The function intelEmitCopyBlitLocked() (in file intel_batchbuffer.c) expects source and destination pitch in pixels, but the call from do_draw_pix() (in file intel_pixel.c) retrieves the screen's pitch via intel->intelScreen->front.pitch, which is specified in bytes. The same problem is also evident in intelTryReadPixels().
fixed in mesa_7_0_branch (3ed89025f3df9e72afe0a77c847aab13b2ee861b)
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