Bug#769072: Bug#769191: xorg: apt-get dist-upgrade somehow reconfigured my system to use the nvidia driver, even though I have no nvidia hardware

[Simon McVittie]

On Wed, 12 Nov 2014 at 02:08:34 +0000, Nathaniel J. Smith wrote:
> This evening I ran 'apt-get dist-upgrade' on my 'testing' system, rebooted, and
> found the system unusable -- it just came up with gdm3's "Oh no! Something has
> gone wrong!" screen.
> 
> It turns out that the problem is that somehow, dist-upgrade reconfigured X to
> use the nvidia drivers for GLX -- e.g., from /var/log/messages:
> [...]
> Nov 12 01:47:35 branna gdm-Xorg-:0[4239]: (EE) Failed to initialize GLX
> extension (Compatible NVIDIA X driver not found)

This sounds somewhat similar to #769072 (which is currently assigned to
gnome-shell, and I only haven't reassigned it away because I'm not sure which
nvidia-related package has the bug). The exact symptom is different,
but the high-level situation ("trying to use a mixture of Mesa and nVidia
GL stuff after an upgrade") is similar. Perhaps they should be merged?

Finding the offending upgrade in /var/log/apt would be useful;
so would the details of the apt transaction(s) in which you removed
the nvidia stuff.

Michael, I assume you have out-of-band information that says #769481 is
in fact the same as #769191? (I ask because you merged them, but it isn't
obvious why from the bug log.)

    S