drm/amdgpu: Fail fb creation from imported dma-bufs. (v2)

Any use of the framebuffer will migrate it to VRAM, which is not sensible for
an imported dma-buf.

v2: Use DRM_DEBUG_KMS to prevent userspace accidentally spamming dmesg.

Reviewed-by: Michel Dänzer <michel.daenzer@amd.com>
Reviewed-by: Christian König <christian.koenig@amd.com>
Signed-off-by: Christopher James Halse Rogers <christopher.halse.rogers@canonical.com>
CC: amd-gfx@lists.freedesktop.org
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_display.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_display.c
index ce15721..96926a2 100644 (file)
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_display.c
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_display.c
@@ -614,6 +614,12 @@ amdgpu_user_framebuffer_create(struct drm_device *dev,
                return ERR_PTR(-ENOENT);
        }
 
+       /* Handle is imported dma-buf, so cannot be migrated to VRAM for scanout */
+       if (obj->import_attach) {
+               DRM_DEBUG_KMS("Cannot create framebuffer from imported dma_buf\n");
+               return ERR_PTR(-EINVAL);
+       }
+
        amdgpu_fb = kzalloc(sizeof(*amdgpu_fb), GFP_KERNEL);
        if (amdgpu_fb == NULL) {
                drm_gem_object_unreference_unlocked(obj);