Created attachment 135376 [details]
Modifyed example, to repeat bug

Hello!
I'm trying to learn OpenCL, and in this case I'm interested in interacting with LibVA. And it seems to have found a bug. To repeat the bug, I wrote an example, libva_buffer_sharing.cpp. The meaning is that by the operation of the function clCreateBufferFromLibvaIntel, the bytes are very interestingly mixed.

To restore them, for the image, with a width of 640px, I was able to do this:

  staus = clEnqueueReadBuffer (q, resmem, CL_TRUE, 0, total, datat, 0, NULL, NULL);
  CHECK_CLSTATUS (staus, "clEnqueueReadBuffer");

  QFile f ("/ home / nick1710 / testimg2a.pgm");
  f.open (QFile :: WriteOnly);
  f.write ("P5 \ n640 1440 \ n255 \ n");

  for (int j = 0; j <640 * 480 * 3; j + = (640 * 32)) {
    for (int n = 0; n <32; ++ n) {// 0x200 / 0x10 (512/16)
        for (int k = 0; k <(640/16); ++ k) {
            f.write (& datat [j + (k * 512) + (n * 16)], 16);
        }
    }
  }
  f.close ();

ie the first 640 bytes, have blocks of 16 bytes in steps of 512 bytes.
Next, 640, in the same memory, with a 10-byte offset.
And so on, 32 times.
Then the next blended block begins.

I wanted to use this memory object with OpenCV, but convertFromBuffer to UMat object, requires the CL_MEM_OBJECT_BUFFER memory type, by this reason try use this function.

The function, clCreateImageFromLibvaIntel work fine.
In archive i am, also attach sample pgm images.

CPU: Intel Core i3-6098P (SkyLake)
GPU: Intel HD Graphics 510
Motheboard: Gidabyte GA-H110M-S2V
OS: Ubuntu 17.10, Beignet 1.3.1 from repo, and from sources, also Beignet 1.3.2.