Bug#661696: drm/i915: wrong fifo size due to uncareful refactoring which results in an xserver crash at 800x600

[Lukas Anzinger <l.anzinger@gmail.com>]

Hi Jonathan,

looks good to me.

I've also reported this bug upstream under #42839.

Regards,

Lukas

On Wed, Feb 29, 2012 at 19:36, Jonathan Nieder <jrnieder@gmail.com> wrote:
> tags 661696 = upstream patch moreinfo
> quit
>
> Hi Lukas,
>
> Lukas Anzinger wrote:
>
>> During a refactoring of the i915 driver a regression has been introduced
>> ([...]h=e70236a8d3d0a4c100a0b9f7d394d9bda9c56aca): For some chipsets
>> the wrong fifo size is determined which results in lot's of pixel
>> errors when starting the xserver and choosing 800x600 as a
>> resolution. If another resolution is used (eg. 1024x768 or
>> 1280x1024), I don't encounter this problem.
>>
>> I've attached a patch that fixes the problem (no pixel errors
>> anymore) and determines the correct fifo size.
>
> Thanks for the report and analysis.  Please test the attached patch
> against 2.6.32.y or a squeeze kernel.  If it works, we can send this
> to Greg for inclusion in the 2.6.32.y series so everyone benefits.
>
> Hope that helps,
> Jonathan