[ubuntu-x] Ubuntu-x mini-meeting minutes

[Bryce Harrington]

We had a ubuntu-x team meeting today to coordinate tasks across several
topics.  Below is a brief summary of the discussions.


== X stack for LTS point release ==

The repository is up with the renamed X stack, and it is successfully
working as a proof-of-concept for the rename procedure.  Next step is to
update it to the Q stack, but that's blocked on the Q stack landing in Q
(which happens after alpha1).

There is a known issue that downgrading from the renamed stack won't
work, but we're not going to be supporting downgrading so we're not
planning to worry about that.  We do need to ensure it's documented
upfront, so testers know what they're getting into.

No actions at this time.  mlankhorst owns the project in general and
will follow up on work items subsequent to the stack merge in Q.


== Updating -nouveau snapshot ==

A new snapshot of the -nouveau DDX tree will be merged into quantal (and
to LTS backports).  This new DDX has some fermi changes that will break
acceleration for fermi for kernels < 3.4, so it is suitable only quantal
and ppas with explicit dependency on the LTS backport kernel.

mlankhorst took the action of liaising with upstream first, then if all
looks ok will coordinate getting this in for quantal (bryce, chris,
timo, et al can sponsor.)


== Hybrid Graphics ==

mlankhorst has been working with airlied upstream on hybrid but it seems
to still be a fair ways off (not looking likely for formally landing in
Q), so he's going to shift focus back to LTS work, nouveau, etc. for the
time being.  Hardware availability for testing remains an issue, so
near-term tasks involve addressing that need.


== SNA for Intel Graphics ==

SNA is the new 2D acceleration technology for the Intel graphics driver.
It's been under development and testing upstream for quite some time,
but is generally considered "ready for use" by upstream.  Debian has it
enabled in experimental but not unstable at this time.

We enable SNA in our xorg-edgers PPA for preliminary testing.  After a
week if it doesn't seem to have caused severe breakage, we'll go ahead
and enable it, and then re-evaluate it some time prior to alpha-2,
giving consideration to bug reports filed during this period.  Bryce
will handle forwarding bug reports to Intel and working with them
towards fixes.  At the re-evaluation point we will consider the level of
stability and decide whether to return to UXA or move ahead with SNA.


== Mesa 8.0.3 SRU ==

Mesa 8.0.3 is a bug-fix-only release.  We believe this new mesa may
solve a number of hard-to-analyze GPU lockups and corruption problems
that people are seeing, so we feel that 8.0.3 is vital to get out to
the LTS users.

We will be upgrading to it in quantal after alpha-1, and we'd like to
try SRU'ing the full package for precise.  This is as opposed to
cherrypicking specific patches out of it, as we have done historically;
the problem is that many fixes fix legitimate problems but it's quite
hard to match those to user-reported bugs in launchpad.

To help temper regression fears, Bryce will do A/B piglit testing on a
few video drivers to demonstrate lack of regression, Chris will write up
a metabug with a detailed explanation of each change to help, and we'll
seek out a non-X team SRU reviewer for an independent set of eyes.


== Mesa Binary Packages Cleanup ==

Proposed to drop 8-bit and 16-bit osmesa binary packages.  We don't
think anyone actually needs these, and dropping them would speed up our
builds.  We'd still build 23bit libosmesa.

Proposed to drop libgl1-mesa-swx11.  This conflicts with some of the
other mesa binary packages, so if you blindly 'dpkg -i *.deb' on your
freshly built mesa packages, breakage ensues.  Dropping this fixes that.
The software acceleration that this package provides is horrible;
generally we consider it a bug if this is installed.

We will test disabling all the above packages post-alpha-1, and then
make a formal evaluation prior to alpha-2.  Even if we end up disabling
them, we can always easily restore them even post-release.

The one concern is if dropping swx11 would make the LTS backport more
challenging.  However, this will become obvious enough once we've made
the change.  If it does and there's no way around it, we will re-enable
it at that point.


== Various Proposed Patches ==

#993427 - Fixes -fglrx in quantal.  It broke with the new kernel.
Bryce took the action on this.

#1002224 - Enable gallium vdpau.  We'll go ahead and do this post-alpha1
and then re-evaluate it at alpha2.

#610206 - Compile-in the input drivers for boot speed as per Meego.  Not
really sane to do for non-embedded use cases.  tjaalton took action to
wontfix this.

CVE patches - Bryce took action to coordinate with security team on
ownership of tasks for resolving these.


== Intel GPU lockups in Precise ==

Timo has been studying Ivy Bridge gpu freezes.  The next precise kernel
update closes at the end of next week, so we have a window for getting
drm fixes proposed.  He plans to continue testing in this area.  Help
would be appreciated from anyone who can reproduce GPU lockups and is
willing to do some git bisection work on the kernel.


Bryce