5.15-stable review patch. If anyone has any objections, please let me know.
------------------
From: Aneesh Kumar K.V (Arm) <aneesh.kumar@kernel.org>
[ Upstream commit af95a0ebc0a0db0762be75f51eadf770bad01aaa ]
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 <jgg@nvidia.com>
Tested-by: Michael Kelley <redacted>
Tested-by: Mostafa Saleh <smostafa@google.com>
Reviewed-by: Petr Tesarik <redacted>
Signed-off-by: Aneesh Kumar K.V (Arm) <aneesh.kumar@kernel.org>
Link: https://lore.kernel.org/r/20260717180442.110954-4-aneesh.kumar@kernel.org (local)
Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
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 aa47d955de6ba..dfef5d7f5885a 100644
--- a/drivers/iommu/dma-iommu.c
+++ b/drivers/iommu/dma-iommu.c
@@ -1208,13 +1208,16 @@ static void *iommu_dma_alloc(struct device *dev, size_t size,
}
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);--
2.53.0