[elrepo] NVIDIA and RHEL 6.5 issue (libglamoregl)

[Manuel Wolfshant]

On 11/30/2013 03:30 PM, Phil Perry wrote:
> Hi all,
>
> I just wanted to bring to the attention of NVIDIA users one potential 
> issue with the release of RHEL6.5 and NVIDIA proprietary drivers.
>
> Taken from the NVIDIA changelog for the 304.xx release:
>
>     * Updated nvidia-installer to consider the "libglamoregl.so" X 
> loadable
>       extension module to be in conflict with the NVIDIA OpenGL 
> driver. This
>       module can cause the NVIDIA libGL to be loaded into the same 
> process
>       (the X server) as the NVIDIA libglx.so extension module, which 
> is not
>       a supported use case.
>
>
> So we see the Xorg glamoregl lib is not compatible with the NVIDIA 
> drivers.
>
> This wasn't previously an issue for us because libglamoregl wasn't 
> included with Xorg that shipped with RHEL. However, updating to 
> RHEL6.5 now pulls in the xorg-x11-glamor package:
>
> $ rpm -ql xorg-x11-glamor
> /usr/lib64/libglamor.so.0
> /usr/lib64/libglamor.so.0.0.0
> /usr/lib64/xorg/modules/libglamoregl.so
> /usr/share/X11/xorg.conf.d/glamor.conf
> /usr/share/doc/xorg-x11-glamor-0.5.0
> /usr/share/doc/xorg-x11-glamor-0.5.0/COPYING
> /usr/share/doc/xorg-x11-glamor-0.5.0/README
>
>
> As we see above, the package installs a conf file at 
> /usr/share/X11/xorg.conf.d/glamor.conf which loads the Xorg module:
>
> $ cat /usr/share/X11/xorg.conf.d/glamor.conf
> Section "Module"
>         Load  "dri2"
>         Load  "glamoregl"
> EndSection
>
>
> $ cat /var/log/Xorg.0.log | grep glam
> [    25.241] (II) LoadModule: "glamoregl"
> [    25.262] (II) Loading /usr/lib64/xorg/modules/libglamoregl.so
> [    25.696] (II) Module glamoregl: vendor="X.Org Foundation"
>
>
> As glamoregl conflicts with NVIDIA drivers we need to prevent this 
> happening. Our choices are:
>
> 1. We could manipulate the /usr/share/X11/xorg.conf.d/glamor.conf file 
> to prevent the lib from loading by either editing it or 
> renaming/moving the conf file. However, this has the disadvantage that 
> updates to the distro xorg-x11-glamor package can undo our work so 
> this probably isn't the best approach.
>
> 2. We could uninstall the conflicting xorg-x11-glamor package. Lets 
> look at the dependencies to see how it ended up being installed in the 
> first place:
>
> The package xorg-x11-drivers is installed by default on systems with 
> Xorg installed. It is a dummy package that pulls in all xorg-x11-drv-* 
> driver packages as dependencies. One of those packages is 
> xorg-x11-drv-ati and that Requires xorg-x11-glamor:
>
> # rpm -q --requires xorg-x11-drv-ati | grep glam
> libglamor.so.0()(64bit)
>
> So as we would expect:
>
> # yum erase xorg-x11-glamor
> <snip>
>
> Dependencies Resolved
>
> ========================================================
>  Package          Arch   Version                    Repository Size
> ========================================================
> Removing:
>  xorg-x11-glamor  x86_64 0.5.0-6.20130401git81aadb8.el6
>
> @rhel-x86_64-server-6 226 k
> Removing for dependencies:
>  xorg-x11-drivers x86_64 7.3-13.4.el6 @rhel-x86_64-server-6 0.0
>  xorg-x11-drv-ati x86_64 7.1.0-3.el6 @rhel-x86_64-server-6 478 k
>
> Transaction Summary
> ========================================================
> Remove        3 Package(s)
>
> Installed size: 703 k
> Is this ok [y/N]:
>
>
> Personally I would prefer to see users uninstall those packages. This 
> would be my recommendation.
In an ideal world, that would be the best option from my point of view, 
too. But....

>
> The question is whether we recommend this action or whether we enforce 
> it by placing a Conflicts in the nvidia-x11-drv package conflicting 
> with xorg-x11-glamor? This would enforce users to manually uninstall 
> xorg-x11-glamor (and xorg-x11-drv-ati and xorg-x11-drivers) but it 
> will create yum errors either when updating our nvidia packages or 
> when updating to 6.5.
>
> I'd like to hear input from package users on their thoughts on the above.
>
... leaving aside that non-suspecting users will panic seeing 
"xorg-x11-drivers " as recommended for erasure ( most people have no 
idea that it's just a meta-package requiring all the drivers ) I am torn 
between two problems:
- I'd rather add a "Conflicts:" in nvidia-X11-drv. Simply recommending 
the removal of xorg-x11-glamor won't fly for a simple reason: in real 
life, no one reads the docs :) unless they are forced to
- on the other hand, this approach will prohibit simultaneous 
installation of both NVidia and ATI drivers. Believe it or not, I did 
have cases ( rare, but they existed) when I relocated a hard disk 
between a PC with one type of card to one with the other. Or simply 
replaced the video card. Being able to just change the config file for X 
and have a functional system was a nice feature.
     Whatever the chosen approach is, we will need to add a README in 
the nvidia-x11-drv package, explaining the issue.

As a personal note: having the config file for glamor placed below /usr 
is an error from my point of view, unless there is a way to force NOT 
loading it via a config file placed in /etc/X11/xorg.conf.d ( where 
config files should be in the first place )


> WRT the conflict, I haven't been able to observe any detrimental 
> affects having libglamoregl.so loaded. Simple OpenGL tests such as 
> glxgears still run and I see no errors in my Xorg log file, so this 
> isn't a show stopper that is going to instantly crash X for everyone. 
> ATM I have no idea how to trigger an issue related to this so I would 
> classify the urgency as low.
>
> Phil

     wolfy (for who flash does not work correctly with NVidia's blob)