Bug 109396

Summary: [radeonsi, regression, bisected, d3d trace] NFS Underground - 18.2.8 render fine, flickering present in 18.3.2
Product: Mesa Reporter: smoki <smoki00790>
Component: Gallium/StateTracker/galliumnineAssignee: mesa-dev
Status: RESOLVED MOVED QA Contact: mesa-dev
Severity: normal    
Priority: medium    
Version: 18.3   
Hardware: x86-64 (AMD64)   
OS: Linux (All)   
Whiteboard:
i915 platform: i915 features:

Description smoki 2019-01-20 05:57:29 UTC 
Current Debian Sid, tested with Kabini hardware... issue with black flickering artifacts in  NFS: Underground game played in Nine, appeared after updating from Mesa 18.2.8 to Mesa to 18.3.2...

 https://packages.debian.org/sid/libgl1-mesa-dri

 I am using what is in distro there, so LLVM is that LLVM 7.0.1-4 and everything else... Long story short, so i bisected this and made a trace as requested on #d3d9 IRC, so first bad is be0bd95abf69920fc11fb50384ffc2f886a5f9e8

 radeonsi: fix GPU hangs with bindless textures and LLVM 7.0

 Trace is here:

 https://www.dropbox.com/s/b1o6emkm6z7hfyu/NFS%3AUnderground.7z?dl=0
Comment 1 Axel Davy 2019-01-20 10:31:25 UTC 
Replaying the trace indeed shows the issue, but after playing with the code a bit, and restoring to initial git state, I cannot reproduce the issue. I guess there must some uninitialized memory access and you can see or not the issue depending on the memory content. Maybe the wrong texture or the wrong address gets sampled ?

But given this, there is a possibility that the bisect may fall on the wrong commit. Are you sure this is this commit ?
Comment 2 smoki 2019-01-20 11:33:32 UTC 
 I am more than absolutely sure that this is a commit... tried even manually to apply be0bd95abf69920fc11fb50384ffc2f886a5f9e8 on top of fa595e3d0c47be1e91d8d24cce90c756fed23044 and issue appear every time.

 Did even cold boots in between :D So i am 101% sure.
Comment 3 Stuart Young 2019-01-20 11:55:27 UTC 
Could this be an LLVM issue like https://bugs.freedesktop.org/show_bug.cgi?id=108594 at all?

I note that the fix for that issue in LLVM hasn't yet made it into the llvm in Debian (via release or distro patch).
Comment 4 smoki 2019-01-20 14:25:11 UTC 
 Well, who knows might be. I will rebuild mesa 18.3.2 against llvm 8 nightly packages from apt.llvm.org and to report if anything happens.
Comment 5 smoki 2019-01-20 14:37:40 UTC 
 Yeah, corruptions disappeared for this bug too with llvm8 trunk instead of llvm 7.0.1 

 llvm8 svn351543 that is i tried now... so likely that is.
Comment 6 smoki 2019-01-20 14:59:01 UTC 
 Actually 18.3.2 and llvm 8 does not like each other, throwing in console:

 '+vgpr-spilling' is not a recognized feature for this target (ignoring feature)

 So take previous comment as grain of salt :D
Comment 7 smoki 2019-01-20 15:33:40 UTC 
 But mesa master likes that llvm 8. And what that means? 

 Essentially nothing as current releases ara unusable. I will close bug when current releases become usable.
Comment 8 smoki 2019-01-20 15:53:12 UTC 
 Git unrelease fixed, so closing.
Comment 9 GitLab Migration User 2019-09-18 17:53:20 UTC 
-- GitLab Migration Automatic Message --

This bug has been migrated to freedesktop.org's GitLab instance and has been closed from further activity.

You can subscribe and participate further through the new bug through this link to our GitLab instance: https://gitlab.freedesktop.org/mesa/mesa/issues/126.

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