On 2021-10-21 10:06, Christoph Hellwig wrote:
Instead of blindly running into a blocking operation for a non-blocking gfp, return NULL and spew an error. Note that Kconfig prevents this for all currently relevant platforms, and this is just a debug check.
Reviewed-by: Robin Murphy <robin.mur...@arm.com>
Signed-off-by: Christoph Hellwig <h...@lst.de> --- kernel/dma/direct.c | 9 +++++---- 1 file changed, 5 insertions(+), 4 deletions(-) diff --git a/kernel/dma/direct.c b/kernel/dma/direct.c index d66f37f34ba71..680fe10410645 100644 --- a/kernel/dma/direct.c +++ b/kernel/dma/direct.c @@ -154,6 +154,9 @@ static void *dma_direct_alloc_from_pool(struct device *dev, size_t size, u64 phys_mask; void *ret;+ if (WARN_ON_ONCE(!IS_ENABLED(CONFIG_DMA_COHERENT_POOL)))+ return NULL; + gfp |= dma_direct_optimal_gfp_mask(dev, dev->coherent_dma_mask, &phys_mask); page = dma_alloc_from_pool(dev, size, &ret, gfp, dma_coherent_ok); @@ -234,8 +237,7 @@ void *dma_direct_alloc(struct device *dev, size_t size, * Decrypting memory may block, so allocate the memory from the atomic * pools if we can't block. */ - if (IS_ENABLED(CONFIG_DMA_COHERENT_POOL) && - force_dma_unencrypted(dev) && !gfpflags_allow_blocking(gfp) && + if (force_dma_unencrypted(dev) && !gfpflags_allow_blocking(gfp) && !is_swiotlb_for_alloc(dev)) return dma_direct_alloc_from_pool(dev, size, dma_handle, gfp);@@ -353,8 +355,7 @@ struct page *dma_direct_alloc_pages(struct device *dev, size_t size,struct page *page; void *ret;- if (IS_ENABLED(CONFIG_DMA_COHERENT_POOL) &&- force_dma_unencrypted(dev) && !gfpflags_allow_blocking(gfp) && + if (force_dma_unencrypted(dev) && !gfpflags_allow_blocking(gfp) && !is_swiotlb_for_alloc(dev)) return dma_direct_alloc_from_pool(dev, size, dma_handle, gfp);
_______________________________________________ iommu mailing list iommu@lists.linux-foundation.org https://lists.linuxfoundation.org/mailman/listinfo/iommu
