On Fri, Jul 22, 2022 at 06:18:00PM -0600, Alex Williamson wrote: > External email: Use caution opening links or attachments > > > On Fri, 22 Jul 2022 16:12:19 -0700 > Nicolin Chen <nicolinc@xxxxxxxxxx> wrote: > > > On Fri, Jul 22, 2022 at 04:11:29PM -0600, Alex Williamson wrote: > > > > > GVT-g explodes for me with this series on my Broadwell test system, > > > continuously spewing the following: > > > > Thank you for running additional tests. > > > > > [ 47.348778] WARNING: CPU: 3 PID: 501 at drivers/vfio/vfio_iommu_type1.c:978 vfio_iommu_type1_unpin_pages+0x7b/0x100 [vfio_iommu_type1] > > > > > Line 978 is the WARN_ON(i != npage) line. For the cases where we don't > > > find a matching vfio_dma, I'm seeing addresses that look maybe like > > > we're shifting a value that's already an iova by PAGE_SHIFT somewhere. > > > > Hmm..I don't understand the PAGE_SHIFT part. Do you mind clarifying? > > The iova was a very large address for a 4GB VM with a lot of zeros on > the low order bits, ex. 0x162459000000. Thanks, Ah! Thanks for the hint. The following commit did a double shifting: "vfio: Pass in starting IOVA to vfio_pin/unpin_pages AP" And the following change should fix: ------------------- diff --git a/drivers/gpu/drm/i915/gvt/kvmgt.c b/drivers/gpu/drm/i915/gvt/kvmgt.c index 481dd2aeb40e..4790c7f35b88 100644 --- a/drivers/gpu/drm/i915/gvt/kvmgt.c +++ b/drivers/gpu/drm/i915/gvt/kvmgt.c @@ -293,7 +293,7 @@ static int gvt_dma_map_page(struct intel_vgpu *vgpu, unsigned long gfn, if (dma_mapping_error(dev, *dma_addr)) { gvt_vgpu_err("DMA mapping failed for pfn 0x%lx, ret %d\n", page_to_pfn(page), ret); - gvt_unpin_guest_page(vgpu, gfn << PAGE_SHIFT, size); + gvt_unpin_guest_page(vgpu, gfn, size); return -ENOMEM; } @@ -306,7 +306,7 @@ static void gvt_dma_unmap_page(struct intel_vgpu *vgpu, unsigned long gfn, struct device *dev = vgpu->gvt->gt->i915->drm.dev; dma_unmap_page(dev, dma_addr, size, DMA_BIDIRECTIONAL); - gvt_unpin_guest_page(vgpu, gfn << PAGE_SHIFT, size); + gvt_unpin_guest_page(vgpu, gfn, size); } static struct gvt_dma *__gvt_cache_find_dma_addr(struct intel_vgpu *vgpu, ------------------- So, I think that I should send a v4, given that the patches aren't officially applied?