)
 r9:8395c400 r8:83ffee00 r7:eba65ea4 r6:8395c400 r5:00000000 r4:83878040
[<80b13aec>] (drm_crtc_wait_one_vblank) from [<80b17614>] (drm_client_modeset_wait_for_vblank+0x60/0x74 drivers/gpu/drm/drm_client_modeset.c:1330)
[<80b175b4>] (drm_client_modeset_wait_for_vblank) from [<80b30a94>] (drm_fb_helper_fb_dirty drivers/gpu/drm/drm_fb_helper.c:334 [inline])
[<80b175b4>] (drm_client_modeset_wait_for_vblank) from [<80b30a94>] (drm_fb_helper_damage_work+0x80/0x1e0 drivers/gpu/drm/drm_fb_helper.c:372)
 r7:eba65ea4 r6:83ffeeb8 r5:00000000 r4:83ffee98
[<80b30a14>] (drm_fb_helper_damage_work) from [<80276cec>] (process_one_work+0x1b8/0x4f8 kernel/workqueue.c:3257)
 r9:83016170 r8:843f2400 r7:ddde3b40 r6:83018600 r5:83ffee98 r4:85a59800
[<80276b34>] (process_one_work) from [<8027796c>] (process_scheduled_works kernel/workqueue.c:3340 [inline])
[<80276b34>] (process_one_work) from [<8027796c>] (worker_thread+0x1c4/0x394 kernel/workqueue.c:3421)
 r10:61c88647 r9:843f2400 r8:82804d80 r7:85a5982c r6:ddde3b40 r5:ddde3b60
 r4:85a59800
[<802777a8>] (worker_thread) from [<8027facc>] (kthread+0x128/0x27c kernel/kthread.c:463)
 r10:00000000 r9:85a59800 r8:802777a8 r7:df879e68 r6:85a41b00 r5:843f2400
 r4:00000001
[<8027f9a4>] (kthread) from [<80200114>] (ret_from_fork+0x14/0x20 arch/arm/kernel/entry-common.S:137)
Exception stack(0xeba65fb0 to 0xeba65ff8)
5fa0:                                     00000000 00000000 00000000 00000000
5fc0: 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000
5fe0: 00000000 00000000 00000000 00000000 00000013 00000000
 r10:00000000 r9:00000000 r8:00000000 r7:00000000 r6:00000000 r5:8027f9a4
 r4:85a45480
SMP: failed to stop secondary CPUs
Rebooting in 86400 seconds..