|Summary:||[Polaris] Glitches in New Super Mario Brothers U in Cemu on Polaris and Tahiti (maybe more)|
|Product:||Mesa||Reporter:||John Galt <johngaltfirstrun>|
|Component:||Drivers/Gallium/radeonsi||Assignee:||Default DRI bug account <dri-devel>|
|Status:||NEEDINFO ---||QA Contact:||Default DRI bug account <dri-devel>|
|i915 platform:||i915 features:|
dmesg from boot to the issue
screenshot of the issue
Description John Galt 2018-10-10 15:25:05 UTC
Created attachment 141980 [details] dmesg from boot to the issue This is a semi recent (within the last few months) bug on Polaris in NSMBU. Many polygons (maybe?) have major glitches across the screen, or don't show up at all. This doesn't occur on Tahiti or Pitcairn. I've gone back to 18.2.1 and verified it still exists, so it must be prior. It also exists on both linux 4.18.12 and the amdgpu-staging-drm-next branch. I'll continue attempting to bisect, unless someone else knows exactly what the issue is. There are quite a few GPU faults listed in the attached dmesg, though I'm not sure if they're related to the issue. Glxinfo, Xorg.0.log, as well as a screenshot of the issue.
Comment 3 John Galt 2018-10-10 15:26:56 UTC
Created attachment 141983 [details] screenshot of the issue
Comment 4 John Galt 2018-10-10 15:29:22 UTC
I forgot to mention, if IRC works better for communication for anyone, I'm TheRealJohnGalt on Freenode #radeon.
Comment 5 John Galt 2018-10-10 20:04:39 UTC
I was incorrect, this also happens on Tahiti now.
Comment 6 Alex Deucher 2018-10-10 20:08:10 UTC
Seems more likely to be an LLVM or Mesa bug than a kernel one.
Comment 7 John Galt 2018-10-10 20:21:03 UTC
(In reply to Alex Deucher from comment #6) > Seems more likely to be an LLVM or Mesa bug than a kernel one. I went back to 4.18.7 and it persisted, so you're correct. It was okay early on at 18.2.0 with llvm svn. I'll go back to 18.2.0 to test, and if it's broken then we know it's llvm.
Comment 8 John Galt 2018-10-10 20:41:29 UTC
I attempted to bisect in Mesa, and found that I wasn't able to get rid of the glitch. The regression must be in LLVM.
Comment 9 John Galt 2018-10-25 14:46:35 UTC
R600_DEBUG=nir works around this issue. If requested, I can provide apidoc of this rendering issue.
Comment 10 Timothy Arceri 2019-07-03 00:39:06 UTC
Is this still an issue with the development version of LLVM 9.0 ? There have been many LLVM bug fixes since this issue was reported.