x86/mm: unencrypted non-blocking DMA allocations use coherent pools

When CONFIG_AMD_MEM_ENCRYPT is enabled and a device requires unencrypted
DMA, all non-blocking allocations must originate from the atomic DMA
coherent pools.

Select CONFIG_DMA_COHERENT_POOL for CONFIG_AMD_MEM_ENCRYPT.

Signed-off-by: David Rientjes <rientjes@google.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>

diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig
index 1d6104e..2bf2222 100644 (file)
--- a/arch/x86/Kconfig
+++ b/arch/x86/Kconfig
@@ -1520,6 +1520,7 @@ config X86_CPA_STATISTICS
 config AMD_MEM_ENCRYPT
        bool "AMD Secure Memory Encryption (SME) support"
        depends on X86_64 && CPU_SUP_AMD
+       select DMA_COHERENT_POOL
        select DYNAMIC_PHYSICAL_MASK
        select ARCH_USE_MEMREMAP_PROT
        select ARCH_HAS_FORCE_DMA_UNENCRYPTED