<html> <head> <base href="https://bugs.freedesktop.org/"> </head> <body> <div> <a class="bz_bug_link bz_status_NEW " title="NEW - [cfl] GPU hang when running UE4Editor" href="https://bugs.freedesktop.org/show_bug.cgi?id=110228#c30">Comment # 30</a> on <a class="bz_bug_link bz_status_NEW " title="NEW - [cfl] GPU hang when running UE4Editor" href="https://bugs.freedesktop.org/show_bug.cgi?id=110228">bug 110228</a> from <a class="email" href="mailto:jason@jlekstrand.net" title="Jason Ekstrand <jason@jlekstrand.net>"> Jason Ekstrand</a> <pre>Put a bit more time into it. Here's what I have so far: 1. Inserting a barrier() does nothing 2. Setting MOCS = 0 on the buffer used for the atomic makes than hang go away. 3. If I hack up the driver to use an untyped atomic instead of a typed atomic, no change. It still hangs so typed vs. untyped doesn't seem to matter. 4. If I hack the driver up to use SUFTYPE_1D instead of SURFTYPE_BUFFER for the uniform texel buffer, the hang goes away. 5. If I use SURFTYPE_1D for the VkBufferView with the atomic and SURFTYPE_BUFFER for the uniform texel buffer, it hangs. It's very much starting to look like it's just a weird interaction between atomics, the L3$, and the sampler with SURFTYPE_BUFFER. Unfortunately, that means our options for mitigating it are somewhat limited. We can't just use SURFTYPE_1D for all buffer textures because that has a limited width of 16K and I really don't want to start disabling L3 caching on all atomics.</pre> </div> <hr> You are receiving this mail because: <ul> <li>You are the assignee for the bug.</li> <li>You are the QA Contact for the bug.</li> </ul> </body> </html>