diff --git a/src/amd/vulkan/radv_device.c b/src/amd/vulkan/radv_device.c
index b164bbca5ae..8b0a106e54b 100644
--- a/src/amd/vulkan/radv_device.c
+++ b/src/amd/vulkan/radv_device.c
@@ -557,7 +557,12 @@ radv_physical_device_get_supported_extensions(const struct radv_physical_device
       .NV_compute_shader_derivatives = true,
       .NV_mesh_shader = device->use_ngg && device->rad_info.chip_class >= GFX10_3 &&
                         device->instance->perftest_flags & RADV_PERFTEST_NV_MS && !device->use_llvm,
-      .VALVE_descriptor_set_host_mapping = true,
+      /* Undocumented extension purely for vkd3d-proton. This check is to prevent anyone else from
+       * using it.
+       */
+      .VALVE_descriptor_set_host_mapping =
+         device->vk.instance->app_info.engine_name &&
+         strcmp(device->vk.instance->app_info.engine_name, "vkd3d") == 0,
       .VALVE_mutable_descriptor_type = true,
    };
 }