Re: [PATCH v2 29/33] ui/gtk: handle console hotplug/unplug events

[Akihiko Odaki]

On 2026/06/08 16:16, Marc-André Lureau wrote:

Register a console notifier so the GTK display dynamically creates and
destroys VirtualConsole tabs when graphic consoles are added or removed
at runtime (e.g. vfio-pci with display=on hotplug).

Add skips consoles that already have a VC binding, remove skips unknown
consoles.

Signed-off-by: Marc-André Lureau <marcandre.lur...@redhat.com>
---
  include/ui/gtk.h |  1 +
  ui/gtk.c         | 77 +++++++++++++++++++++++++++++++++++++++++++++++++++++++-
  2 files changed, 77 insertions(+), 1 deletion(-)

diff --git a/include/ui/gtk.h b/include/ui/gtk.h
index b0be5070795..6cb611ce474 100644
--- a/include/ui/gtk.h
+++ b/include/ui/gtk.h
@@ -140,6 +140,7 @@ struct GtkDisplayState {

GdkCursor *null_cursor;

      Notifier mouse_mode_notifier;
+    Notifier console_notifier;
      gboolean free_scale;
      gboolean keep_aspect_ratio;

diff --git a/ui/gtk.c b/ui/gtk.c

index 6325704c397..6ef58d1367c 100644
--- a/ui/gtk.c
+++ b/ui/gtk.c
@@ -2332,7 +2332,8 @@ static bool gd_scale_valid(double scale)
      return scale >= VC_SCALE_MIN && scale <= VC_SCALE_MAX;
  }

-static void add_gfx_console(GtkDisplayState *s, QemuConsole *con)

+static VirtualConsole *
+add_gfx_console(GtkDisplayState *s, QemuConsole *con)
  {
      VirtualConsole *vc = g_new0(VirtualConsole, 1);
      const DisplayChangeListenerOps *ops = &dcl_ops;
@@ -2414,6 +2415,76 @@ static void add_gfx_console(GtkDisplayState *s, 
QemuConsole *con)
      qemu_console_register_listener(con, &vc->gfx.dcl, ops);

gd_connect_vc_gfx_signals(vc);

+    return vc;
+}
+
+static void gd_vc_add_gfx(GtkDisplayState *s, QemuConsole *con)
+{
+    VirtualConsole *vc;
+    int i;
+
+    for (i = 0; i < (int)s->vcs->len; i++) {
+        VirtualConsole *v = g_ptr_array_index(s->vcs, i);
+        if (v->type == GD_VC_GFX && v->gfx.dcl.con == con) {
+            return;
+        }
+    }
+
+    vc = add_gfx_console(s, con);
+    gtk_widget_show_all(vc->tab_item);
+    gtk_widget_realize(vc->gfx.drawing_area);
+
+    if (s->free_scale) {
+        gd_update_windowsize(vc);
+    }
+
+    gd_update_caption(s);
+    gd_rebuild_vc_menu(s);
+
+    gtk_notebook_set_show_tabs(GTK_NOTEBOOK(s->notebook), true);

This ignores the user-specified show-tabs configuration.

Regards,
Akihiko Odaki

+}
+
+static void gd_vc_remove_gfx(GtkDisplayState *s, QemuConsole *con)
+{
+    VirtualConsole *vc = NULL;
+    guint idx;
+
+    for (idx = 0; idx < s->vcs->len; idx++) {
+        VirtualConsole *v = g_ptr_array_index(s->vcs, idx);
+        if (v->type == GD_VC_GFX && v->gfx.dcl.con == con) {
+            vc = v;
+            break;
+        }
+    }
+    if (!vc) {
+        return;
+    }
+
+    if (s->kbd_owner == vc) {
+        gd_ungrab_keyboard(s);
+    }
+    if (s->ptr_owner == vc) {
+        gd_ungrab_pointer(s);
+    }
+
+    g_ptr_array_remove_index(s->vcs, idx);
+    gd_rebuild_vc_menu(s);
+    gd_update_caption(s);
+}
+
+static void gd_console_notify(Notifier *n, void *data)
+{
+    GtkDisplayState *s = container_of(n, GtkDisplayState, console_notifier);
+    QemuConsoleEvent *event = data;
+
+    switch (event->type) {
+    case QEMU_CONSOLE_ADDED:
+        gd_vc_add_gfx(s, event->con);
+        break;
+    case QEMU_CONSOLE_REMOVED:
+        gd_vc_remove_gfx(s, event->con);
+        break;
+    }
  }

static void gd_create_menu_view(GtkDisplayState *s, DisplayOptions *opts)

@@ -2688,6 +2759,9 @@ static void gtk_display_init(DisplayState *ds, 
DisplayOptions *opts)

gd_create_menus(s, opts); + s->console_notifier.notify = gd_console_notify;

+    qemu_console_add_notifier(&s->console_notifier);
+
      gd_connect_signals(s);

gtk_notebook_set_show_tabs(GTK_NOTEBOOK(s->notebook), FALSE);

@@ -2808,6 +2882,7 @@ static void gtk_display_cleanup(void)
          return;
      }

+ qemu_console_remove_notifier(&s->console_notifier);

      qemu_remove_mouse_mode_change_notifier(&s->mouse_mode_notifier);
      gd_clipboard_cleanup(s);
      g_signal_handlers_disconnect_by_func(s->notebook,