AnsweredAssumed Answered

row_pitch error with CL_MEM_USE_HOST_PTR

Question asked by stoney on Dec 21, 2012
Latest reply on Jan 9, 2013 by stoney

I'm using an AMD Radeon HD 7970 (just installed and updated) on Windows 7-64, AMD Catalyst 12.11.


In clCreateImage2D, when using CL_MEM_USE_HOST_PTR, all but one of the implementations I've tried allows passing a row_pitch that is greater than the number of pixels in a row, so long as row_pitch is a multiple of the pixel size.


With the AMD Radeon HD 7970, the excess row_pitch is not ignored, so that the resultant image is skewed. IOW, it's treating the data past the end of each host row as part of the image.


On Mac, I've tested an AMD Radeon HD 5870 and an nVidia GeForce GT 650M, which behave properly. On Windows, I've tested an nVidia GeForce GTX 680, which worked fine, and the AMD 7970, which didn't. Interestingly, the AMD CPU OpenCL implementation works properly on Windows.


It does not fail when using CL_MEM_COPY_HOST_PTR, or when not supplying the host pointer and calling enqueueWriteImage to copy the data.


This is clearly a bug, but I'm not sure how to report it, or if I just did that.


I can supply a snippet of source code if necessary.