Cooperative Bug Isolation for Fedora 13


The Cooperative Bug Isolation Project (CBI) is now available for Fedora
13. CBI (http://www.cs.wisc.edu/cbi/) is an ongoing research effort to
find and fix bugs in the real world. We distribute specially modified
versions of popular open source software packages. These special
versions monitor their own behaviour while they run, and report back how
they work (or how they fail to work) in the hands of real users like
you. Even if you’ve never written a line of code in your life, you can
help make things better for everyone simply by using our special
bug-hunting packages.

We currently offer instrumented versions of Evolution, The GIMP, GNOME
Panel, Gnumeric, Liferea, Nautilus, Pidgin, Rhythmbox, and SPIM.
Download at <http://www.cs.wisc.edu/cbi/downloads/>. We support
PackageManager, yum, apt, and many other RPM updater tools; see
<http://www.cs.wisc.edu/cbi/downloads/repo-config.html> for customized
configuration help for any of our supported distributions and updater
tools. Or just download and install
<http://www.cs.wisc.edu/cbi/downloads/rpm/fedora-13-i386/RPMS.tools/cbi-package-config-13-10.i686.rpm>
to automatically configure most popular RPM updaters to use the CBI
repository.

It’s that easy! Tell your friends! Tell your neighbours! The more of
you there are, the more bugs we can find.

We still offer CBI packages for earlier releases as well, going all the
way back to Fedora 1. When and if you decide to upgrade to Fedora 13,
we’ll be ready for you. Until then, your participation remains valuable
even on older distributions.

Via Dr. Ben, the CBI guy

Ubuntu 10.04 memory leak issue: Not RedHat’s nor Fedora’s fault


Some of you may have read about a memory leak that cropped up very late in Ubuntu 10.04 development
process. They kindly put this phrase in their explanation of the bug:

“One possible solution is to roll back the GLX 1.4 enablement patches,
and the patch which caused the memory leak to appear. These GLX patches
were produced by RedHat and incorporated into Debian, they were not
brought in due to Ubuntu-specific requirements”

Which can obviously create the impression that the patches in question
actually come from Red Hat Enterprise Linux, or from Fedora.

Short story for the impatient: the problematic patch is not in any
version of Fedora and never has been, Fedora is not subject to this
memory leak and never has been.

So if you see any stories drawing the implication that Fedora is also
subject to this leak, please (VERY KINDLY!!!) correct them – it isn’t.

Longer version for the curious: I’m not sure about the claim that the
‘GLX 1.4 enablement patches’ come from Red Hat, they may be in RHEL for
some reason, but they’re not in Fedora; we wouldn’t need to backport GLX
1.4 from X server 1.8 to 1.7 as we’re just shipping X server 1.8 in
Fedora 13 anyway.

Regardless, the actual patch that caused the problem in Ubuntu was not
part of the GLX 1.4 backport, but was an attempt to fix this bug:

https://bugs.freedesktop.org/show_bug.cgi?id=26394

Sometimes X would crash when Clutter-based apps closed. Fedora did
actually suffer from this bug too:

https://bugzilla.redhat.com/show_bug.cgi?id=579756

However, Ubuntu and Fedora took different approaches to fixing it.
Ubuntu seems to have jumped on one of Jesse Barnes’ early attempts to
fix the problem (Jesse works for RHT, hence the Red Hat link Intel). In the
end, though, if you read the upstream bug, Jesse ceded to Kristian
Høgsberg (who worked at Red Hat until recently and now, for the record, works for Intel), who provided a better fix which was committed to upstream. For Fedora 13, we took Kristian’s fix, not any of Jesse’s attempts. This was included in xorg-x11-server-1.8.0-7.fc13 . That seems to have caused a couple of
problems with compositing managers:

https://bugzilla.redhat.com/show_bug.cgi?id=584832
https://bugzilla.redhat.com/show_bug.cgi?id=577142

xorg-x11-server-1.8.0-7 was sent as a candidate update for F13, got bad Bodhi feedback (as
you’d expect) and was withdrawn; it never went into the ‘stable’ F13
repo (the one from which the final F13 will actually be built). The bugs
were fixed by adding one more upstream patch, from Michel Dänzer:

http://cvs.fedoraproject.org/viewvc/rpms/xorg-x11-server/F-13/xserver-1.8.0-dri2-fix-handling-of-redirected-pixmaps.patch?view=markup

to xorg-x11-server-1.8.0-8.fc13 . That build has good feedback:

https://admin.fedoraproject.org/updates/xorg-x11-server-1.8.0-8.fc13

and was pushed to F13 updates two days ago. So in summary our processes
worked very well, we didn’t jump on an incomplete fix, we didn’t push
the initial upstream fix to the ‘stable’ F13 because our feedback system
made us aware of the problems it caused, we did push the fully-working
fixed package when it was confirmed ready, and we were never at any
point subject to the memory leak issue. This is actually quite a nice
story of our QA processes working effectively, if someone’s looking for
such a thing. =)

I plagiarized much of this from an email I got from
Adam Williamson [I think its plagiarize Adam day :)] because I thought it would be good to set the record strait and I really don’t know a whole lot about the areas this happened in. So record is set strait, if you do correct any stories please be really nice about, there is a lot of FUD (whether its intentional or not) and that always makes it hard to report the truth.

Also if you want to make reporters lives awesome you should read over Zonker’s Fedora Classroom Log really awesome stuff. https://fedoraproject.org/wiki/Classroom#Apr_27_2010_.2820100427.29