[Intel-gfx] [PATCH] drm/i915: Disable semaphore on vGPU for now

[Chris Wilson]

Quoting Zhenyu Wang (2019-03-27 09:06:36)
> This is to disable semaphore usage when on vGPU for now. Unfortunately
> GVT-g hasn't fully enabled semaphore usage yet, so current guest with
> semaphore use would cause vGPU failure.
> 
> Although current semaphore failure with vGPU can be simply resolved by
> allowing cmd parser to accept MI_SEMAPHORE_WAIT command with address
> audit, we're checking general usage of semaphore and how we should
> handle it properly for virtualization in consider of function and
> security concern. So we decide to request to disable it for now in
> guest driver. Once GVT could support it, we would add new compat bit
> to turn it on.

MI_WAIT_SEMAPHORE are used by Vulkan (anvil) as well for VkEvents.
-Chris