[mutter] render-device: Unmake the EGLContext after checking whether hw accelerated

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

commit be4e6484ae600e1757fc2d13461ded9777829fbf
Author: Jonas Ådahl <jadahl gmail com>
Date:   Sat Sep 3 18:34:49 2022 +0200

    render-device: Unmake the EGLContext after checking whether hw accelerated
    
    When creating a render device, we create a temporary EGLContext where we
    then query the `GL_RENDERER` string to check whether the renderer is any
    of the known software renderers. After we're done, we destroy the
    context and move on.
    
    This should be fine as according to specification eglDestroyContext(),
    with the context being actually destroyed a bit later when it's no
    longer current, but mesa, when running RK3399 (Pinebook Pro), this
    results in a crash in a future eglMakeCurrent():
    
      #0 in dri_unbind_context () at ../src/gallium/frontends/dri/dri_context.c:266
      #1 in driUnbindContext () at ../src/gallium/frontends/dri/dri_util.c:763
      #2 in dri2_make_current () at ../src/egl/drivers/dri2/egl_dri2.c:1814
      #3 in eglMakeCurrent () at ../src/egl/main/eglapi.c:907
      ...
    
    We can avoid this, however, by calling eglMakeCurrent() with
    EGL_NO_CONTEXT on the EGLDisplay, prior to destroying, effectively
    avoiding the crash, so lets do that.
    
    Related: https://gitlab.freedesktop.org/mesa/mesa/-/issues/7194
    Closes: https://gitlab.gnome.org/GNOME/mutter/-/issues/2414
    Part-of: <https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/2612>

 src/backends/native/meta-render-device.c | 7 ++++++-
 1 file changed, 6 insertions(+), 1 deletion(-)
---
diff --git a/src/backends/native/meta-render-device.c b/src/backends/native/meta-render-device.c
index 982f308149..65e482ad91 100644
--- a/src/backends/native/meta-render-device.c
+++ b/src/backends/native/meta-render-device.c
@@ -114,10 +114,15 @@ detect_hardware_rendering (MetaRenderDevice *render_device)
   if (g_str_has_prefix (renderer_str, "llvmpipe") ||
       g_str_has_prefix (renderer_str, "softpipe") ||
       g_str_has_prefix (renderer_str, "swrast"))
-    goto out_has_context;
+    goto out_current_context;
 
   priv->is_hardware_rendering = TRUE;
 
+out_current_context:
+  meta_egl_make_current (egl, priv->egl_display,
+                         EGL_NO_SURFACE, EGL_NO_SURFACE,
+                         EGL_NO_CONTEXT, NULL);
+
 out_has_context:
   meta_egl_destroy_context (egl, priv->egl_display, egl_context, NULL);
 }