[Bug 82081] New: Massive slowdowns and "Kicking stuck wait on blitter ring" on 4k DP1.2 monitor

[bugzilla-daemon at freedesktop.org]

https://bugs.freedesktop.org/show_bug.cgi?id=82081

          Priority: medium
            Bug ID: 82081
                CC: intel-gfx-bugs at lists.freedesktop.org
          Assignee: intel-gfx-bugs at lists.freedesktop.org
           Summary: Massive slowdowns and "Kicking stuck wait on blitter
                    ring" on 4k DP1.2 monitor
        QA Contact: intel-gfx-bugs at lists.freedesktop.org
          Severity: normal
    Classification: Unclassified
                OS: Linux (All)
          Reporter: palmer at dabbelt.com
          Hardware: x86-64 (AMD64)
            Status: NEW
           Version: XOrg CVS
         Component: DRM/Intel
           Product: DRI

Created attachment 103893
  --> https://bugs.freedesktop.org/attachment.cgi?id=103893&action=edit
/sys/class/drm/card0/error

When I try to run any OpenGL application (specifically glxgears in this case)
when my 4k DP1.2 monitor is plugged in my X slows down to a crawl and the
application performs very poorly (glxgears reports between 0.1 and 0.5 FPS). 
Note that this does not happen on my eDP non-4K monitor, so I can only assume
it's somehow related to DP1.2/MST.  I can ^C glxgears, which takes maybe 10
seconds or so to stop.  The system then appears to re-fire a udev hotplug rule
for my monitor, but is otherwise perfectly fine after glxgears quits.

I'm running 3.15.8 from the linux-stable git on an up-to-date Gentoo system.

I know absolutely nothing about DRM, so I'm afraid all I can really do is try
and follow what my "dmesg" says.  Here's a log from three runs: first a
glxgears run around 45s after boot with my DP1.2 monitor plugged in, then a run
with the internal LCD (which may have produced that message at 389), and then a
second run with the DP1.2 monitor plugged in around 700s.

I've also attached the suggested crash dump, which is from the third run (the
second run with the DP1.2 monitor, when the system slowed down).

[   45.883781] [drm] GPU HANG: ecode -1:0x00000000, reason: Kicking stuck wait
on blitter ring, action: continue
[   45.883787] [drm] GPU hangs can indicate a bug anywhere in the entire gfx
stack, including userspace.
[   45.883789] [drm] Please file a _new_ bug report on bugs.freedesktop.org
against DRI -> DRM/Intel
[   45.883790] [drm] drm/i915 developers can then reassign to the right
component if it's not a kernel issue.
[   45.883792] [drm] The gpu crash dump is required to analyze gpu hangs, so
please always attach it.
[   45.883794] [drm] GPU crash dump saved to /sys/class/drm/card0/error
[   49.942317] [drm] GPU HANG: ecode -1:0x00000000, reason: Kicking stuck wait
on blitter ring, action: continue
[   54.090836] [drm] GPU HANG: ecode -1:0x00000000, reason: Kicking stuck wait
on blitter ring, action: continue
[   60.058668] [drm] GPU HANG: ecode -1:0x00000000, reason: Kicking stuck wait
on blitter ring, action: continue
[   64.087182] [drm] GPU HANG: ecode -1:0x00000000, reason: Kicking stuck wait
on blitter ring, action: continue
[  389.473669] [drm:ivb_err_int_handler] *ERROR* Pipe B FIFO underrun
[  585.887658] kworker/u16:0 (6) used greatest stack depth: 11224 bytes left
[  702.796036] [drm] GPU HANG: ecode -1:0x00000000, reason: Kicking stuck wait
on blitter ring, action: continue
[  706.854572] [drm] GPU HANG: ecode -1:0x00000000, reason: Kicking stuck wait
on blitter ring, action: continue

Here is some other stuff that may be relevant?

palmer palmer-mbp2014 ~ $ uname -a
Linux palmer-mbp2014 3.15.8 #9 SMP Sat Aug 2 18:46:42 PDT 2014 x86_64 Intel(R)
Core(TM) i7-4750HQ CPU @ 2.00GHz GenuineIntel GNU/Linux

palmer-mbp2014 palmer # emerge -vp xorg-x11 mesa

These are the packages that would be merged, in order:

Calculating dependencies... done!
[ebuild   R    ] x11-base/xorg-x11-7.4-r2  0 kB
[ebuild   R    ] media-libs/mesa-10.0.4  USE="classic egl gallium nptl -bindist
-debug -gbm -gles1 -gles2 -llvm -llvm-shared-libs -opencl -openvg -osmesa
-pax_kernel -pic -r600-llvm-compiler (-selinux) -vdpau -wayland -xa -xvmc"
ABI_X86="(64) (-32) (-x32)" VIDEO_CARDS="intel (-freedreno) -i915 -i965 -ilo
-nouveau -r100 -r200 -r300 -r600 -radeon -radeonsi -vmware" 6,636 kB

-- 
You are receiving this mail because:
You are the QA Contact for the bug.
You are on the CC list for the bug.
You are the assignee for the bug.
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.freedesktop.org/archives/intel-gfx-bugs/attachments/20140803/bbe7147e/attachment-0001.html>