Current implementation of __iommu_dma_alloc_pages() keeps adding __GFP_HIGHMEM to GFP flags regardless of whether other zone flags are already included in the incoming flags. If __GFP_DMA or __GFP_DMA32 is set at the same time as __GFP_HIGHMEM, the allocation fails due to invalid zone flag combination.
Fix this by checking for __GFP_DMA and __GFP_DMA32 in incoming GFP flags and adding __GFP_HIGHMEM only if they are not present. Signed-off-by: Tomasz Figa <tf...@chromium.org> --- drivers/iommu/dma-iommu.c | 10 ++++++++-- 1 file changed, 8 insertions(+), 2 deletions(-) diff --git a/drivers/iommu/dma-iommu.c b/drivers/iommu/dma-iommu.c index 9d1cebe7f6cb..29965a092a69 100644 --- a/drivers/iommu/dma-iommu.c +++ b/drivers/iommu/dma-iommu.c @@ -445,8 +445,14 @@ static struct page **__iommu_dma_alloc_pages(unsigned int count, if (!pages) return NULL; - /* IOMMU can map any pages, so himem can also be used here */ - gfp |= __GFP_NOWARN | __GFP_HIGHMEM; + /* + * IOMMU can map any pages, so himem can also be used here, + * unless another DMA zone is explicitly requested. + */ + if (!(gfp & (__GFP_DMA | __GFP_DMA32))) + gfp |= __GFP_HIGHMEM; + + gfp |= __GFP_NOWARN; while (count) { struct page *page = NULL; -- 2.13.1.611.g7e3b11ae1-goog _______________________________________________ iommu mailing list iommu@lists.linux-foundation.org https://lists.linuxfoundation.org/mailman/listinfo/iommu