Hi Krzysztof,
[...]
> @@ -3375,7 +3360,9 @@ i915_gem_do_execbuffer(struct drm_device *dev,
>
> eb.exec = exec;
> eb.vma = (struct eb_vma *)(exec + args->buffer_count + 1);
> - eb.vma[0].vma = NULL;
> +
> + memset(eb.vma, 0x00, args->buffer_count * sizeof(struct eb_vma));
> +
> eb.batch_pool = NULL;
>
> eb.invalid_flags = __EXEC_OBJECT_UNKNOWN_FLAGS;
> @@ -3584,7 +3571,16 @@ i915_gem_execbuffer2_ioctl(struct drm_device *dev,
> void *data,
> if (err)
> return err;
>
> - /* Allocate extra slots for use by the command parser */
> + /*
> + * Allocate extra slots for use by the command parser.
> + *
> + * Note that this allocation handles two different arrays (the
> + * exec2_list array, and the eventual eb.vma array introduced in
> + * i915_gem_do_execubuffer()), that reside in virtually contiguous
> + * memory. Also note that the allocation doesn't fill the area with
> + * zeros (the first part doesn't need to be), but the second part only
> + * is explicitly zeroed later in i915_gem_do_execbuffer().
I get the gist of this comment, but I think you could reword the
last sentence:
"Also note that the allocation doesn't fill the area with zeros,
because it is unnecessary for exec2_list array, and eb.vma is
explicitly zeroed later in i915_gem_do_execbuffer()."
> + */
> exec2_list = kvmalloc_array(count + 2, eb_element_size(),
> __GFP_NOWARN | GFP_KERNEL);
> if (exec2_list == NULL) {
> --
> 2.45.2
>
--
Best Regards,
Krzysztof
