On Fri, Jul 28, 2023 at 06:35:12PM -0700, Sean Christopherson wrote:
> Move the check that a vGPU is attacked from is_2MB_gtt_possible() all the
typo: "attacked" --> "attached"
> way up to shadow_ppgtt_mm() to avoid unnecessary work, and to make it more
This commit message does not match to what the patch does.
The check in the patch is in ppgtt_populate_shadow_entry().
What you want is like below?
@@ -1796,6 +1797,9 @@ static int shadow_ppgtt_mm(struct intel_vgpu_mm *mm)
if (mm->ppgtt_mm.shadowed)
return 0;
+ if (!test_bit(INTEL_VGPU_STATUS_ATTACHED, vgpu->status))
+ return -EINVAL;
+
mm->ppgtt_mm.shadowed = true;
for (index = 0; index < ARRAY_SIZE(mm->ppgtt_mm.guest_pdps); index++) {
> obvious that a future cleanup of is_2MB_gtt_possible() isn't introducing a
> bug.
>
> is_2MB_gtt_possible() has only one caller, ppgtt_populate_shadow_entry(),
> and all paths in ppgtt_populate_shadow_entry() eventually check for
> attachment by way of intel_gvt_dma_map_guest_page().
>
> And of the paths that lead to ppgtt_populate_shadow_entry(),
> shadow_ppgtt_mm() is the only one that doesn't already check for
> INTEL_VGPU_STATUS_ACTIVE or INTEL_VGPU_STATUS_ATTACHED.
...
> diff --git a/drivers/gpu/drm/i915/gvt/gtt.c b/drivers/gpu/drm/i915/gvt/gtt.c
> index 5426a27c1b71..2aed31b497c9 100644
> --- a/drivers/gpu/drm/i915/gvt/gtt.c
> +++ b/drivers/gpu/drm/i915/gvt/gtt.c
> @@ -1163,8 +1163,6 @@ static int is_2MB_gtt_possible(struct intel_vgpu *vgpu,
> if (!HAS_PAGE_SIZES(vgpu->gvt->gt->i915, I915_GTT_PAGE_SIZE_2M))
> return 0;
>
> - if (!test_bit(INTEL_VGPU_STATUS_ATTACHED, vgpu->status))
> - return -EINVAL;
> pfn = gfn_to_pfn(vgpu->vfio_device.kvm, ops->get_pfn(entry));
> if (is_error_noslot_pfn(pfn))
> return -EINVAL;
> @@ -1277,6 +1275,9 @@ static int ppgtt_populate_shadow_entry(struct intel_vgpu *vgpu,
> if (!pte_ops->test_present(ge))
> return 0;
>
> + if (!test_bit(INTEL_VGPU_STATUS_ATTACHED, vgpu->status))
> + return -EINVAL;
> +
> gfn = pte_ops->get_pfn(ge);
>
> switch (ge->type) {
> --
> 2.41.0.487.g6d72f3e995-goog
>
