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 <thomas.lendacky@amd.com>
Signed-off-by: Brijesh Singh <brijesh.singh@amd.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Borislav Petkov <bp@suse.de>C
Tested-by: Borislav Petkov <bp@suse.de>
Cc: kvm@vger.kernel.org
Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Cc: Borislav Petkov <bp@alien8.de>
Link: https://lkml.kernel.org/r/20171020143059.3291-12-brijesh.singh@amd.com
diff --git a/lib/swiotlb.c b/lib/swiotlb.c
index 8c6c83e..cea19aa 100644
--- a/lib/swiotlb.c
+++ b/lib/swiotlb.c
@@ -507,8 +507,9 @@
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);