X-Git-Url: https://repo.jachan.dev/J-linux.git/blobdiff_plain/5d766d55d163a60b709317b15db6c8bb02bf54e4..a9a507013a6f98218d1797c8808bd9ba1e79782d:/drivers/gpu/drm/amd/amdgpu/amdgpu_gem.c

diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_gem.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_gem.c
index d0d9bc445d7b..854fc497844b 100644
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_gem.c
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_gem.c
@@ -255,6 +255,15 @@ static int amdgpu_gem_object_mmap(struct drm_gem_object *obj, struct vm_area_str
 	if (bo->flags & AMDGPU_GEM_CREATE_NO_CPU_ACCESS)
 		return -EPERM;
 
+	/* Workaround for Thunk bug creating PROT_NONE,MAP_PRIVATE mappings
+	 * for debugger access to invisible VRAM. Should have used MAP_SHARED
+	 * instead. Clearing VM_MAYWRITE prevents the mapping from ever
+	 * becoming writable and makes is_cow_mapping(vm_flags) false.
+	 */
+	if (is_cow_mapping(vma->vm_flags) &&
+	    !(vma->vm_flags & (VM_READ | VM_WRITE | VM_EXEC)))
+		vma->vm_flags &= ~VM_MAYWRITE;
+
 	return drm_gem_ttm_mmap(obj, vma);
 }