Fixing R300 hangs

[Mike A. Harris]

David Nielsen wrote:
> søn, 26 02 2006 kl. 14:14 -0500, skrev John Thacker:
> 
>>Mike A. Harris wrote:
>>
>>
>>>Doing a bit of investigation has shown that it isn't just the
>>>r300 DRI driver that is instable, but even just loading the X server
>>>DRI module with many r300 or newer cards causes the system to crash,
>>>even if DRI is actually disabled, and even if the r300 DRI driver is
>>>not even present on the system.
>>
>>I believe that this is almost surely this problem:
>>http://lists.freedesktop.org/archives/xorg/2005-December/011678.html
>>https://bugs.freedesktop.org/show_bug.cgi?id=4847
>>http://webcvs.freedesktop.org/xorg/driver/xf86-video-ati/ChangeLog?rev=1.22&view=markup
>>
>>There are some important memory map and other fixes for Radeon cards
>>(especially R300 and above) that hit the xorg CVS tree on February
>>17, after 7.0.  (The author considered them a little too experimental
>>for 7.0.)  Apparently without the fixes many people saw lockups using 
>>R300 cards without DRI enabled or the r300 DRI drive present.  However,
>>with these fixes the instability goes away.
>>
>>Perhaps these upstream CVS patches could be integrated into the Fedora
>>Core patches.  If so, the r300 driver could be left in FC5.  Of course,
>>we are running low on time, but I think it's a relatively critical bug.
>>Especially if the recent Mesa change doesn't solve the crashes for
>>everyone.
> 
> Mike, could we get a set of testing rpms akin to what you did with the
> fonts package to see if this fixes the r300 behavioral problems?

Sure, check the Xorg sources/spec out of Fedora CVS, snag the patches
from upstream CVS with cvs rdiff, apply them to the package, appending
a custom identifier to the Release field such as:  .dnielsen.1 to
distinguish it from official Red Hat packaging, build new rpms and
upload them to a custom yum repository.  Might want to call it something
like "David's Experimental X.org" or something to distinguish it.

That would provide a useful resource for the various people who would
like to volunteer to help test and stabilize the r300 DRI support.  It
would also be a good idea to join the #dri-devel and #xorg-devel IRC
channels on freenode, where most of the core developers frequent.  That
can be useful for realtime debugging discussion, etc.  Another channel
is #fedora-x, which I've been using for Fedora specific development/
packaging/maintenance discussion, but the other 2 channels are more
useful for general issues.

Once you've got rpms ready, my recommendation would be to post an email
to announce them to fedora-devel-list, fedora-test-list, and the main
X.Org mailing list - xorg at lists.freedesktop.org

It's good to see more and more people volunteering to help out the
X.Org project like this!  It sure confirms the X.Org bazaar style
development model was the right direction, over the closed development
model of the previous X Window System implementation that was commonly
shipped in the past.




-- 
Mike A. Harris  *  Open Source Advocate  *  http://mharris.ca
                       Proud Canadian.