From d7b417fa08d1187923c270bc33a3555c2fcff8b9 Mon Sep 17 00:00:00 2001 From: Tom Lendacky Date: Fri, 20 Oct 2017 09:30:53 -0500 Subject: x86/mm: Add DMA support for SEV memory encryption DMA access to encrypted memory cannot be performed when SEV is active. In order for DMA to properly work when SEV is active, the SWIOTLB bounce buffers must be used. Signed-off-by: Tom Lendacky Signed-off-by: Brijesh Singh Signed-off-by: Thomas Gleixner Reviewed-by: Borislav Petkov C Tested-by: Borislav Petkov Cc: kvm@vger.kernel.org Cc: Konrad Rzeszutek Wilk Cc: Borislav Petkov Link: https://lkml.kernel.org/r/20171020143059.3291-12-brijesh.singh@amd.com --- lib/swiotlb.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) (limited to 'lib') diff --git a/lib/swiotlb.c b/lib/swiotlb.c index 8c6c83ef57a4..cea19aaf303c 100644 --- a/lib/swiotlb.c +++ b/lib/swiotlb.c @@ -507,8 +507,9 @@ phys_addr_t swiotlb_tbl_map_single(struct device *hwdev, if (no_iotlb_memory) panic("Can not allocate SWIOTLB buffer earlier and can't now provide you with the DMA bounce buffer"); - if (sme_active()) - pr_warn_once("SME is active and system is using DMA bounce buffers\n"); + if (mem_encrypt_active()) + pr_warn_once("%s is active and system is using DMA bounce buffers\n", + sme_active() ? "SME" : "SEV"); mask = dma_get_seg_boundary(hwdev); -- cgit