[Intel-gfx] 2.6.38-rc8 regressions

[Jan Niehusmann]

Hello,

just to provide some testing feedback. I didn't have time (and probably
not even the necessary skills) to further diagnose these issues. But
as I don't remember seeing these problems with 2.6.37, maybe the
observations are interesting to you:

With 2.6.38-rc8 I see the following graphics related regressions
(relative to 2.6.37) on a Thinkpad X61s with "Intel Corporation Mobile
GM965/GL960 Integrated Graphics Controller" (PCI ID 8086:2a02).
Userspace is debian/squeeze.

1) Every now and then, terminal windows (urxvt) do not properly update
their contents. After issueing a command like 'ls', which writes
several lines of text at once, some lines are completely missing. It's
not garbled glyphs, but full lines of text completely missing.

Interestingly, sometimes the correct contents of the full window become visible
for a split second. So they seem to be 'somewhere' accessible to the GPU, just
not shown on the screen.

When a single character in an affected line gets updated (e.g. by marking
it with the cursor - or even by an update in a different console window
next to the one affected) the correct contents of the full line become
and stay visible.

When this problem occurs, it does so reproducibly: About every third
command writing to the terminal shows the behaviour. In that situation,
just closing and reopening the lid solves the problem: Console windows
work as expected again, and AFAICT the problem doesn't reoccur until the
next reboot or suspend/resume cycle.

2) I just had a full hang of the GPU (black screen) after opening a web
page containing a video. kernel.log contains the following messages:

Mar 14 09:09:37 x61s kernel: [drm:i915_hangcheck_elapsed] *ERROR* Hangcheck timer elapsed... GPU hung
Mar 14 09:09:37 x61s kernel: [drm:i915_do_wait_request] *ERROR* i915_do_wait_request returns -11 (awaiting 10172 at 10171, next 10173)
Mar 14 09:09:37 x61s kernel: [drm:init_ring_common] *ERROR* render ring initialization failed ctl 00000000 head 00000000 tail 00000000 start 00000000
Mar 14 09:09:44 x61s kernel: [drm:i915_hangcheck_elapsed] *ERROR* Hangcheck timer elapsed... GPU hung
Mar 14 09:09:44 x61s kernel: [drm:init_ring_common] *ERROR* render ring initialization failed ctl 00000000 head 00000000 tail 00000000 start 00000000
Mar 14 09:09:44 x61s kernel: [drm:i915_do_wait_request] *ERROR* something (likely vbetool) disabled interrupts, re-enabling
Mar 14 09:09:44 x61s kernel: [drm:i915_do_wait_request] *ERROR* something (likely vbetool) disabled interrupts, re-enabling
Mar 14 09:09:44 x61s kernel: [drm:i915_do_wait_request] *ERROR* something (likely vbetool) disabled interrupts, re-enabling
Mar 14 09:09:44 x61s kernel: [drm:i915_do_wait_request] *ERROR* something (likely vbetool) disabled interrupts, re-enabling
Mar 14 09:09:44 x61s kernel: [drm:i915_do_wait_request] *ERROR* something (likely vbetool) disabled interrupts, re-enabling
[...]
Mar 14 09:09:45 x61s kernel: [drm:i915_do_wait_request] *ERROR* something (likely vbetool) disabled interrupts, re-enabling
Mar 14 09:09:45 x61s kernel: [drm:i915_do_wait_request] *ERROR* something (likely vbetool) disabled interrupts, re-enabling
Mar 14 09:09:45 x61s kernel: [drm:i915_hangcheck_elapsed] *ERROR* Hangcheck timer elapsed... GPU hung
Mar 14 09:09:45 x61s kernel: [drm:i915_do_wait_request] *ERROR* i915_do_wait_request returns -11 (awaiting 10180 at 10171, next 10181)
Mar 14 09:09:45 x61s kernel: [drm:i915_reset] *ERROR* GPU hanging too fast, declaring wedged!
Mar 14 09:09:45 x61s kernel: [drm:i915_reset] *ERROR* Failed to reset chip.

The same (probably) happened ten days ago with 2.6.38-rc6:

Mar  4 10:06:22 x61s kernel: [drm:i915_hangcheck_elapsed] *ERROR* Hangcheck timer elapsed... GPU hung
Mar  4 10:06:22 x61s kernel: [drm:i915_do_wait_request] *ERROR* i915_do_wait_request returns -11 (awaiting 50785 at 50784, next 50786)
Mar  4 10:06:22 x61s kernel: [drm:init_ring_common] *ERROR* render ring initialization failed ctl 00000000 head 00000000 tail 00000000 start 00000000
Mar  4 10:06:28 x61s kernel: [drm:i915_hangcheck_elapsed] *ERROR* Hangcheck timer elapsed... GPU hung
Mar  4 10:06:28 x61s kernel: [drm:init_ring_common] *ERROR* render ring initialization failed ctl 00000000 head 00000000 tail 00000000 start 00000000
Mar  4 10:06:31 x61s kernel: [drm:i915_hangcheck_elapsed] *ERROR* Hangcheck timer elapsed... GPU hung
Mar  4 10:06:31 x61s kernel: [drm:i915_reset] *ERROR* GPU hanging too fast, declaring wedged!
Mar  4 10:06:31 x61s kernel: [drm:i915_reset] *ERROR* Failed to reset chip.

So it doesn't happen particularly often, but still too often to just ignore it.

Regards,
Jan