Get currently bound GL context when creating new GL context and restore
it after the creation for consistency. In particular, if there was no GL
context bound when gd_gl_area_create_context() invoked, then GL context
will be unbound, which is important GL housekeeping detail because GL may
be performed by different QEMU process threads.

Signed-off-by: Dmitry Osipenko <dmitry.osipenko@collabora.com>
---
 ui/gtk-gl-area.c | 10 +++++++++-
 1 file changed, 9 insertions(+), 1 deletion(-)

diff --git a/ui/gtk-gl-area.c b/ui/gtk-gl-area.c
index cd86022d264a..fb783db3042d 100644
--- a/ui/gtk-gl-area.c
+++ b/ui/gtk-gl-area.c
@@ -251,11 +251,13 @@ QEMUGLContext gd_gl_area_create_context(DisplayGLCtx *dgc,
                                         QEMUGLParams *params)
 {
     VirtualConsole *vc = container_of(dgc, VirtualConsole, gfx.dgc);
+    GdkGLContext *ctx, *current_ctx;
     GdkWindow *window;
-    GdkGLContext *ctx;
     GError *err = NULL;
     int major, minor;
 
+    current_ctx = gdk_gl_context_get_current();
+
     window = gtk_widget_get_window(vc->gfx.drawing_area);
     ctx = gdk_window_create_gl_context(window, &err);
     if (err) {
@@ -284,6 +286,12 @@ QEMUGLContext gd_gl_area_create_context(DisplayGLCtx *dgc,
         g_clear_object(&ctx);
     }
 
+    if (current_ctx) {
+        gdk_gl_context_make_current(current_ctx);
+    } else {
+        gdk_gl_context_clear_current();
+    }
+
     trace_gd_gl_area_create_context(ctx, params->major_ver, params->minor_ver);
     return ctx;
 }
-- 
2.52.0