Bug 4095

Created attachment 2858 [details] [review]
change-default-dri-driver-dir.patch

Um, why /usr/lib/xorg?  If anything, it should be /usr/lib/mesa.  I'm running
with /usr/lib/dri (no /modules/dri, just with the modules straight under
/usr/lib/dri) for the Ubuntu build of Mesa, at least for the time being.

Because the dri modules have historically installed into the dri/ subdirectory
of where all the other X modules go. And they install to /usr/lib/xorg/modules.

Sure, but libGL is no longer being provided by xorg; it's being provided by Mesa
in the modular world, which is a completely separate project to X.Org, and may
well be installed in a separate prefix.  $(xorg_prefix)/lib/xorg/modules
contains modules for the X.Org server; $(mesa_prefix)/lib/dri, presumably,
contains client-side modules for Mesa's libGL.

You do have a point, but I think it will be confusing for people to have 2D
drivers in one place and 3D drivers somewhere completely different when they
used to be in the same place.

They used to be in the same place because the 3D drivers only worked in the X
environment. That's going to change with standalone EGL.

OK then, let's change it to somewhere else. The one thing I can say is that
"/usr/X11R6/lib/modules/dri" isn't the right place. Daniel's suggestion of
/usr/lib/mesa/dri works for me.

I'm not sure it's a good idea for the path to contain 'mesa', as there could be
other drivers in there that don't have much if anything to do with Mesa. FWIW,
/usr/lib/dri sounds good to me.

Of the 3 locations (/usr/lib/xorg, /usr/lib/mesa, /usr/lib/dri), the
one Michel suggested seems to make the most sense to me.  Ultimately,
the DRI isn't X specific, so /usr/lib/dri seems to make the most
sense.

Created attachment 2935 [details] [review]
change-default-dri-driver-dir-2.patch

K, /usr/lib/dri it is.

I think this change should only be done in the modular build system, not in the
monolith. For the monolith we have generally not changed any of the default
paths, but we have done so in the modular tree.

The actual path should be configurable, so a new configure command line switch
will need to be added.

The change is only visible in the modular build system, as I suggested in
comment #0, because the monolith passes -DDEFAULT_DRIVER_DIR as it compiles.

In addition, mesa is an external package from the monolith so it's difficult for
me to justify that it should be obeying everything XOrg does.

Perhaps mesa will at some point accept command-line switches, but for now you
could easily set DEFAULT_DRIVER_DIR as one of the defines in configs/.

But really this is about changing the default, not about all the ways to
configure it that could be added. It doesn't affect the monolith in any way I
can see, so I don't understand that argument.

So why don't we change for 6.[56]?

This got fixed over a year ago after some mailing list discussion and is now ${libdir}/dri.

http://cgit.freedesktop.org/mesa/mesa/commit/?id=5dbbde5b

Mass version move, cvs -> git