[mutter] wayland/dma-buf: Only try to query KMS device on native backend

[Marge Bot <marge-bot src gnome org>]

commit a07fd4ee6628956c86d4bb50d52254997b4b528b
Author: Jonas Ådahl <jadahl gmail com>
Date:   Thu Aug 4 08:09:23 2022 +0200

    wayland/dma-buf: Only try to query KMS device on native backend
    
    This fixes a crash when using the nested backend and DMA buf Wayland
    clients.
    
    Part-of: <https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/2553>

 src/wayland/meta-wayland-dma-buf.c | 7 +++++--
 1 file changed, 5 insertions(+), 2 deletions(-)
---
diff --git a/src/wayland/meta-wayland-dma-buf.c b/src/wayland/meta-wayland-dma-buf.c
index 67ebbec84e..289e255524 100644
--- a/src/wayland/meta-wayland-dma-buf.c
+++ b/src/wayland/meta-wayland-dma-buf.c
@@ -152,12 +152,15 @@ static GQuark quark_dma_buf_surface_feedback;
 static gboolean
 should_send_modifiers (MetaBackend *backend)
 {
-  MetaRenderer *renderer = meta_backend_get_renderer (backend);
-  MetaRendererNative *renderer_native = META_RENDERER_NATIVE (renderer);
+  MetaRendererNative *renderer_native;
   MetaGpuKms *gpu_kms;
   MetaKmsDevice *kms_device;
   MetaKmsDeviceFlag flags;
 
+  if (!META_IS_BACKEND_NATIVE (backend))
+    return FALSE;
+
+  renderer_native = META_RENDERER_NATIVE (meta_backend_get_renderer (backend));
   gpu_kms = meta_renderer_native_get_primary_gpu (renderer_native);
   kms_device = meta_gpu_kms_get_kms_device (gpu_kms);