FWIW, I'm aware of the alt+tab hang but not sure what's causing it, and debugging this is a huge pain in the arse so I kinda gave up on it. At the time I wasn't able to get UMR dumps either, all I know is that it's not a recent regression and has been a thing since at least 2.4, if not earlier.
I know is that it's not a recent regression and has been a thing since at least 2.4, if not earlier.
The post on reddit mentioned that the problem apparently doesn't exist on "the Proton version that added support for the game", so I asked which one they mean exactly. Maybe i'll try to bisect this then starting with DXVK from that proton version.
Not sure how useful that is tbh, old DXVK versions tend to not build on current compilers and things have moved on a little in the past 6 or so years. I'd rather revisit this at some time when debug tools actually work, it's not an urgent issue anyway, users can throw gamescope at the problem for now.
Happens to me in No Man's Sky in one specific place
RADV_DEBUG=hangx1 2025-03
This reddit post made me try it out: https://reddit.com/r/linux_gaming/comments/1j0fwjc/final_fantasy_xv_is_unplayable_on_linux/
FFXV seems to reliably hang the GPU if you alt+tab in and out a few times while in the open world. This happens with both RADV and AMDVLK. Using RADV_DEBUG=hang or having vulkan validation layers enabled seems to work around it, but there are no validation errors (note that Arch' VVL package seems broken at the moment and fails to load due to undefined symbols, i had to build it manually adding -D UPDATE_DEPS=ON to the cmake option in the PKGBUILD).
RADV prints this in the log:
However, the dmesg it looks like FFXV is causing the hang after all?
I tried this on both KDE and gnome (wayland).
To reproduce, start a new game in the demo, skip cutscenes, run around in the open world for a bit and then alt+tab in and out a few times.
I realize this might not be a DXVK issue, but I'm unsure how to properly narrow this down, so maybe you can take a look?
Software information
FFXV Demo
System information
Apitrace file(s)
Log files
steam-671210.log