All games maded with Unity engine crashes on AMD GPU, but worked on Intel GPU on same machine

Unity Engine
,
1

All games maded with Unity engine crashes on AMD GPU, but worked on Intel GPU on same machine.

Discussion in amd-gfx mailing list

2

This looks like a driver crash in free/delete after mesa_glsl_link_shader.
I don’t believe that Unity is duplicating these symbols (as concluded in the freedesktop thread) - as far as I can tell, this is all in the radeonsi driver.

3

Valgrind doesn’t show any memory-related issue with Mesa. It does show
an issue with “New Unity Project”. This can corrupt the heap and cause
a random crash on the next call of malloc/free/new/delete:

3377545–264984–valgrind.txt (1.58 MB)

4

We’ll investigate, but if that were the case, wouldn’t it affect the intel driver the same way?

5

Marek said:

There are several factors making radeonsi more vulnerable to heap corruption:

  • radeonsi has a lot of running threads, unlike intel
  • radeonsi uses LLVM, which is a big user of new/delete to the extent of making new/delete/malloc/free a little slower for Mesa and Unity.

Closed-source drivers use their own allocator for memory allocations (usually jemalloc), so they are immune to such Unity bugs.