Re: [PATCH v6 14/20] dma-direct: return struct page from dma_direct_alloc_from_pool()
From: Jason Gunthorpe <jgg@ziepe.ca>
Date: 2026-06-09 14:15:43
Also in:
linux-arm-kernel, linux-coco, linux-iommu, linux-s390, lkml, stable
On Thu, Jun 04, 2026 at 02:09:53PM +0530, Aneesh Kumar K.V (Arm) wrote:
quoted hunk ↗ jump to hunk
@@ -270,9 +270,12 @@ void *dma_direct_alloc(struct device *dev, size_t size, * the atomic pools instead if we aren't allowed block. */ if ((remap || (attrs & DMA_ATTR_CC_SHARED)) && - dma_direct_use_pool(dev, gfp)) - return dma_direct_alloc_from_pool(dev, size, dma_handle, - gfp, attrs); + dma_direct_use_pool(dev, gfp)) { + page = dma_direct_alloc_from_pool(dev, size, + dma_handle, &cpu_addr, + gfp, attrs); + return page ? cpu_addr : NULL; + }
You should probably put this at the start of the series so it can be backported Reviewed-by: Jason Gunthorpe <jgg@nvidia.com> To Petr's question I think this just shows nobody is really stressing the PCI dma paths on CC VMs today. if (force_dma_unencrypted(dev) && dma_direct_use_pool(dev, gfp)) return dma_direct_alloc_from_pool(dev, size, dma_handle, gfp); For instance the places even calling dma_alloc_pages() don't look like things people would use in a CC VM. Jason