Re: "dma-mapping: remove CONFIG_DMA_REMAP" causes AMD SME boot fail

Christoph Hellwig
2022-03-30T18:01:33Z

Can you try this patch, which is a bit of a hack?

diff --git a/arch/x86/mm/mem_encrypt.c b/arch/x86/mm/mem_encrypt.c
index 50d209939c66c..61997c2ee0a17 100644
--- a/arch/x86/mm/mem_encrypt.c
+++ b/arch/x86/mm/mem_encrypt.c
@@ -28,7 +28,8 @@ bool force_dma_unencrypted(struct device *dev)
* device does not support DMA to addresses that include the
* encryption mask.
*/
- if (cc_platform_has(CC_ATTR_HOST_MEM_ENCRYPT)) {
+ if (cc_platform_has(CC_ATTR_HOST_MEM_ENCRYPT) &&
+ !get_dma_ops(dev)) {
u64 dma_enc_mask = DMA_BIT_MASK(__ffs64(sme_me_mask));
u64 dma_dev_mask = min_not_zero(dev->coherent_dma_mask,
dev->bus_dma_limit);