From: Christian König <christian.koenig@amd.com>
Date: Wed, 13 Mar 2019 09:11:19 +0000 (+0100)
Subject: drm: fallback to dma_alloc_coherent when memory encryption is active
X-Git-Tag: v5.2-rc1~118^2~29^2~45
X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=64e1f830ea5b3516a4256ed1c504a265d7f2a65c;p=thirdparty%2Fkernel%2Flinux.git

drm: fallback to dma_alloc_coherent when memory encryption is active

We can't just map any randome page we get when memory encryption is
active.

Signed-off-by: Christian König <christian.koenig@amd.com>
Acked-by: Alex Deucher <alexander.deucher@amd.com>
Link: https://patchwork.kernel.org/patch/10850833/
---

diff --git a/drivers/gpu/drm/drm_memory.c b/drivers/gpu/drm/drm_memory.c
index 8dbcdc77f6bfb..132fef8ff1b65 100644
--- a/drivers/gpu/drm/drm_memory.c
+++ b/drivers/gpu/drm/drm_memory.c
@@ -168,6 +168,13 @@ bool drm_need_swiotlb(int dma_bits)
 	if (xen_pv_domain())
 		return true;
 
+	/*
+	 * Enforce dma_alloc_coherent when memory encryption is active as well
+	 * for the same reasons as for Xen paravirtual hosts.
+	 */
+	if (mem_encrypt_active())
+		return true;
+
 	for (tmp = iomem_resource.child; tmp; tmp = tmp->sibling) {
 		max_iomem = max(max_iomem,  tmp->end);
 	}