Cosmic Apps using wgpu fail with Nvidia graphics.

[XV-02]

I stumbled on this while testing both Cosmic-Edit and Cosmic-Term, on a System76 Gaze17 and a Galp5-1650ti.

Both applications functioned as expected in Pop with Gnome sessions (both X org and Wayland) in all three graphics modes provided by system76-power - Integrated, Hybrid, and Discrete.

In a Cosmic session, the applications work as expected in Integrated graphics mode. However, in both Hybrid and Discrete mode they both cause a window to be drawn, but are totally non-responsive. The only way to close the window is to manually terminate the process.

After back-and-forth with others, it was suggested that the issue might be wgpu. When both Cosmic-Edit and Cosmic-Term were compiled with the wgpu feature disabled, they functioned without issue in Cosmic session in all graphics modes.

I'm not sure of next-steps for finding debug information, and would appreciate guidance to collect info for this issue.

[XV-02]

Testing this on a desktop with an Nvidia 1080 and running on nouveau drivers, Cosmic-Term and Cosmic-Edit were both fine, despite being compiled with the wgpu feature present.

Attempting to run Cosmic on proprietary Nvidia drivers on 10 series cards on desktops results in a thoroughly unresponsive experience, so I haven't tested Cosmic+Desktop Nvidia+Proprietary Nvidia drivers yet. That's another kettle of fish though.

Still, it suggests this might be more directly linked to Nvidia drivers.

[ids1024]

Apparently this is a known issue with wgpu on recent Nvidia drivers with Wayland. Most likely a driver bug: gfx-rs/wgpu#4775

I can reproduce it on Fedora Rawhide with Gnome Wayland.

[luccahuguet]

pop-os/cosmic-epoch#168 (comment)

I can reproduce #264

and it does work only on integrated graphics. Discrete or hybrid does not.

my system is the following:
OS: Pop!_OS 22.04 LTS x86_64
Host: 80YH Lenovo ideapad 320-15IKB
Kernel: 6.6.6-76060606-generic
Uptime: 12 mins
Packages: 2489 (dpkg), 2 (nix-user), 48 (nix-default), 45 (flatpak), 11 (snap)
Shell: nu 0.88.1
Resolution: 1920x1080
DE: COSMIC
Theme: Adwaita [GTK3]
Icons: Adwaita [GTK3]
Terminal: zellij
CPU: Intel i7-7500U (4) @ 3.500GHz
GPU: NVIDIA GeForce 940MX
GPU: Intel HD Graphics 620

[anarsoul]

The bug has not been reported to NVIDIA, so I doubt that they are aware

[gabriele2000]

I've noticed something really weird... I'm using hybrid GPU mode, of course.
I'm a laptop user.

Since today (an update for cosmic-files, cosmic-term and cosmic-edit dropped, I'm in the staging branch) cosmic apps doesn't run at 0.5FPS but at full speed, with a really funny workaround:

[gabriele2000]

The bug has not been reported to NVIDIA, so I doubt that they are aware

NVIDIA/egl-wayland#72 (comment)
It'll be fixed in v550, coming soon, apparently.

[anarsoul]

NVIDIA/egl-wayland#72 (comment) It'll be fixed in v550, coming soon, apparently.

I don't think it's the same issue. I'm seeing it on Turing GPU (GTX 1650), while the comment says that only pre-Turing GPUs are affected and it should work fine on Turing or later.

[ids1024]

There's been some debate on wgpu about whether or not this is a driver bug, or if wgpu is doing something wrong. The Vulcan spec seems a bit vague. But gfx-rs/wgpu#4967 is meant to fix it, and seems like better approach in general.

[anarsoul]

There's been some debate on wgpu about whether or not this is a driver bug, or if wgpu is doing something wrong.

My understanding is that it's a driver bug, since fences should work just fine.

[luccahuguet]

pop-os/cosmic-epoch#168 (comment)

I can reproduce #264
and it does work only on integrated graphics. Discrete or hybrid does not.
my system is the following:
OS: Pop!_OS 22.04 LTS x86_64
Host: 80YH Lenovo ideapad 320-15IKB
Kernel: 6.6.6-76060606-generic
Uptime: 12 mins
Packages: 2489 (dpkg), 2 (nix-user), 48 (nix-default), 45 (flatpak), 11 (snap)
Shell: nu 0.88.1
Resolution: 1920x1080
DE: COSMIC
Theme: Adwaita [GTK3]
Icons: Adwaita [GTK3]
Terminal: zellij
CPU: Intel i7-7500U (4) @ 3.500GHz
GPU: NVIDIA GeForce 940MX
GPU: Intel HD Graphics 620

I can no longer reproduce this bug

[ryzendew]

apps now render properly but will freeze .. with 550 drivers WGPU_BACKEND=gl fixes my apps freezing

[ryzendew]

https://gitlab.freedesktop.org/xorg/xserver/-/merge_requests/967#note_2258144 Confirmed a Driver Bug not a WGPU bug and An nvidia Dev will take a look at the issue! see it helps to report things instead of whining on discord when someone tries to help

[ryzendew]

As of the newest stable driver this no longer happens and can be closed @Drakulix

[soucosmo]

WGPU_BACKEND=gl

Thanks, its worked for me.