From 4f43a6d376dad78646aaffb1c2a3c819c9d6af43 Mon Sep 17 00:00:00 2001 From: Shanker Donthineni Date: Mon, 11 Aug 2025 13:17:59 -0500 Subject: [PATCH] dma/pool: Ensure DMA_DIRECT_REMAP allocations are decrypted commit 89a2d212bdb4bc29bed8e7077abe054b801137ea upstream. When CONFIG_DMA_DIRECT_REMAP is enabled, atomic pool pages are remapped via dma_common_contiguous_remap() using the supplied pgprot. Currently, the mapping uses pgprot_dmacoherent(PAGE_KERNEL), which leaves the memory encrypted on systems with memory encryption enabled (e.g., ARM CCA Realms). This can cause the DMA layer to fail or crash when accessing the memory, as the underlying physical pages are not configured as expected. Fix this by requesting a decrypted mapping in the vmap() call: pgprot_decrypted(pgprot_dmacoherent(PAGE_KERNEL)) This ensures that atomic pool memory is consistently mapped unencrypted. Cc: stable@vger.kernel.org Signed-off-by: Shanker Donthineni Reviewed-by: Catalin Marinas Signed-off-by: Marek Szyprowski Link: https://lore.kernel.org/r/20250811181759.998805-1-sdonthineni@nvidia.com Signed-off-by: Greg Kroah-Hartman --- kernel/dma/pool.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/kernel/dma/pool.c b/kernel/dma/pool.c index b481c48a31a6..6b0be9598a97 100644 --- a/kernel/dma/pool.c +++ b/kernel/dma/pool.c @@ -102,8 +102,8 @@ static int atomic_pool_expand(struct gen_pool *pool, size_t pool_size, #ifdef CONFIG_DMA_DIRECT_REMAP addr = dma_common_contiguous_remap(page, pool_size, - pgprot_dmacoherent(PAGE_KERNEL), - __builtin_return_address(0)); + pgprot_decrypted(pgprot_dmacoherent(PAGE_KERNEL)), + __builtin_return_address(0)); if (!addr) goto free_page; #else