I got my screen scrumbled, but the system recovered.

[drm] stuck on render ring
[drm] GPU HANG: ecode 3:0:0x2b0fffc7, in Xorg [1281], reason: Ring hung, action: reset
[drm] GPU hangs can indicate a bug anywhere in the entire gfx stack, including userspace.
[drm] Please file a _new_ bug report on bugs.freedesktop.org against DRI -> DRM/Intel
[drm] drm/i915 developers can then reassign to the right component if it's not a kernel issue.
[drm] The gpu crash dump is required to analyze gpu hangs, so please always attach it.
[drm] GPU crash dump saved to /sys/class/drm/card0/error
------------[ cut here ]------------
WARNING: CPU: 0 PID: 3286 at /build/linux-_Kyesa/linux-4.2.0/drivers/gpu/drm/i915/intel_display.c:3296 intel_crtc_wait_for_pending_flips+0x17c/0x220 [i915]()
WARN_ON(ret)
Modules linked in: rfcomm pci_stub vboxpci(OE) vboxnetadp(OE) vboxnetflt(OE) vboxdrv(OE) md4 nls_utf8 cifs fscache bnep binfmt_misc btusb btrtl btbcm btintel bluetooth arc4 snd_hda_codec_idt snd_hda_codec_generic snd_hda_intel snd_hda_codec snd_hda_core snd_hwdep applesmc input_polldev snd_pcm snd_seq_midi snd_seq_midi_event coretemp kvm_intel input_leds snd_rawmidi ath5k ath kvm snd_seq mac80211 snd_seq_device snd_timer lpc_ich snd cfg80211 soundcore shpchp mac_hid f2fs parport_pc ppdev sunrpc lp parport autofs4 hid_appleir hid_generic usbhid hid firewire_ohci i915 pata_acpi i2c_algo_bit firewire_core drm_kms_helper crc_itu_t drm video sky2
CPU: 0 PID: 3286 Comm: kworker/u4:2 Tainted: G           OE   4.2.0-35-generic #40-Ubuntu
Hardware name: Apple Inc. Macmini2,1/Mac-F4208EAA, BIOS     MM21.88Z.009A.B00.0706281359 06/28/07
Workqueue: i915-hangcheck i915_hangcheck_elapsed [i915]
 c1a6c9a7 63a689c4 00000286 f1141d48 c1765c3c f1141d88 f8b5eab0 f1141d78
 c106bd17 f8b6c99d f1141da8 00000cd6 f8b5eab0 00000ce0 f8b00b7c f8b00b7c
 f5df8000 f5cca434 00000001 f1141d94 c106bd8e 00000009 f1141d88 f8b6c99d
Call Trace:
 [<c1765c3c>] dump_stack+0x58/0x72
 [<c106bd17>] warn_slowpath_common+0x87/0xc0
 [<f8b00b7c>] ? intel_crtc_wait_for_pending_flips+0x17c/0x220 [i915]
 [<f8b00b7c>] ? intel_crtc_wait_for_pending_flips+0x17c/0x220 [i915]
 [<c106bd8e>] warn_slowpath_fmt+0x3e/0x60
 [<f8b00b7c>] intel_crtc_wait_for_pending_flips+0x17c/0x220 [i915]
 [<f89200d4>] ? drm_modeset_lock_all_crtcs+0x84/0x90 [drm]
 [<f8b01f44>] intel_crtc_disable_planes+0x34/0xf0 [i915]
 [<f8b020aa>] intel_prepare_reset+0x6a/0x80 [i915]
 [<f8ad3c47>] i915_handle_error+0x147/0x6e0 [i915]
 [<c10c18a1>] ? vprintk_default+0x41/0x60
 [<f8ad4463>] i915_hangcheck_elapsed+0x233/0x410 [i915]
 [<c1082a0a>] process_one_work+0x12a/0x420
 [<c1082d37>] worker_thread+0x37/0x490
 [<c1082d00>] ? process_one_work+0x420/0x420
 [<c10883f6>] kthread+0xa6/0xc0
 [<c176b941>] ret_from_kernel_thread+0x21/0x30
 [<c1088350>] ? kthread_create_on_node+0x170/0x170
---[ end trace 22540e0f3845346a ]---
drm/i915: Resetting chip after gpu hang



This was on Kubuntu 15.10 with kernel 4.2.0-35-generic