[dxvk] Hold a reference to the DxvkAdapter's DxvkInstance

[aeikum]

This fixes a crash when playing Beat Saber with Wine's DXGI.

[aeikum]

To elaborate a bit more.

• When using Wine's DXGI, D3D11CoreCreateDevice creates a DxvkInstance and holds a ref to it.
• DxvkInstance::findAdapterByLuid returns a DxvkAdapter which holds a raw pointer to that DxvkInstance.
• The DxvkAdapter is passed to D3D11DXGIDevice and persists.
• At the end of the function, the original ref is dropped, so the DxvkInstance is destroyed.
• The DxvkAdapter now holds an invalid pointer.

[doitsujin]

I see the problem and wonder why we haven't run into this earlier since it's a really dumb bug; unfortunately this solution creates a circular reference since DxvkAdapter is owned by DxvkInstance, so neither object will ever be destroyed.

I'll work out why there's an adapter->instance relation in the first place, it probably shouldn't exist.

[misyltoad]

Could solve this the d3d9 surface/texture way and make that child object inherit the refcount of its parent

[doitsujin]

Doesn't really work that way since this isn't COM ref counting that's going wrong but the internal DXVK stuff.

Now that I think about it, I think DxvkInstance didn't own its adapters originally but created them on demand, not entirely sure why that has changed.

[aeikum]

I see the problem and wonder why we haven't run into this earlier since it's a really dumb bug;

FWIW the crash I saw happens when Proton's vrclient.ivrcompositor_submit_dxvk calls IDXGIVkInteropDevice::GetVulkanHandles. It crashed in that function once, but much more often it returns a bogus VkInstance, which we then crash on later. We didn't see any other crashes when using Wine's DXGI with DXVK in all of our release testing this cycle.

[doitsujin]

Beat Saber works with the above commit on my end; a proper solution will require significantly more work.

[aeikum]

Thanks. I picked that commit on top of 1.4.4 and confirmed it's working here. Are you OK with releasing like that in the next Proton?

[doitsujin]

Yes; I don't know how long it'll take to rework the whole adapter thing.