[Xen-users] Why is GPU passthrough so difficult?

["Kent R. Spillner" <kspillner@xxxxxxx>]

Why is GPU passthrough so difficult?  I saw a note on the wiki about GPU 
passthrough which mentioned the fact that modern video cards perform a lot of 
different functions and maintain a lot of state, but I couldn't find any 
details about why GPU passthrough is more difficult compared to other PCI 
devices.

It seems that even with two separate GPUs it's still tricky to get things 
working.  Are the main challenges in the drivers, or in the kernel, or in the 
way BIOS/UEFI initializes video cards, or some combination of all of these 
things?  Or, dare I ask, is it the GPU vendors trying to upsell more 
"enterprise" hardware?

I'm just curious to learn more about the underlying technical challenges around 
GPU passthrough in general.  Thanks in advance for any explanation or pointers!



_______________________________________________
Xen-users mailing list
Xen-users@xxxxxxxxxxxxx
https://lists.xen.org/xen-users