i915 DRM problems in lucid.

[Robert Hooker]

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.

> 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!

Robert