1 Reply Latest reply on Jan 30, 2017 10:39 AM by kingfish

    Direct3D 12 Shared Heap Issue (mGPU) [Crimson Driver Package 16.12.x+]


      About a month ago I ran into an issue with our current build that supports Multi-Adapter via Direct3D when using Shared Heaps.

      As Microsoft also decided to push out a new Windows SDK, Visual Studio Update and Windows 10 Build all at the same time as Crimson ReLive, well it's been a pain to actually figure out which of these exactly caused the issue in the first place.


      More so as I've discovered that it was the Crimson (Software) Driver Package not the Display Driver itself, as Package 16.6 (16.9.x Release) and 16.11 (16.11.1 Release) both work, this is exclusive to the 16.12 Package (thus affects 16.12.1, 16.12.2 and 17.1.1; the later however can be installed on-top of Package 16.6 which is how I discovered this wasn't the Driver but the Driver Package causing this issue).


      The issue itself is when creating a Shared Heap between Devices, AMDXC64.DLL triggers an Access Violation (0xC0000005) Exception (Locked Memory?) and it does this very consistently at Address 0x0030. (See Screenshot)


      Now this issue wasn't with how own specific implementation (thus you can use the Microsoft DirectX Sample - D3D12HeterogeneousMultiadapter for Testing Purposes).

      Unfortunately all I have for testing is an A10-PRO 7850K + R7 360, and the various test Machines the team have are again APU + 300-Series GPU; all of which are exhibiting identical Access Violation Errors. So I'm not sure if this is an issue with the APU Graphics, 300-Series, etc.

      I'm also not sure how many other Developers are actually focused on utilising Multi-Adapter with Shared Heaps over the more Traditional Crossfire (AFR) Approach and Dedicated Heaps (which work fine) or this particular approach.


      Radeon Software Version - 16.12.2 (Access Violation) / 16.6 (Works)

      Radeon Software Edition - Crimson (ReLive)

      Graphics Chipset - AMD Radeon (TM) R7 360 Series

      Memory Size - 2048 MB

      Memory Type - GDDR5

      Core Clock - 1060 MHz

      Windows Version - Windows 10 Pro (64 bit) [14393.693]

      System Memory - 16 GB

      CPU Type - AMD A10-7850K Radeon R7, 12 Compute Cores 4C+8G