From af95a0ebc0a0db0762be75f51eadf770bad01aaa Mon Sep 17 00:00:00 2001 From: "Aneesh Kumar K.V (Arm)" Date: Fri, 17 Jul 2026 23:34:21 +0530 Subject: [PATCH] iommu/dma: Check atomic pool allocation result directly The non-blocking, non-coherent allocation path uses dma_alloc_from_pool(), which returns the allocated page and fills cpu_addr only on success. Do not rely on cpu_addr to detect allocation failure in this path. Check the returned page directly before using it for the IOMMU mapping. Fixes: 9420139f516d ("dma-pool: fix coherent pool allocations for IOMMU mappings") Reviewed-by: Jason Gunthorpe Tested-by: Michael Kelley Tested-by: Mostafa Saleh Reviewed-by: Petr Tesarik Signed-off-by: Aneesh Kumar K.V (Arm) Link: https://lore.kernel.org/r/20260717180442.110954-4-aneesh.kumar@kernel.org Signed-off-by: Marek Szyprowski --- drivers/iommu/dma-iommu.c | 13 ++++++++----- 1 file changed, 8 insertions(+), 5 deletions(-) diff --git a/drivers/iommu/dma-iommu.c b/drivers/iommu/dma-iommu.c index 9abaec0703ef..68c686c1e81a 100644 --- a/drivers/iommu/dma-iommu.c +++ b/drivers/iommu/dma-iommu.c @@ -1671,13 +1671,16 @@ void *iommu_dma_alloc(struct device *dev, size_t size, dma_addr_t *handle, } if (IS_ENABLED(CONFIG_DMA_DIRECT_REMAP) && - !gfpflags_allow_blocking(gfp) && !coherent) + !gfpflags_allow_blocking(gfp) && !coherent) { page = dma_alloc_from_pool(dev, PAGE_ALIGN(size), &cpu_addr, - gfp, NULL); - else + gfp, NULL); + if (!page) + return NULL; + } else { cpu_addr = iommu_dma_alloc_pages(dev, size, &page, gfp, attrs); - if (!cpu_addr) - return NULL; + if (!cpu_addr) + return NULL; + } *handle = __iommu_dma_map(dev, page_to_phys(page), size, ioprot, dev->coherent_dma_mask);