AMDVLK 2021.Q2.2 Driver Is Re-Compiled And Re-Released
AMD has released new binary versions their AMDVLK 2021.Q2.2 driver that was originally released on April 28th. We have no idea what, if anything, is different in the new re-release, We can only speculate that the only change in the re-release is that the "new" version is compiled with an updated version of AMD's LLVM compiler fork.
AMD has made new, updated binary Debian and RedHat RPM packages for version 2021.Q2.2 of their AMDVLK Vulkan driver for AMD graphics cards available at github.com/GPUOpen-Drivers/AMDVLK/releases/tag/v-2021.Q2.2.
Both the new and the new AMDVLK 2021.Q2.2 releases have the exact same package names, and both produce the exact same
vulkaninfo output (apiVersion 4202670/1.2.174 and driverVersion 8388792/0x8000b8). They sha256sum differs, and so do the binary libraries within them.
The release notes remain the same as they were when 2021.Q2.2 was first released on April 28th. The old release notes mention that the Vulkan apiVersion (from the Vulkan headers) was bumbed to 1.2.17, that color writes can be enabled dynamically and that there were three minor bug-fixes relating to DCC color compression, the AMD switchable graphics layer being ignored in some cases and out of memory errors if AMDVLK is installed on a machine with no AMD GPU.
We can only make an educated guess as to why version 2021.Q2.2 was re-released since there is no mention of it what so ever on the release page. AMD replaced the release packages and called it a day. Our educated guess is that AMD re-compiled it with an updated version of their LLVM compiler fork due to some bug in it that made it produce unfortunate binary code that negatively impacted AMDVLK drivers behavior.
The binary AMDVLK releases are built from four different repositories:
- github.com/GPUOpen-Drivers/llvm-project/ - A special AMD LLVM fork
- github.com/GPUOpen-Drivers/llpc/ - LLPC, a LLVM-Based Pipeline Compiler maintained by AMD
- github.com/GPUOpen-Drivers/pal - PAL, AMD's Platform Abstraction Library
- github.com/GPUOpen-Drivers/xgl - XGL, the actual Vulkan API layer that translates Vulkan API commands into platform-independent PAL commands.
There has not been any commits to the XGL and PAL repositories since 2021.Q2.2 was first released on April 28th. Those would be the AMDVLK API layer (XGL) and the platform abstraction layer XGL passes the Vulkan API calls on to (as PAL calls). There have, on the other hand, been many changes to the LLPC pipeline compiler and quite a few to AMD's LLVM fork, including some upstream ones that are specific to the LLVM AMDGPU support. This is why we are guessing that AMD re-compiled and re-released AMDVLK 2021.Q2.2 due to some unfortunate bi-effect of a bug in their LLVM fork and/or their LLPC pipeline compiler that's now been fixed.
You can acquire the new binary blob packages for Ubuntu (.deb) and RedHat/Fedora (.rpm) from github.com/GPUOpen-Drivers/AMDVLK/releases/tag/v-2021.Q2.2.