Re: Mesa vulkan layer path fix for core-updates

[Kaelyn <kaelyn.alexi@protonmail.com>]

Hi,

------- Original Message -------
On Tuesday, April 25th, 2023 at 2:15 PM, Andreas Enge <andreas@enge.fr> wrote:


> 
> 
> Hello Kaelyn,
> 
> thanks for your research!

You're welcome! :)

> Am Wed, Apr 19, 2023 at 04:07:51PM +0000 schrieb Kaelyn:
> 
> > * https://issues.guix.gnu.org/62176 can be closed when core-updates is merged, since core-updates contains mesa 22.2.4
> > * Though not exactly mesa-related, https://issues.guix.gnu.org/61364 can possibly be closed now, and almost certainly once the core-updates merge is completed. (The ticket is a number of workarounds the user applied in early Feb to be able to build their system profile using core-updates, to pick up Mesa 22 for newer hardware support. I'm not sure if any of the patches are still relevant.)
> 
> 
> I just closed these two.
> 
> > * https://issues.guix.gnu.org/58887 looks like an alternate way of solving the layer path issues that https://issues.guix.gnu.org/59453 also addresses. Additionally, it adds two new nonstandard VK_*_PATH variables to vulkan-loader, with at least VK_ILAYER_PATH seeming very similar in functionality to VK_LAYER_PATH and VK_ADD_LAYER_PATH described at https://github.com/KhronosGroup/Vulkan-Loader/blob/main/docs/LoaderInterfaceArchitecture.md
> > * https://issues.guix.gnu.org/58251 would be fixed by https://issues.guix.gnu.org/59453

I feel these two can be closed once 59453 lands, as then the manifests will have the store path to their corresponding shared objects. I also think having the full paths in the manifests will lead to fewer cross-version/cross-package mixing of objects, compared to setting and using environment variables of directories to search.

> > * https://issues.guix.gnu.org/62313 might need a modification to mesa e.g. to add VDPAU_DRIVER_PATH as a native-search-path (one possible solution; in my home profile I made VDPAU work by setting "VDPAU_DRIVER_PATH=/run/current-system/profile/lib/vdpau").
> > * https://issues.guix.gnu.org/48868 appears to be the same VDPAU_DRIVER_PATH issue as https://issues.guix.gnu.org/62313.

For the VDPAU drivers, I plan to do a little more digging and some experimenting but I suspect defining VDPAU_DRIVER_PATH as a native-search-path is the best way forward. I'll send a patch once I've tested a change locally without having my profile set VDPAU_DRIVER_PATH to /run/current-system/profile/lib/vdpau.

Cheers,
Kaelyn
> 
> 
> And leave these to you and anybody who wants to work on them!
> 
> Andreas