i915 DRM problems in lucid.

[Chase Douglas]

On Sat, Mar 27, 2010 at 2:48 PM, Robert Hooker <sarvatt at ubuntu.com> wrote:
> On Sat, Mar 27, 2010 at 6:09 PM, Chase Douglas
> <chase.douglas at canonical.com> wrote:
>> Hi Robert,
>>
>> On Sat, Mar 27, 2010 at 12:15 PM, Robert Hooker <sarvatt at ubuntu.com> wrote:
>>> Hello, I've found a lot of bug fixes for i915 that seem needed in the
>>> lucid kernel and I thought I'd list them here for consideration since
>>> I'm not having any luck in IRC.
>>
>> Sorry to hear that. We do try to pay attention to #ubuntu-kernel, but
>> sometimes stuff slips through when we get busy. Of course, email's
>> great for making sure we at least see things :).
>>
>>> * GPU hangs after DPMS events
>>> *Quite* a lot of reports of this bug, the fix was included in
>>> 2.6.32-15 but was dropped during the 2.6.33 DRM merge that happened in
>>> 2.6.32-16. Due to the number of people it affects it seems pretty
>>> urgent to bring this back in. Symptoms include hangs after lid close,
>>> idle screen blanking, and suspend/resume. dmesg and old xorg/gdm logs
>>> will show batchbuffer I/O errors when it crashed, EIR is always
>>> 00000000 and it eventually ends up with an assert like this happening
>>> - X: ../../src/i830_batchbuffer.h:79: intel_batch_emit_dword:
>>> Assertion `pI830->batch_ptr != ((void *)0)' failed.
>>>
>>> Bug: https://launchpad.net/bugs/535640
>>> Fix: http://kernel.ubuntu.com/git?p=ubuntu/ubuntu-lucid.git;a=commit;h=7b56712ff524ee55e38afaee3954d125f56a6070
>>
>> Unfortunately, the patch was merged into -16 with the .33 drm
>> backport. You can find it at:
>>
>> http://kernel.ubuntu.com/git?p=ubuntu/ubuntu-lucid.git;a=commitdiff;h=bd53bbe184ca00326a3c21834f41cca7a7bdb6d4#patch44
>>
>> It's a huge commit diff, but if you search for the function,
>> intel_release_load_detect_pipe, you'll find that the patch still
>> exists. So it seems the fix lies elsewhere...
>>
>
> Unfortunately I do not believe this is the case, look at
> drivers/gpu/drm/i915/intel_display.c in the current ubuntu-lucid
> source tree and you can clearly see this fix is not applied to it.
>
> 3666:   struct drm_device *dev = encoder->dev;
>
> 3775:           drm_helper_disable_unused_functions(dev);
>
> which are the two lines removed by this patch exist.

You're right. I didn't pay close enough attention. It does seem that
the change got reverted in the merge. I'll make sure we take care of
this.

>> In general, if you have specific fixes the best thing to do is follow
>> the instructions on the wiki [1]. When you send a patch it gets queued
>> up at [2]. This list is monitored by the release maintainers to ensure
>> that we haven't missed anything.
>>
>> I hope this helps,
>> Chase
>>
>> [1] https://wiki.ubuntu.com/KernelTeam/KernelBugFixing
>> [2] http://patchwork.ozlabs.org/project/ubuntu-kernel/list/
>>
>
> Thanks, I did it this way because I am swamped with other bug fixing
> work and wanted to at least get the info out there, but I will try to
> adhere to that in the future. Sorry for the inconvenience!

No inconvenience! I figured you were aware anyways, but it doesn't
hurt to repeat for others reading the list :). We'll take fixes any
way we can get 'em.

-- Chase