Red Hat Bugzilla – Bug 1273131
clGetPlatformIDs causes futex race condition
Last modified: 2016-02-07 13:31:39 EST
User-Agent: Mozilla/5.0 (X11; Fedora; Linux x86_64; rv:41.0) Gecko/20100101 Firefox/41.0
Apologies if I've mischaracterised anything above, I'm going off of my uninformed analysis of the attached backtrace from GDB.
Attempting to use Blender in any meaningful way results in the UI hanging. strace clued me into the blocking futex call and gdb seems to point the finger at libOpenCL.so.
Oddly enough, clinfo works as it should
Steps to Reproduce:
1. Open Blender
2. Open system tab of preferences panel, switch to the Cycles renderer etc
UI freeze, application hang
Application doesn't hang
rpm -q fedora-release
rpm -q blender
rpm -q ocl-icd
Created attachment 1084465 [details]
Blender GDB backtrace
The backtrace shows that clover is used.
I've tried with a variety of different configurations to check whether this bug might be setup-specific. I normally use two GPUs from mixed vendors, but I tried using a single GTX570, HD6870, HD6950, 9800GT and just the plain Intel HD4000 but still this bug persists
I strongly suspect that it's an issue if clover/mesa's opencl tracker, please file a bug in upstream or retry with the latest release from rawhide.