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 sdonthineni@nvidia.com --- 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 7b04f7575796b..ee45dee33d491 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