Upgrade !1441 to commit 163776ae

4 files changed, 1354 insertions, 325 deletions

diff --git a/.SRCINFO b/.SRCINFO
index 63914ebc5be1..29dbfb8e4604 100644
--- a/.SRCINFO
+++ b/.SRCINFO
@@ -31,11 +31,9 @@ pkgbase = mutter-dynamic-buffering
 	depends = libxkbfile
 	depends = libsysprof-capture
 	source = mutter-dynamic-buffering::git+https://gitlab.gnome.org/GNOME/mutter.git#commit=9249aba72a5c4454894c08735a4963ca1665e34d
-	source = backports.patch
 	source = mr1441.patch
 	sha256sums = SKIP
-	sha256sums = 4bfebf11fd10d2829977cb3c77491bcb9eaa7779f9fc72cdbf10cb0f56adc813
-	sha256sums = cf99896763558258f489ff0e9a1e8001f716d63b06366f740e044cc72a71d3e7
+	sha256sums = fc1963c134b4548950241d175a7389ec5f1a0b6a86cefb6d0918d958d66252a2
 
 pkgname = mutter-dynamic-buffering
 	groups = gnome
diff --git a/PKGBUILD b/PKGBUILD
index c0039104b741..fb4395bbc0e6 100644
--- a/PKGBUILD
+++ b/PKGBUILD
@@ -21,12 +21,10 @@ makedepends=(gobject-introspection git egl-wayland meson xorg-server
 #options=(debug)
 _commit=9249aba72a5c4454894c08735a4963ca1665e34d  # tags/42.0^0
 source=("$pkgname::git+https://gitlab.gnome.org/GNOME/mutter.git#commit=$_commit"
-        'backports.patch'
         'mr1441.patch')
 
 sha256sums=('SKIP'
-            '4bfebf11fd10d2829977cb3c77491bcb9eaa7779f9fc72cdbf10cb0f56adc813'
-            'cf99896763558258f489ff0e9a1e8001f716d63b06366f740e044cc72a71d3e7')
+            'fc1963c134b4548950241d175a7389ec5f1a0b6a86cefb6d0918d958d66252a2')
 
 pkgver() {
   cd $pkgname
@@ -36,7 +34,6 @@ pkgver() {
 prepare() {
   cd "$srcdir/$pkgname"
   patch -p1 < "$srcdir/mr1441.patch"
-  patch -p1 < "$srcdir/backports.patch"
 }
 
 build() {
diff --git a/backports.patch b/backports.patch
deleted file mode 100644
index 5852ba662557..000000000000
--- a/backports.patch
+++ /dev/null
@@ -1,79 +0,0 @@
-Author: Daniel van Vugt <daniel.van.vugt@canonical.com>
-Editor: Joakim Soderlund <joakim.soderlund@gmail.com>
-Source: https://gitlab.gnome.org/JockeTF/mutter/-/tree/41.1-2
-Commit: 3b3978c60e6c67e5fe5262d528d5330bc12181d0
-Rebase: Sat Nov 20 09:14:06 2021 +0100
-
-diff --git a/src/backends/native/meta-onscreen-native.c b/src/backends/native/meta-onscreen-native.c
-index eb1e7412a..eacfd2cc1 100644
---- a/src/backends/native/meta-onscreen-native.c
-+++ b/src/backends/native/meta-onscreen-native.c
-@@ -404,7 +406,7 @@ meta_onscreen_native_flip_crtc (CoglOnscreen                *onscreen,
-   kms = meta_kms_device_get_kms (kms_device);
-   kms_update = meta_kms_ensure_pending_update (kms, kms_device);
- 
--  g_assert (meta_gpu_kms_is_crtc_active (gpu_kms, crtc));
-+  g_return_if_fail (meta_gpu_kms_is_crtc_active (gpu_kms, crtc));
- 
-   renderer_gpu_data = meta_renderer_native_get_gpu_data (renderer_native,
-                                                          render_gpu);
-@@ -1011,7 +1013,6 @@ meta_onscreen_native_swap_buffers_with_damage (CoglOnscreen  *onscreen,
-   switch (renderer_gpu_data->mode)
-     {
-     case META_RENDERER_NATIVE_MODE_GBM:
--      g_warn_if_fail (onscreen_native->gbm.next_fb == NULL);
-       g_clear_object (&onscreen_native->gbm.next_fb);
- 
-       use_modifiers = meta_renderer_native_use_modifiers (renderer_native);
-@@ -2068,10 +2069,10 @@ meta_onscreen_native_new (MetaRendererNative *renderer_native,
-                                   "height", height,
-                                   NULL);
- 
--  onscreen_native->renderer_native = renderer_native;
--  onscreen_native->render_gpu = render_gpu;
--  onscreen_native->output = output;
--  onscreen_native->crtc = crtc;
-+  onscreen_native->renderer_native = g_object_ref (renderer_native);
-+  onscreen_native->render_gpu = g_object_ref (render_gpu);
-+  onscreen_native->output = g_object_ref (output);
-+  onscreen_native->crtc = g_object_ref (crtc);
- 
-   return onscreen_native;
- }
-@@ -2126,6 +2127,11 @@ meta_onscreen_native_dispose (GObject *object)
-                    secondary_gpu_state_free);
-   g_clear_pointer (&onscreen_native->next_post.rectangles, g_free);
-   onscreen_native->next_post.n_rectangles = 0;
-+
-+  g_clear_object (&onscreen_native->crtc);
-+  g_clear_object (&onscreen_native->output);
-+  g_clear_object (&onscreen_native->render_gpu);
-+  g_clear_object (&onscreen_native->renderer_native);
- }
- 
- static void
-diff --git a/src/backends/native/meta-renderer-native.c b/src/backends/native/meta-renderer-native.c
-index eb6771b80..f39b0e004 100644
---- a/src/backends/native/meta-renderer-native.c
-+++ b/src/backends/native/meta-renderer-native.c
-@@ -593,12 +593,18 @@ static gboolean
- dummy_power_save_page_flip_cb (gpointer user_data)
- {
-   MetaRendererNative *renderer_native = user_data;
-+  GList *old_list =
-+    g_steal_pointer (&renderer_native->power_save_page_flip_onscreens);
- 
--  g_list_foreach (renderer_native->power_save_page_flip_onscreens,
-+  g_list_foreach (old_list,
-                   (GFunc) meta_onscreen_native_dummy_power_save_page_flip,
-                   NULL);
--  g_clear_list (&renderer_native->power_save_page_flip_onscreens,
-+  g_clear_list (&old_list,
-                 g_object_unref);
-+
-+  if (renderer_native->power_save_page_flip_onscreens != NULL)
-+    return G_SOURCE_CONTINUE;
-+
-   renderer_native->power_save_page_flip_source_id = 0;
- 
-   return G_SOURCE_REMOVE;
diff --git a/mr1441.patch b/mr1441.patch
index 90806337a369..f66842be8b48 100644
--- a/mr1441.patch
+++ b/mr1441.patch
@@ -1,13 +1,22 @@
 Author: Daniel van Vugt <daniel.van.vugt@canonical.com>
 Source: https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/1441
-Commit: 5bb8301fad0f10e5cb2f9058c2edd0e3e1a2fee6
-Rebase: Fri Sep 24 22:03:14 2021 +0800
+Commit: 163776ae49fa9af98405d8225be6e23473d550dc
+Rebase: Fri Mar 11 14:09:17 2022 +0800
 
 diff --git a/clutter/clutter/clutter-frame-clock.c b/clutter/clutter/clutter-frame-clock.c
-index 16098b70f..27bbfd323 100644
+index 6fa2b2588..7a6444ec4 100644
 --- a/clutter/clutter/clutter-frame-clock.c
 +++ b/clutter/clutter/clutter-frame-clock.c
-@@ -68,8 +68,9 @@ typedef enum _ClutterFrameClockState
+@@ -45,6 +45,8 @@ typedef struct _EstimateQueue
+   int next_index;
+ } EstimateQueue;
+ 
++static gboolean triple_buffering_disabled = FALSE;
++
+ #define SYNC_DELAY_FALLBACK_FRACTION 0.875
+ 
+ typedef struct _ClutterFrameListener
+@@ -65,8 +67,9 @@ typedef enum _ClutterFrameClockState
    CLUTTER_FRAME_CLOCK_STATE_INIT,
    CLUTTER_FRAME_CLOCK_STATE_IDLE,
    CLUTTER_FRAME_CLOCK_STATE_SCHEDULED,
@@ -19,7 +28,7 @@ index 16098b70f..27bbfd323 100644
  } ClutterFrameClockState;
  
  struct _ClutterFrameClock
-@@ -99,6 +100,8 @@ struct _ClutterFrameClock
+@@ -96,6 +99,8 @@ struct _ClutterFrameClock
    /* Last KMS buffer submission time. */
    int64_t last_flip_time_us;
  
@@ -28,31 +37,60 @@ index 16098b70f..27bbfd323 100644
    /* Last few durations between dispatch start and buffer swap. */
    EstimateQueue dispatch_to_swap_us;
    /* Last few durations between buffer swap and GPU rendering finish. */
-@@ -278,9 +281,21 @@ clutter_frame_clock_notify_presented (ClutterFrameClock *frame_clock,
+@@ -228,6 +233,10 @@ void
+ clutter_frame_clock_notify_presented (ClutterFrameClock *frame_clock,
+                                       ClutterFrameInfo  *frame_info)
+ {
++  const char *debug_state =
++    frame_clock->state == CLUTTER_FRAME_CLOCK_STATE_DISPATCHED_TWO ?
++    "Triple buffering" : "Double buffering";
++
+   COGL_TRACE_BEGIN_SCOPED (ClutterFrameClockNotifyPresented,
+                            "Frame Clock (presented)");
+ 
+@@ -289,7 +298,8 @@ clutter_frame_clock_notify_presented (ClutterFrameClock *frame_clock,
+         frame_info->cpu_time_before_buffer_swap_us;
+ 
+       CLUTTER_NOTE (FRAME_TIMINGS,
+-                    "dispatch2swap %ld µs, swap2render %ld µs, swap2flip %ld µs",
++                    "%s: dispatch2swap %ld µs, swap2render %ld µs, swap2flip %ld µs",
++                    debug_state,
+                     dispatch_to_swap_us,
+                     swap_to_rendering_done_us,
+                     swap_to_flip_us);
+@@ -303,6 +313,10 @@ clutter_frame_clock_notify_presented (ClutterFrameClock *frame_clock,
+ 
+       frame_clock->got_measurements_last_frame = TRUE;
+     }
++  else
++    {
++      CLUTTER_NOTE (FRAME_TIMINGS, "%s", debug_state);
++    }
+ 
+   if (frame_info->refresh_rate > 1)
+     {
+@@ -317,11 +331,18 @@ clutter_frame_clock_notify_presented (ClutterFrameClock *frame_clock,
      case CLUTTER_FRAME_CLOCK_STATE_SCHEDULED:
        g_warn_if_reached ();
        break;
 -    case CLUTTER_FRAME_CLOCK_STATE_DISPATCHING:
 -    case CLUTTER_FRAME_CLOCK_STATE_PENDING_PRESENTED:
 +    case CLUTTER_FRAME_CLOCK_STATE_DISPATCHED_ONE:
-+      frame_clock->state = CLUTTER_FRAME_CLOCK_STATE_IDLE;
-+      maybe_reschedule_update (frame_clock);
-+      break;
-+    case CLUTTER_FRAME_CLOCK_STATE_DISPATCHED_ONE_AND_SCHEDULED:
-+      /* The GPU has caught up now so we can start using
-+       * last_presentation_time_us again. But rather than dropping back to
-+       * SCHEDULED, let's force a reschedule from IDLE. This way we'll get a
-+       * more precise next update time based on last_presentation_time_us.
-+       */
        frame_clock->state = CLUTTER_FRAME_CLOCK_STATE_IDLE;
-+      clutter_frame_clock_schedule_update (frame_clock);
+       maybe_reschedule_update (frame_clock);
+       break;
++    case CLUTTER_FRAME_CLOCK_STATE_DISPATCHED_ONE_AND_SCHEDULED:
++      frame_clock->state = CLUTTER_FRAME_CLOCK_STATE_SCHEDULED;
++      maybe_reschedule_update (frame_clock);
 +      break;
 +    case CLUTTER_FRAME_CLOCK_STATE_DISPATCHED_TWO:
 +      frame_clock->state = CLUTTER_FRAME_CLOCK_STATE_DISPATCHED_ONE;
-       maybe_reschedule_update (frame_clock);
-       break;
++      maybe_reschedule_update (frame_clock);
++      break;
      }
-@@ -296,11 +311,18 @@ clutter_frame_clock_notify_ready (ClutterFrameClock *frame_clock)
+ }
+ 
+@@ -337,11 +358,18 @@ clutter_frame_clock_notify_ready (ClutterFrameClock *frame_clock)
      case CLUTTER_FRAME_CLOCK_STATE_SCHEDULED:
        g_warn_if_reached ();
        break;
@@ -73,17 +111,52 @@ index 16098b70f..27bbfd323 100644
      }
  }
  
-@@ -375,7 +397,8 @@ calculate_next_update_time_us (ClutterFrameClock *frame_clock,
+@@ -353,6 +381,7 @@ clutter_frame_clock_compute_max_render_time_us (ClutterFrameClock *frame_clock)
+   int64_t max_swap_to_rendering_done_us = 0;
+   int64_t max_swap_to_flip_us = 0;
+   int64_t max_render_time_us;
++  int buffer_queue_latency_frames = 0;
+   int i;
  
    refresh_interval_us = frame_clock->refresh_interval_us;
+@@ -375,6 +404,27 @@ clutter_frame_clock_compute_max_render_time_us (ClutterFrameClock *frame_clock)
+              frame_clock->swap_to_flip_us.values[i]);
+     }
  
--  if (frame_clock->last_presentation_time_us == 0)
-+  if (frame_clock->last_presentation_time_us == 0 ||
-+      frame_clock->state >= CLUTTER_FRAME_CLOCK_STATE_DISPATCHED_ONE)
-     {
-       *out_next_update_time_us =
-         frame_clock->last_dispatch_time_us ?
-@@ -518,8 +541,12 @@ clutter_frame_clock_inhibit (ClutterFrameClock *frame_clock)
++  switch (frame_clock->state)
++    {
++    case CLUTTER_FRAME_CLOCK_STATE_INIT:
++    case CLUTTER_FRAME_CLOCK_STATE_IDLE:
++    case CLUTTER_FRAME_CLOCK_STATE_SCHEDULED:
++      buffer_queue_latency_frames = 0;
++      break;
++    case CLUTTER_FRAME_CLOCK_STATE_DISPATCHED_ONE:
++    case CLUTTER_FRAME_CLOCK_STATE_DISPATCHED_ONE_AND_SCHEDULED:
++      buffer_queue_latency_frames = 1;
++      break;
++    case CLUTTER_FRAME_CLOCK_STATE_DISPATCHED_TWO:
++      g_warn_if_reached ();
++      buffer_queue_latency_frames = 2;
++      break;
++    }
++
++  max_swap_to_flip_us -= refresh_interval_us * buffer_queue_latency_frames;
++  if (max_swap_to_flip_us < 0)
++    max_swap_to_flip_us = 0;
++
+   /* Max render time shows how early the frame clock needs to be dispatched
+    * to make it to the predicted next presentation time. It is composed of:
+    * - An estimate of duration from dispatch start to buffer swap.
+@@ -391,8 +441,6 @@ clutter_frame_clock_compute_max_render_time_us (ClutterFrameClock *frame_clock)
+     frame_clock->vblank_duration_us +
+     clutter_max_render_time_constant_us;
+ 
+-  max_render_time_us = CLAMP (max_render_time_us, 0, refresh_interval_us);
+-
+   return max_render_time_us;
+ }
+ 
+@@ -558,8 +606,12 @@ clutter_frame_clock_inhibit (ClutterFrameClock *frame_clock)
            frame_clock->pending_reschedule = TRUE;
            frame_clock->state = CLUTTER_FRAME_CLOCK_STATE_IDLE;
            break;
@@ -98,7 +171,7 @@ index 16098b70f..27bbfd323 100644
            break;
          }
  
-@@ -555,11 +582,17 @@ clutter_frame_clock_schedule_update_now (ClutterFrameClock *frame_clock)
+@@ -595,11 +647,17 @@ clutter_frame_clock_schedule_update_now (ClutterFrameClock *frame_clock)
      case CLUTTER_FRAME_CLOCK_STATE_INIT:
      case CLUTTER_FRAME_CLOCK_STATE_IDLE:
        next_update_time_us = g_get_monotonic_time ();
@@ -118,7 +191,7 @@ index 16098b70f..27bbfd323 100644
        frame_clock->pending_reschedule = TRUE;
        frame_clock->pending_reschedule_now = TRUE;
        return;
-@@ -568,7 +601,6 @@ clutter_frame_clock_schedule_update_now (ClutterFrameClock *frame_clock)
+@@ -608,7 +666,6 @@ clutter_frame_clock_schedule_update_now (ClutterFrameClock *frame_clock)
    g_warn_if_fail (next_update_time_us != -1);
  
    g_source_set_ready_time (frame_clock->source, next_update_time_us);
@@ -126,7 +199,7 @@ index 16098b70f..27bbfd323 100644
    frame_clock->is_next_presentation_time_valid = FALSE;
  }
  
-@@ -587,6 +619,7 @@ clutter_frame_clock_schedule_update (ClutterFrameClock *frame_clock)
+@@ -627,6 +684,7 @@ clutter_frame_clock_schedule_update (ClutterFrameClock *frame_clock)
      {
      case CLUTTER_FRAME_CLOCK_STATE_INIT:
        next_update_time_us = g_get_monotonic_time ();
@@ -134,7 +207,7 @@ index 16098b70f..27bbfd323 100644
        break;
      case CLUTTER_FRAME_CLOCK_STATE_IDLE:
        calculate_next_update_time_us (frame_clock,
-@@ -594,11 +627,27 @@ clutter_frame_clock_schedule_update (ClutterFrameClock *frame_clock)
+@@ -634,11 +692,28 @@ clutter_frame_clock_schedule_update (ClutterFrameClock *frame_clock)
                                       &frame_clock->next_presentation_time_us);
        frame_clock->is_next_presentation_time_valid =
          (frame_clock->next_presentation_time_us != 0);
@@ -146,7 +219,8 @@ index 16098b70f..27bbfd323 100644
 -    case CLUTTER_FRAME_CLOCK_STATE_DISPATCHING:
 -    case CLUTTER_FRAME_CLOCK_STATE_PENDING_PRESENTED:
 +    case CLUTTER_FRAME_CLOCK_STATE_DISPATCHED_ONE:
-+      if (frame_clock->last_flip_hints & CLUTTER_FRAME_HINT_DIRECT_SCANOUT_ATTEMPTED)
++      if (frame_clock->last_flip_hints & CLUTTER_FRAME_HINT_DIRECT_SCANOUT_ATTEMPTED ||
++          triple_buffering_disabled)
 +        {
 +          /* Force double buffering, disable triple buffering */
 +          frame_clock->pending_reschedule = TRUE;
@@ -164,7 +238,7 @@ index 16098b70f..27bbfd323 100644
        frame_clock->pending_reschedule = TRUE;
        return;
      }
-@@ -606,7 +655,6 @@ clutter_frame_clock_schedule_update (ClutterFrameClock *frame_clock)
+@@ -646,7 +721,6 @@ clutter_frame_clock_schedule_update (ClutterFrameClock *frame_clock)
    g_warn_if_fail (next_update_time_us != -1);
  
    g_source_set_ready_time (frame_clock->source, next_update_time_us);
@@ -172,7 +246,7 @@ index 16098b70f..27bbfd323 100644
  }
  
  static void
-@@ -624,7 +672,7 @@ clutter_frame_clock_dispatch (ClutterFrameClock *frame_clock,
+@@ -670,7 +744,7 @@ clutter_frame_clock_dispatch (ClutterFrameClock *frame_clock,
                             frame_clock->refresh_interval_us;
  
    lateness_us = time_us - ideal_dispatch_time_us;
@@ -181,7 +255,7 @@ index 16098b70f..27bbfd323 100644
      frame_clock->last_dispatch_lateness_us = 0;
    else
      frame_clock->last_dispatch_lateness_us = lateness_us;
-@@ -632,7 +680,21 @@ clutter_frame_clock_dispatch (ClutterFrameClock *frame_clock,
+@@ -678,7 +752,21 @@ clutter_frame_clock_dispatch (ClutterFrameClock *frame_clock,
    frame_clock->last_dispatch_time_us = time_us;
    g_source_set_ready_time (frame_clock->source, -1);
  
@@ -204,7 +278,7 @@ index 16098b70f..27bbfd323 100644
  
    frame_count = frame_clock->frame_count++;
  
-@@ -656,25 +718,31 @@ clutter_frame_clock_dispatch (ClutterFrameClock *frame_clock,
+@@ -703,25 +791,31 @@ clutter_frame_clock_dispatch (ClutterFrameClock *frame_clock,
                                                 frame_clock->listener.user_data);
    COGL_TRACE_END (ClutterFrameClockFrame);
  
@@ -214,11 +288,11 @@ index 16098b70f..27bbfd323 100644
 -    case CLUTTER_FRAME_CLOCK_STATE_INIT:
 -    case CLUTTER_FRAME_CLOCK_STATE_PENDING_PRESENTED:
 -      g_warn_if_reached ();
--      break;
--    case CLUTTER_FRAME_CLOCK_STATE_IDLE:
--    case CLUTTER_FRAME_CLOCK_STATE_SCHEDULED:
 +    case CLUTTER_FRAME_RESULT_PENDING_PRESENTED:
        break;
+-    case CLUTTER_FRAME_CLOCK_STATE_IDLE:
+-    case CLUTTER_FRAME_CLOCK_STATE_SCHEDULED:
+-      break;
 -    case CLUTTER_FRAME_CLOCK_STATE_DISPATCHING:
 -      switch (result)
 +    case CLUTTER_FRAME_RESULT_IDLE:
@@ -248,7 +322,7 @@ index 16098b70f..27bbfd323 100644
          }
        break;
      }
-@@ -696,10 +764,12 @@ frame_clock_source_dispatch (GSource     *source,
+@@ -754,10 +848,12 @@ frame_clock_source_dispatch (GSource     *source,
  }
  
  void
@@ -263,8 +337,18 @@ index 16098b70f..27bbfd323 100644
  }
  
  GString *
+@@ -888,6 +984,9 @@ clutter_frame_clock_class_init (ClutterFrameClockClass *klass)
+ {
+   GObjectClass *object_class = G_OBJECT_CLASS (klass);
+ 
++  if (!g_strcmp0 (g_getenv ("MUTTER_DEBUG_DISABLE_TRIPLE_BUFFERING"), "1"))
++    triple_buffering_disabled = TRUE;
++
+   object_class->dispose = clutter_frame_clock_dispose;
+ 
+   signals[DESTROY] =
 diff --git a/clutter/clutter/clutter-frame-clock.h b/clutter/clutter/clutter-frame-clock.h
-index e71b54987..a37024e2d 100644
+index 91e6b3a13..d750404d5 100644
 --- a/clutter/clutter/clutter-frame-clock.h
 +++ b/clutter/clutter/clutter-frame-clock.h
 @@ -34,6 +34,12 @@ typedef enum _ClutterFrameResult
@@ -280,7 +364,7 @@ index e71b54987..a37024e2d 100644
  #define CLUTTER_TYPE_FRAME_CLOCK (clutter_frame_clock_get_type ())
  CLUTTER_EXPORT
  G_DECLARE_FINAL_TYPE (ClutterFrameClock, clutter_frame_clock,
-@@ -91,8 +97,9 @@ void clutter_frame_clock_remove_timeline (ClutterFrameClock *frame_clock,
+@@ -90,8 +96,9 @@ void clutter_frame_clock_remove_timeline (ClutterFrameClock *frame_clock,
  CLUTTER_EXPORT
  float clutter_frame_clock_get_refresh_rate (ClutterFrameClock *frame_clock);
  
@@ -342,10 +426,10 @@ index d3608e81c..06c5f7f28 100644
 +
  #endif /* CLUTTER_FRAME_H */
 diff --git a/clutter/clutter/clutter-stage-view.c b/clutter/clutter/clutter-stage-view.c
-index 9b7345983..f8da6e37c 100644
+index 8a82de71e..45d009352 100644
 --- a/clutter/clutter/clutter-stage-view.c
 +++ b/clutter/clutter/clutter-stage-view.c
-@@ -1189,8 +1189,9 @@ handle_frame_clock_frame (ClutterFrameClock *frame_clock,
+@@ -1190,8 +1190,9 @@ handle_frame_clock_frame (ClutterFrameClock *frame_clock,
  
        _clutter_stage_window_redraw_view (stage_window, view, &frame);
  
@@ -370,10 +454,10 @@ index dffe018d2..e0215f750 100644
 +
  #endif /* __COGL_ONSCREEN_PRIVATE_H */
 diff --git a/cogl/cogl/cogl-onscreen.c b/cogl/cogl/cogl-onscreen.c
-index cff5df50c..6f159cbb2 100644
+index ff9e1749a..b25b4af4a 100644
 --- a/cogl/cogl/cogl-onscreen.c
 +++ b/cogl/cogl/cogl-onscreen.c
-@@ -497,6 +497,14 @@ cogl_onscreen_pop_head_frame_info (CoglOnscreen *onscreen)
+@@ -510,6 +510,14 @@ cogl_onscreen_pop_head_frame_info (CoglOnscreen *onscreen)
    return g_queue_pop_head (&priv->pending_frame_infos);
  }
  
@@ -389,10 +473,10 @@ index cff5df50c..6f159cbb2 100644
  cogl_onscreen_add_frame_callback (CoglOnscreen *onscreen,
                                    CoglFrameCallback callback,
 diff --git a/src/backends/meta-stage-impl.c b/src/backends/meta-stage-impl.c
-index 28534ec81..bbed4fcf2 100644
+index c45aaf852..683f4ff6c 100644
 --- a/src/backends/meta-stage-impl.c
 +++ b/src/backends/meta-stage-impl.c
-@@ -670,6 +670,8 @@ meta_stage_impl_redraw_view (ClutterStageWindow *stage_window,
+@@ -720,6 +720,8 @@ meta_stage_impl_redraw_view (ClutterStageWindow *stage_window,
      {
        g_autoptr (GError) error = NULL;
  
@@ -401,8 +485,32 @@ index 28534ec81..bbed4fcf2 100644
        if (meta_stage_impl_scanout_view (stage_impl,
                                          stage_view,
                                          scanout,
+diff --git a/src/backends/native/meta-crtc-kms.c b/src/backends/native/meta-crtc-kms.c
+index 584a780ba..773b540b4 100644
+--- a/src/backends/native/meta-crtc-kms.c
++++ b/src/backends/native/meta-crtc-kms.c
+@@ -211,6 +211,7 @@ meta_crtc_kms_maybe_set_gamma (MetaCrtcKms   *crtc_kms,
+   MetaMonitorManagerNative *monitor_manager_native =
+     META_MONITOR_MANAGER_NATIVE (monitor_manager);
+   MetaKms *kms = meta_kms_device_get_kms (kms_device);
++  MetaKmsCrtc *kms_crtc = meta_crtc_kms_get_kms_crtc (crtc_kms);
+   MetaKmsUpdate *kms_update;
+   MetaKmsCrtcGamma *gamma;
+ 
+@@ -222,9 +223,9 @@ meta_crtc_kms_maybe_set_gamma (MetaCrtcKms   *crtc_kms,
+   if (!gamma)
+     return;
+ 
+-  kms_update = meta_kms_ensure_pending_update (kms, kms_device);
++  kms_update = meta_kms_ensure_pending_update_for_crtc (kms, kms_crtc);
+   meta_kms_update_set_crtc_gamma (kms_update,
+-                                  meta_crtc_kms_get_kms_crtc (crtc_kms),
++                                  kms_crtc,
+                                   gamma->size,
+                                   gamma->red,
+                                   gamma->green,
 diff --git a/src/backends/native/meta-cursor-renderer-native.c b/src/backends/native/meta-cursor-renderer-native.c
-index effa0851d..24e089a88 100644
+index df5862c4c..606fcad97 100644
 --- a/src/backends/native/meta-cursor-renderer-native.c
 +++ b/src/backends/native/meta-cursor-renderer-native.c
 @@ -64,19 +64,6 @@
@@ -507,6 +615,17 @@ index effa0851d..24e089a88 100644
  
    kms_crtc = meta_crtc_kms_get_kms_crtc (crtc_kms);
    kms_device = meta_kms_crtc_get_device (kms_crtc);
+@@ -343,8 +291,8 @@ assign_cursor_plane (MetaCursorRendererNative *native,
+     flags |= META_KMS_ASSIGN_PLANE_FLAG_FB_UNCHANGED;
+ 
+   kms_update =
+-    meta_kms_ensure_pending_update (meta_kms_device_get_kms (kms_device),
+-                                    meta_kms_crtc_get_device (kms_crtc));
++    meta_kms_ensure_pending_update_for_crtc (meta_kms_device_get_kms (kms_device),
++                                             kms_crtc);
+   plane_assignment = meta_kms_update_assign_plane (kms_update,
+                                                    kms_crtc,
+                                                    cursor_plane,
 @@ -365,13 +313,6 @@ assign_cursor_plane (MetaCursorRendererNative *native,
                                         native);
  
@@ -521,6 +640,15 @@ index effa0851d..24e089a88 100644
  }
  
  static float
+@@ -499,7 +440,7 @@ unset_crtc_cursor (MetaCursorRendererNative *native,
+       MetaKms *kms = meta_kms_device_get_kms (kms_device);
+       MetaKmsUpdate *kms_update;
+ 
+-      kms_update = meta_kms_ensure_pending_update (kms, kms_device);
++      kms_update = meta_kms_ensure_pending_update_for_crtc (kms, kms_crtc);
+       meta_kms_update_unassign_plane (kms_update, kms_crtc, cursor_plane);
+     }
+ 
 @@ -599,19 +540,7 @@ has_valid_cursor_sprite_buffer (MetaCursorSprite *cursor_sprite,
    if (!cursor_gpu_state)
      return FALSE;
@@ -542,7 +670,7 @@ index effa0851d..24e089a88 100644
  }
  
  static void
-@@ -1114,16 +1043,14 @@ unset_crtc_cursor_renderer_privates (MetaGpu       *gpu,
+@@ -1115,16 +1044,14 @@ unset_crtc_cursor_renderer_privates (MetaGpu       *gpu,
  static void
  cursor_gpu_state_free (MetaCursorNativeGpuState *cursor_gpu_state)
  {
@@ -561,7 +689,7 @@ index effa0851d..24e089a88 100644
    g_free (cursor_gpu_state);
  }
  
-@@ -1160,14 +1087,7 @@ invalidate_cursor_gpu_state (MetaCursorSprite *cursor_sprite)
+@@ -1161,14 +1088,7 @@ invalidate_cursor_gpu_state (MetaCursorSprite *cursor_sprite)
  
    g_hash_table_iter_init (&iter, cursor_priv->gpu_states);
    while (g_hash_table_iter_next (&iter, NULL, (gpointer *) &cursor_gpu_state))
@@ -577,7 +705,7 @@ index effa0851d..24e089a88 100644
  }
  
  static void
-@@ -1302,8 +1222,8 @@ load_cursor_sprite_gbm_buffer_for_gpu (MetaCursorRendererNative *native,
+@@ -1306,8 +1226,8 @@ load_cursor_sprite_gbm_buffer_for_gpu (MetaCursorRendererNative *native,
            return;
          }
  
@@ -588,7 +716,7 @@ index effa0851d..24e089a88 100644
      }
    else
      {
-@@ -1311,34 +1231,6 @@ load_cursor_sprite_gbm_buffer_for_gpu (MetaCursorRendererNative *native,
+@@ -1315,34 +1235,6 @@ load_cursor_sprite_gbm_buffer_for_gpu (MetaCursorRendererNative *native,
      }
  }
  
@@ -623,7 +751,7 @@ index effa0851d..24e089a88 100644
  static gboolean
  is_cursor_scale_and_transform_valid (MetaCursorRenderer *renderer,
                                       MetaCursorSprite   *cursor_sprite)
-@@ -1503,7 +1395,7 @@ realize_cursor_sprite_from_wl_buffer_for_gpu (MetaCursorRenderer      *renderer,
+@@ -1507,7 +1399,7 @@ realize_cursor_sprite_from_wl_buffer_for_gpu (MetaCursorRenderer      *renderer,
    if (!cursor_renderer_gpu_data || cursor_renderer_gpu_data->hw_cursor_broken)
      return;
  
@@ -632,7 +760,7 @@ index effa0851d..24e089a88 100644
        is_cursor_scale_and_transform_valid (renderer, cursor_sprite))
      return;
  
-@@ -1642,8 +1534,8 @@ realize_cursor_sprite_from_wl_buffer_for_gpu (MetaCursorRenderer      *renderer,
+@@ -1649,8 +1541,8 @@ realize_cursor_sprite_from_wl_buffer_for_gpu (MetaCursorRenderer      *renderer,
            return;
          }
  
@@ -643,7 +771,7 @@ index effa0851d..24e089a88 100644
      }
  }
  #endif
-@@ -1667,7 +1559,7 @@ realize_cursor_sprite_from_xcursor_for_gpu (MetaCursorRenderer      *renderer,
+@@ -1674,7 +1566,7 @@ realize_cursor_sprite_from_xcursor_for_gpu (MetaCursorRenderer      *renderer,
    if (!cursor_renderer_gpu_data || cursor_renderer_gpu_data->hw_cursor_broken)
      return;
  
@@ -653,7 +781,7 @@ index effa0851d..24e089a88 100644
      return;
  
 diff --git a/src/backends/native/meta-kms-crtc.c b/src/backends/native/meta-kms-crtc.c
-index 3e0506026..75109aa20 100644
+index 685a3737c..45c7eb78e 100644
 --- a/src/backends/native/meta-kms-crtc.c
 +++ b/src/backends/native/meta-kms-crtc.c
 @@ -32,6 +32,12 @@ typedef struct _MetaKmsCrtcPropTable
@@ -678,7 +806,7 @@ index 3e0506026..75109aa20 100644
  };
  
  G_DEFINE_TYPE (MetaKmsCrtc, meta_kms_crtc, G_TYPE_OBJECT)
-@@ -435,20 +443,86 @@ meta_kms_crtc_new (MetaKmsImplDevice  *impl_device,
+@@ -441,20 +449,91 @@ meta_kms_crtc_new (MetaKmsImplDevice  *impl_device,
    return crtc;
  }
  
@@ -694,7 +822,6 @@ index 3e0506026..75109aa20 100644
 +  if (plane_state == NULL)
 +    {
 +      plane_state = g_new0 (PlaneState, 1);
-+      g_return_if_fail (plane_state);
 +      g_hash_table_insert (crtc->plane_states, key, plane_state);
 +    }
 +
@@ -723,12 +850,18 @@ index 3e0506026..75109aa20 100644
 +  g_hash_table_foreach (crtc->plane_states, swap_plane_buffers, NULL);
 +}
 +
++void
++meta_kms_crtc_release_buffers (MetaKmsCrtc *crtc)
++{
++  g_hash_table_remove_all (crtc->plane_states);
++}
++
 +static void
 +meta_kms_crtc_dispose (GObject *object)
 +{
 +  MetaKmsCrtc *crtc = META_KMS_CRTC (object);
 +
-+  g_hash_table_remove_all (crtc->plane_states);
++  meta_kms_crtc_release_buffers (crtc);
 +
 +  G_OBJECT_CLASS (meta_kms_crtc_parent_class)->dispose (object);
 +}
@@ -765,7 +898,7 @@ index 3e0506026..75109aa20 100644
  }
  
  static void
-@@ -456,5 +530,6 @@ meta_kms_crtc_class_init (MetaKmsCrtcClass *klass)
+@@ -462,5 +541,6 @@ meta_kms_crtc_class_init (MetaKmsCrtcClass *klass)
  {
    GObjectClass *object_class = G_OBJECT_CLASS (klass);
  
@@ -773,7 +906,7 @@ index 3e0506026..75109aa20 100644
    object_class->finalize = meta_kms_crtc_finalize;
  }
 diff --git a/src/backends/native/meta-kms-crtc.h b/src/backends/native/meta-kms-crtc.h
-index 406ca3ac1..1a0d9f1b6 100644
+index 218bec9a1..29fdfcb5d 100644
 --- a/src/backends/native/meta-kms-crtc.h
 +++ b/src/backends/native/meta-kms-crtc.h
 @@ -25,6 +25,7 @@
@@ -781,10 +914,10 @@ index 406ca3ac1..1a0d9f1b6 100644
  
  #include "backends/native/meta-kms-types.h"
 +#include "backends/native/meta-drm-buffer.h"
+ #include "core/util-private.h"
  #include "meta/boxes.h"
  
- typedef struct _MetaKmsCrtcState
-@@ -76,4 +77,10 @@ MetaKmsCrtcGamma * meta_kms_crtc_gamma_new (MetaKmsCrtc    *crtc,
+@@ -82,4 +83,12 @@ MetaKmsCrtcGamma * meta_kms_crtc_gamma_new (MetaKmsCrtc    *crtc,
                                              const uint16_t *green,
                                              const uint16_t *blue);
  
@@ -794,38 +927,150 @@ index 406ca3ac1..1a0d9f1b6 100644
 +
 +void meta_kms_crtc_on_scanout_started (MetaKmsCrtc *crtc);
 +
++void meta_kms_crtc_release_buffers (MetaKmsCrtc *crtc);
++
  #endif /* META_KMS_CRTC_H */
 diff --git a/src/backends/native/meta-kms-impl-device-atomic.c b/src/backends/native/meta-kms-impl-device-atomic.c
-index 674a24902..718f4b3e1 100644
+index 73dd8e697..787d05acd 100644
 --- a/src/backends/native/meta-kms-impl-device-atomic.c
 +++ b/src/backends/native/meta-kms-impl-device-atomic.c
-@@ -495,6 +495,10 @@ process_plane_assignment (MetaKmsImplDevice  *impl_device,
-                                    error))
-             return FALSE;
-         }
+@@ -431,6 +431,7 @@ process_plane_assignment (MetaKmsImplDevice  *impl_device,
+ {
+   MetaKmsPlaneAssignment *plane_assignment = update_entry;
+   MetaKmsPlane *plane = plane_assignment->plane;
++  MetaKmsUpdateFlag flags = (MetaKmsUpdateFlag) user_data;
+   MetaDrmBuffer *buffer;
+   MetaKmsFbDamage *fb_damage;
+   uint32_t prop_id;
+@@ -586,6 +587,12 @@ process_plane_assignment (MetaKmsImplDevice  *impl_device,
+                                error))
+         return FALSE;
+     }
 +
-+      meta_kms_crtc_remember_plane_buffer (plane_assignment->crtc,
-+                                           meta_kms_plane_get_id (plane),
-+                                           buffer);
++  if (!(flags & META_KMS_UPDATE_FLAG_TEST_ONLY))
++    meta_kms_crtc_remember_plane_buffer (plane_assignment->crtc,
++                                         meta_kms_plane_get_id (plane),
++                                         buffer);
++
+   return TRUE;
+ }
+ 
+@@ -963,7 +970,7 @@ meta_kms_impl_device_atomic_process_update (MetaKmsImplDevice *impl_device,
+                         req,
+                         blob_ids,
+                         meta_kms_update_get_plane_assignments (update),
+-                        NULL,
++                        GUINT_TO_POINTER (flags),
+                         process_plane_assignment,
+                         &error))
+     goto err;
+diff --git a/src/backends/native/meta-kms-impl-device-simple.c b/src/backends/native/meta-kms-impl-device-simple.c
+index 882cd97cc..8aa78343a 100644
+--- a/src/backends/native/meta-kms-impl-device-simple.c
++++ b/src/backends/native/meta-kms-impl-device-simple.c
+@@ -470,6 +470,8 @@ process_mode_set (MetaKmsImplDevice  *impl_device,
+       return FALSE;
      }
-   else
+ 
++  meta_kms_crtc_on_scanout_started (crtc);
++
+   if (drm_mode)
      {
-@@ -522,6 +526,10 @@ process_plane_assignment (MetaKmsImplDevice  *impl_device,
-                                    error))
-             return FALSE;
+       g_hash_table_replace (impl_device_simple->cached_mode_sets,
+@@ -534,7 +536,7 @@ is_timestamp_earlier_than (uint64_t ts1,
+ typedef struct _RetryPageFlipData
+ {
+   MetaKmsCrtc *crtc;
+-  uint32_t fb_id;
++  MetaDrmBuffer *fb;
+   MetaKmsPageFlipData *page_flip_data;
+   float refresh_rate;
+   uint64_t retry_time_us;
+@@ -547,6 +549,7 @@ retry_page_flip_data_free (RetryPageFlipData *retry_page_flip_data)
+   g_assert (!retry_page_flip_data->page_flip_data);
+   g_clear_pointer (&retry_page_flip_data->custom_page_flip,
+                    meta_kms_custom_page_flip_free);
++  g_clear_object (&retry_page_flip_data->fb);
+   g_free (retry_page_flip_data);
+ }
+ 
+@@ -614,16 +617,21 @@ retry_page_flips (gpointer user_data)
          }
+       else
+         {
++          uint32_t fb_id =
++            retry_page_flip_data->fb ?
++            meta_drm_buffer_get_fb_id (retry_page_flip_data->fb) :
++            0;
 +
-+      meta_kms_crtc_remember_plane_buffer (plane_assignment->crtc,
-+                                           meta_kms_plane_get_id (plane),
-+                                           NULL);
+           meta_topic (META_DEBUG_KMS,
+                       "[simple] Retrying page flip on CRTC %u (%s) with %u",
+                       meta_kms_crtc_get_id (crtc),
+                       meta_kms_impl_device_get_path (impl_device),
+-                      retry_page_flip_data->fb_id);
++                      fb_id);
+ 
+           fd = meta_kms_impl_device_get_fd (impl_device);
+           ret = drmModePageFlip (fd,
+                                  meta_kms_crtc_get_id (crtc),
+-                                 retry_page_flip_data->fb_id,
++                                 fb_id,
+                                  DRM_MODE_PAGE_FLIP_EVENT,
+                                  retry_page_flip_data->page_flip_data);
+         }
+@@ -710,7 +718,7 @@ retry_page_flips (gpointer user_data)
+ static void
+ schedule_retry_page_flip (MetaKmsImplDeviceSimple *impl_device_simple,
+                           MetaKmsCrtc             *crtc,
+-                          uint32_t                 fb_id,
++                          MetaDrmBuffer           *fb,
+                           float                    refresh_rate,
+                           MetaKmsPageFlipData     *page_flip_data,
+                           MetaKmsCustomPageFlip   *custom_page_flip)
+@@ -725,7 +733,7 @@ schedule_retry_page_flip (MetaKmsImplDeviceSimple *impl_device_simple,
+   retry_page_flip_data = g_new0 (RetryPageFlipData, 1);
+   *retry_page_flip_data = (RetryPageFlipData) {
+     .crtc = crtc,
+-    .fb_id = fb_id,
++    .fb = fb ? g_object_ref (fb) : NULL,
+     .page_flip_data = page_flip_data,
+     .refresh_rate = refresh_rate,
+     .retry_time_us = retry_time_us,
+@@ -859,6 +867,8 @@ mode_set_fallback (MetaKmsImplDeviceSimple  *impl_device_simple,
+       return FALSE;
      }
  
-   if (plane_assignment->rotation)
-diff --git a/src/backends/native/meta-kms-impl-device-simple.c b/src/backends/native/meta-kms-impl-device-simple.c
-index 28d512720..2f3c99928 100644
---- a/src/backends/native/meta-kms-impl-device-simple.c
-+++ b/src/backends/native/meta-kms-impl-device-simple.c
-@@ -1275,7 +1275,7 @@ process_plane_assignment (MetaKmsImplDevice       *impl_device,
++  meta_kms_crtc_on_scanout_started (crtc);
++
+   if (!impl_device_simple->mode_set_fallback_feedback_source)
+     {
+       GSource *source;
+@@ -983,20 +993,20 @@ dispatch_page_flip (MetaKmsImplDevice    *impl_device,
+       cached_mode_set = get_cached_mode_set (impl_device_simple, crtc);
+       if (cached_mode_set)
+         {
+-          uint32_t fb_id;
++          MetaDrmBuffer *fb;
+           drmModeModeInfo *drm_mode;
+           float refresh_rate;
+ 
+           if (plane_assignment)
+-            fb_id = meta_drm_buffer_get_fb_id (plane_assignment->buffer);
++            fb = plane_assignment->buffer;
+           else
+-            fb_id = 0;
++            fb = NULL;
+           drm_mode = cached_mode_set->drm_mode;
+           refresh_rate = meta_calculate_drm_mode_refresh_rate (drm_mode);
+           meta_kms_impl_device_hold_fd (impl_device);
+           schedule_retry_page_flip (impl_device_simple,
+                                     crtc,
+-                                    fb_id,
++                                    fb,
+                                     refresh_rate,
+                                     page_flip_data,
+                                     g_steal_pointer (&custom_page_flip));
+@@ -1290,7 +1300,7 @@ process_plane_assignment (MetaKmsImplDevice       *impl_device,
      {
      case META_KMS_PLANE_TYPE_PRIMARY:
        /* Handled as part of the mode-set and page flip. */
@@ -834,7 +1079,7 @@ index 28d512720..2f3c99928 100644
      case META_KMS_PLANE_TYPE_CURSOR:
        if (!process_cursor_plane_assignment (impl_device, update,
                                              plane_assignment,
-@@ -1289,7 +1289,7 @@ process_plane_assignment (MetaKmsImplDevice       *impl_device,
+@@ -1304,7 +1314,7 @@ process_plane_assignment (MetaKmsImplDevice       *impl_device,
          }
        else
          {
@@ -843,7 +1088,7 @@ index 28d512720..2f3c99928 100644
          }
      case META_KMS_PLANE_TYPE_OVERLAY:
        error = g_error_new_literal (G_IO_ERROR, G_IO_ERROR_FAILED,
-@@ -1302,6 +1302,12 @@ process_plane_assignment (MetaKmsImplDevice       *impl_device,
+@@ -1317,6 +1327,12 @@ process_plane_assignment (MetaKmsImplDevice       *impl_device,
      }
  
    g_assert_not_reached ();
@@ -856,6 +1101,23 @@ index 28d512720..2f3c99928 100644
  }
  
  static gboolean
+diff --git a/src/backends/native/meta-kms-impl-device.c b/src/backends/native/meta-kms-impl-device.c
+index b05bf5fda..1177707fa 100644
+--- a/src/backends/native/meta-kms-impl-device.c
++++ b/src/backends/native/meta-kms-impl-device.c
+@@ -1022,8 +1022,12 @@ meta_kms_impl_device_init_mode_setting (MetaKmsImplDevice  *impl_device,
+ void
+ meta_kms_impl_device_prepare_shutdown (MetaKmsImplDevice *impl_device)
+ {
++  MetaKmsImplDevicePrivate *priv =
++    meta_kms_impl_device_get_instance_private (impl_device);
+   MetaKmsImplDeviceClass *klass = META_KMS_IMPL_DEVICE_GET_CLASS (impl_device);
+ 
++  g_list_foreach (priv->crtcs, (GFunc) meta_kms_crtc_release_buffers, NULL);
++
+   if (klass->prepare_shutdown)
+     klass->prepare_shutdown (impl_device);
+ 
 diff --git a/src/backends/native/meta-kms-page-flip.c b/src/backends/native/meta-kms-page-flip.c
 index 817f4e7c8..148d23740 100644
 --- a/src/backends/native/meta-kms-page-flip.c
@@ -877,11 +1139,36 @@ index 817f4e7c8..148d23740 100644
    for (l = page_flip_data->closures; l; l = l->next)
      {
        MetaKmsPageFlipClosure *closure = l->data;
+diff --git a/src/backends/native/meta-kms-update-private.h b/src/backends/native/meta-kms-update-private.h
+index a613cbc5d..1d964ff21 100644
+--- a/src/backends/native/meta-kms-update-private.h
++++ b/src/backends/native/meta-kms-update-private.h
+@@ -132,6 +132,12 @@ uint64_t meta_kms_update_get_sequence_number (MetaKmsUpdate *update);
+ META_EXPORT_TEST
+ MetaKmsDevice * meta_kms_update_get_device (MetaKmsUpdate *update);
+ 
++gboolean meta_kms_update_includes_crtc (MetaKmsUpdate *update,
++                                        MetaKmsCrtc   *crtc);
++
++void meta_kms_update_include_crtc (MetaKmsUpdate *update,
++                                   MetaKmsCrtc   *crtc);
++
+ void meta_kms_plane_assignment_set_rotation (MetaKmsPlaneAssignment *plane_assignment,
+                                              uint64_t                rotation);
+ 
 diff --git a/src/backends/native/meta-kms-update.c b/src/backends/native/meta-kms-update.c
-index 71e5b423f..a98e8ade6 100644
+index 53fc92eb8..1e43f3f0f 100644
 --- a/src/backends/native/meta-kms-update.c
 +++ b/src/backends/native/meta-kms-update.c
-@@ -140,6 +140,7 @@ static void
+@@ -31,6 +31,7 @@
+ struct _MetaKmsUpdate
+ {
+   MetaKmsDevice *device;
++  GHashTable *crtcs;
+ 
+   gboolean is_locked;
+   uint64_t sequence_number;
+@@ -149,6 +150,7 @@ static void
  meta_kms_plane_assignment_free (MetaKmsPlaneAssignment *plane_assignment)
  {
    g_clear_pointer (&plane_assignment->fb_damage, meta_kms_fb_damage_free);
@@ -889,7 +1176,7 @@ index 71e5b423f..a98e8ade6 100644
    g_free (plane_assignment);
  }
  
-@@ -220,7 +221,7 @@ meta_kms_update_assign_plane (MetaKmsUpdate          *update,
+@@ -228,7 +230,7 @@ meta_kms_update_assign_plane (MetaKmsUpdate          *update,
      .update = update,
      .crtc = crtc,
      .plane = plane,
@@ -898,74 +1185,281 @@ index 71e5b423f..a98e8ade6 100644
      .src_rect = src_rect,
      .dst_rect = dst_rect,
      .flags = flags,
+@@ -237,6 +239,8 @@ meta_kms_update_assign_plane (MetaKmsUpdate          *update,
+   update->plane_assignments = g_list_prepend (update->plane_assignments,
+                                               plane_assignment);
+ 
++  g_hash_table_insert (update->crtcs, crtc, NULL);
++
+   return plane_assignment;
+ }
+ 
+@@ -262,6 +266,8 @@ meta_kms_update_unassign_plane (MetaKmsUpdate *update,
+   update->plane_assignments = g_list_prepend (update->plane_assignments,
+                                               plane_assignment);
+ 
++  g_hash_table_insert (update->crtcs, crtc, NULL);
++
+   return plane_assignment;
+ }
+ 
+@@ -284,6 +290,8 @@ meta_kms_update_mode_set (MetaKmsUpdate *update,
+   };
+ 
+   update->mode_sets = g_list_prepend (update->mode_sets, mode_set);
++
++  g_hash_table_insert (update->crtcs, crtc, NULL);
+ }
+ 
+ static MetaKmsConnectorUpdate *
+@@ -402,6 +410,8 @@ meta_kms_update_set_crtc_gamma (MetaKmsUpdate  *update,
+   gamma = meta_kms_crtc_gamma_new (crtc, size, red, green, blue);
+ 
+   update->crtc_gammas = g_list_prepend (update->crtc_gammas, gamma);
++
++  g_hash_table_insert (update->crtcs, crtc, NULL);
+ }
+ 
+ void
+@@ -665,6 +675,20 @@ meta_kms_update_get_device (MetaKmsUpdate *update)
+   return update->device;
+ }
+ 
++gboolean
++meta_kms_update_includes_crtc (MetaKmsUpdate *update,
++                               MetaKmsCrtc   *crtc)
++{
++  return g_hash_table_lookup_extended (update->crtcs, crtc, NULL, NULL);
++}
++
++void
++meta_kms_update_include_crtc (MetaKmsUpdate *update,
++                              MetaKmsCrtc   *crtc)
++{
++  g_hash_table_insert (update->crtcs, crtc, NULL);
++}
++
+ MetaKmsCustomPageFlip *
+ meta_kms_update_take_custom_page_flip_func (MetaKmsUpdate *update)
+ {
+@@ -693,12 +717,15 @@ meta_kms_update_new (MetaKmsDevice *device)
+   update->device = device;
+   update->sequence_number = sequence_number++;
+ 
++  update->crtcs = g_hash_table_new (NULL, NULL);
++
+   return update;
+ }
+ 
+ void
+ meta_kms_update_free (MetaKmsUpdate *update)
+ {
++  g_hash_table_destroy (update->crtcs);
+   g_list_free_full (update->result_listeners,
+                     (GDestroyNotify) meta_kms_result_listener_free);
+   g_list_free_full (update->plane_assignments,
 diff --git a/src/backends/native/meta-kms.c b/src/backends/native/meta-kms.c
-index 0750278ae..061460b38 100644
+index 052ec8a65..9acc17b0d 100644
 --- a/src/backends/native/meta-kms.c
 +++ b/src/backends/native/meta-kms.c
-@@ -177,6 +177,8 @@ struct _MetaKms
+@@ -23,6 +23,7 @@
+ #include "backends/native/meta-kms-private.h"
  
-   GList *pending_callbacks;
-   guint callback_source_id;
-+
-+  gboolean shutting_down;
- };
+ #include "backends/native/meta-backend-native.h"
++#include "backends/native/meta-kms-crtc.h"
+ #include "backends/native/meta-kms-device-private.h"
+ #include "backends/native/meta-kms-impl.h"
+ #include "backends/native/meta-kms-update-private.h"
+@@ -181,6 +182,11 @@ struct _MetaKms
  
  G_DEFINE_TYPE (MetaKms, meta_kms, G_TYPE_OBJECT)
-@@ -277,6 +279,9 @@ meta_kms_post_pending_update_sync (MetaKms           *kms,
-   COGL_TRACE_BEGIN_SCOPED (MetaKmsPostUpdateSync,
-                            "KMS (post update)");
  
-+  if (kms->shutting_down)
-+    return NULL;
++static MetaKmsFeedback *
++meta_kms_post_update_sync (MetaKms           *kms,
++                           MetaKmsUpdate     *update,
++                           MetaKmsUpdateFlag  flags);
 +
-   update = meta_kms_take_pending_update (kms, device);
-   if (!update)
-     return NULL;
-@@ -757,6 +762,7 @@ prepare_shutdown_in_impl (MetaKmsImpl  *impl,
  void
- meta_kms_prepare_shutdown (MetaKms *kms)
+ meta_kms_discard_pending_updates (MetaKms *kms)
  {
-+  kms->shutting_down = TRUE;
-   meta_kms_run_impl_task_sync (kms, prepare_shutdown_in_impl, NULL, NULL);
-   flush_callbacks (kms);
+@@ -247,12 +253,105 @@ meta_kms_take_pending_update (MetaKms       *kms,
+   return NULL;
  }
-diff --git a/src/backends/native/meta-onscreen-native.c b/src/backends/native/meta-onscreen-native.c
-index 00b2d9f89..eb1e7412a 100644
---- a/src/backends/native/meta-onscreen-native.c
-+++ b/src/backends/native/meta-onscreen-native.c
-@@ -46,6 +46,8 @@
- #include "backends/native/meta-renderer-native-gles3.h"
- #include "backends/native/meta-renderer-native-private.h"
  
-+#define MAX_CONCURRENT_POSTS 1
++MetaKmsUpdate *
++meta_kms_ensure_pending_update_for_crtc (MetaKms     *kms,
++                                         MetaKmsCrtc *crtc)
++{
++  MetaKmsUpdate *update;
++
++  update = meta_kms_get_pending_update_for_crtc (kms, crtc);
++  if (update == NULL)
++    {
++      update = meta_kms_update_new (meta_kms_crtc_get_device (crtc));
++      meta_kms_update_include_crtc (update, crtc);
++      meta_kms_add_pending_update (kms, update);
++    }
++
++  return update;
++}
++
++static MetaKmsUpdate *
++meta_kms_find_compatible_update_for_crtc (MetaKms     *kms,
++                                          MetaKmsCrtc *crtc,
++                                          gboolean     take)
++{
++  MetaKmsDevice *device;
++  MetaKmsUpdate *update;
++  GList *l;
++
++  for (l = kms->pending_updates; l; l = l->next)
++    {
++      update = l->data;
++      if (meta_kms_update_includes_crtc (update, crtc))
++        goto found;
++    }
++
++  device = meta_kms_crtc_get_device (crtc);
++
++  for (l = kms->pending_updates; l; l = l->next)
++    {
++      update = l->data;
++      if (meta_kms_update_get_device (update) == device &&
++          meta_kms_update_get_mode_sets (update))
++        goto found;
++    }
++
++  return NULL;
++
++found:
++  if (take)
++    kms->pending_updates = g_list_delete_link (kms->pending_updates, l);
++  return update;
++}
++
++MetaKmsUpdate *
++meta_kms_get_pending_update_for_crtc (MetaKms     *kms,
++                                      MetaKmsCrtc *crtc)
++{
++  return meta_kms_find_compatible_update_for_crtc (kms, crtc, FALSE);
++}
 +
- typedef enum _MetaSharedFramebufferImportStatus
++static MetaKmsUpdate *
++meta_kms_take_pending_update_for_crtc (MetaKms     *kms,
++                                       MetaKmsCrtc *crtc)
++{
++  return meta_kms_find_compatible_update_for_crtc (kms, crtc, TRUE);
++}
++
+ MetaKmsFeedback *
+ meta_kms_post_pending_update_sync (MetaKms           *kms,
+                                    MetaKmsDevice     *device,
+                                    MetaKmsUpdateFlag  flags)
  {
-   /* Not tried importing yet. */
-@@ -65,7 +67,6 @@ typedef struct _MetaOnscreenNativeSecondaryGpuState
+   MetaKmsUpdate *update;
++
++  update = meta_kms_take_pending_update (kms, device);
++  if (!update)
++    return NULL;
++
++  return meta_kms_post_update_sync (kms, update, flags);
++}
++
++MetaKmsFeedback *
++meta_kms_post_pending_update_for_crtc_sync (MetaKms           *kms,
++                                            MetaKmsCrtc       *crtc,
++                                            MetaKmsUpdateFlag  flags)
++{
++  MetaKmsUpdate *update;
++
++  update = meta_kms_take_pending_update_for_crtc (kms, crtc);
++  if (!update)
++    return NULL;
++
++  return meta_kms_post_update_sync (kms, update, flags);
++}
++
++static MetaKmsFeedback *
++meta_kms_post_update_sync (MetaKms           *kms,
++                           MetaKmsUpdate     *update,
++                           MetaKmsUpdateFlag  flags)
++{
++  MetaKmsDevice *device = meta_kms_update_get_device (update);
+   MetaKmsFeedback *feedback;
+   GList *result_listeners;
+   GList *l;
+@@ -260,10 +359,6 @@ meta_kms_post_pending_update_sync (MetaKms           *kms,
+   COGL_TRACE_BEGIN_SCOPED (MetaKmsPostUpdateSync,
+                            "KMS (post update)");
+ 
+-  update = meta_kms_take_pending_update (kms, device);
+-  if (!update)
+-    return NULL;
+-
+   meta_kms_update_lock (update);
+ 
+   feedback = meta_kms_device_process_update_sync (device, update, flags);
+diff --git a/src/backends/native/meta-kms.h b/src/backends/native/meta-kms.h
+index bd9fe5cea..84f1bed49 100644
+--- a/src/backends/native/meta-kms.h
++++ b/src/backends/native/meta-kms.h
+@@ -39,9 +39,15 @@ void meta_kms_discard_pending_updates (MetaKms *kms);
+ MetaKmsUpdate * meta_kms_ensure_pending_update (MetaKms       *kms,
+                                                 MetaKmsDevice *device);
+ 
++MetaKmsUpdate * meta_kms_ensure_pending_update_for_crtc (MetaKms     *kms,
++                                                         MetaKmsCrtc *crtc);
++
+ MetaKmsUpdate * meta_kms_get_pending_update (MetaKms       *kms,
+                                              MetaKmsDevice *device);
+ 
++MetaKmsUpdate * meta_kms_get_pending_update_for_crtc (MetaKms     *kms,
++                                                      MetaKmsCrtc *crtc);
++
+ MetaKmsFeedback * meta_kms_post_pending_update_sync (MetaKms           *kms,
+                                                      MetaKmsDevice     *device,
+                                                      MetaKmsUpdateFlag  flags);
+@@ -49,6 +55,10 @@ MetaKmsFeedback * meta_kms_post_pending_update_sync (MetaKms           *kms,
+ MetaKmsFeedback * meta_kms_post_test_update_sync (MetaKms       *kms,
+                                                   MetaKmsUpdate *update);
+ 
++MetaKmsFeedback * meta_kms_post_pending_update_for_crtc_sync (MetaKms           *kms,
++                                                              MetaKmsCrtc       *device,
++                                                              MetaKmsUpdateFlag  flags);
++
+ void meta_kms_discard_pending_page_flips (MetaKms *kms);
+ 
+ void meta_kms_notify_modes_set (MetaKms *kms);
+diff --git a/src/backends/native/meta-onscreen-native.c b/src/backends/native/meta-onscreen-native.c
+index 3eb550319..24d7f7385 100644
+--- a/src/backends/native/meta-onscreen-native.c
++++ b/src/backends/native/meta-onscreen-native.c
+@@ -67,13 +67,12 @@ typedef struct _MetaOnscreenNativeSecondaryGpuState
  
    struct {
      struct gbm_surface *surface;
 -    MetaDrmBuffer *current_fb;
-     MetaDrmBuffer *next_fb;
+-    MetaDrmBuffer *next_fb;
    } gbm;
  
-@@ -92,8 +93,13 @@ struct _MetaOnscreenNative
+   struct {
+     MetaDrmBufferDumb *current_dumb_fb;
+     MetaDrmBufferDumb *dumb_fbs[2];
++    MetaDrmBuffer *source_fbs[2];
+   } cpu;
+ 
+   gboolean noted_primary_gpu_copy_ok;
+@@ -94,8 +93,8 @@ struct _MetaOnscreenNative
  
    struct {
      struct gbm_surface *surface;
 -    MetaDrmBuffer *current_fb;
      MetaDrmBuffer *next_fb;
-+
-+    struct {
-+      uint32_t format;
-+      uint32_t stride;
-+      uint64_t modifier;
-+    } last_flip;
++    MetaDrmBuffer *stalled_fb;
    } gbm;
  
  #ifdef HAVE_EGL_DEVICE
-@@ -105,69 +111,25 @@ struct _MetaOnscreenNative
+@@ -107,69 +106,25 @@ struct _MetaOnscreenNative
  #endif
  
    MetaRendererView *view;
@@ -981,7 +1475,7 @@ index 00b2d9f89..eb1e7412a 100644
                 COGL_TYPE_ONSCREEN_EGL)
  
 +static void
-+post_latest_swap (CoglOnscreen *onscreen);
++try_post_latest_swap (CoglOnscreen *onscreen);
 +
  static gboolean
  init_secondary_gpu_state (MetaRendererNative  *renderer_native,
@@ -1044,7 +1538,7 @@ index 00b2d9f89..eb1e7412a 100644
  static void
  maybe_update_frame_info (MetaCrtc         *crtc,
                           CoglFrameInfo    *frame_info,
-@@ -203,7 +165,7 @@ meta_onscreen_native_notify_frame_complete (CoglOnscreen *onscreen)
+@@ -205,7 +160,7 @@ meta_onscreen_native_notify_frame_complete (CoglOnscreen *onscreen)
  
    info = cogl_onscreen_pop_head_frame_info (onscreen);
  
@@ -1053,102 +1547,479 @@ index 00b2d9f89..eb1e7412a 100644
  
    _cogl_onscreen_notify_frame_sync (onscreen, info);
    _cogl_onscreen_notify_complete (onscreen, info);
-@@ -230,7 +192,7 @@ notify_view_crtc_presented (MetaRendererView *view,
+@@ -234,7 +189,7 @@ notify_view_crtc_presented (MetaRendererView *view,
    maybe_update_frame_info (crtc, frame_info, time_us, flags, sequence);
  
    meta_onscreen_native_notify_frame_complete (onscreen);
 -  meta_onscreen_native_swap_drm_fb (onscreen);
-+  post_latest_swap (onscreen);
++  try_post_latest_swap (onscreen);
  }
  
  static int64_t
-@@ -292,6 +254,7 @@ page_flip_feedback_ready (MetaKmsCrtc *kms_crtc,
+@@ -296,6 +251,7 @@ page_flip_feedback_ready (MetaKmsCrtc *kms_crtc,
    frame_info->flags |= COGL_FRAME_INFO_FLAG_SYMBOLIC;
  
    meta_onscreen_native_notify_frame_complete (onscreen);
-+  post_latest_swap (onscreen);
++  try_post_latest_swap (onscreen);
  }
  
  static void
-@@ -341,7 +304,7 @@ page_flip_feedback_discarded (MetaKmsCrtc  *kms_crtc,
+@@ -345,7 +301,7 @@ page_flip_feedback_discarded (MetaKmsCrtc  *kms_crtc,
    frame_info->flags |= COGL_FRAME_INFO_FLAG_SYMBOLIC;
  
    meta_onscreen_native_notify_frame_complete (onscreen);
 -  meta_onscreen_native_swap_drm_fb (onscreen);
-+  post_latest_swap (onscreen);
++  try_post_latest_swap (onscreen);
  }
  
  static const MetaKmsPageFlipListenerVtable page_flip_listener_vtable = {
-@@ -405,11 +368,10 @@ meta_onscreen_native_dummy_power_save_page_flip (CoglOnscreen *onscreen)
+@@ -406,18 +362,40 @@ custom_egl_stream_page_flip (gpointer custom_page_flip_data,
+ }
+ #endif /* HAVE_EGL_DEVICE */
+ 
+-void
+-meta_onscreen_native_dummy_power_save_page_flip (CoglOnscreen *onscreen)
++static void
++drop_stalled_swap (CoglOnscreen *onscreen)
  {
++  MetaOnscreenNative *onscreen_native = META_ONSCREEN_NATIVE (onscreen);
    CoglFrameInfo *frame_info;
  
 -  meta_onscreen_native_swap_drm_fb (onscreen);
--
++  /* Remember we can't compare stalled_fb because it's not used by
++   * META_RENDERER_NATIVE_MODE_EGL_DEVICE. So we judge stalled to be whenever
++   * swaps_pending > 1.
++   */
++  if (onscreen_native->swaps_pending <= 1)
++    return;
++
++  onscreen_native->swaps_pending--;
++
++  g_clear_object (&onscreen_native->gbm.stalled_fb);
+ 
    frame_info = cogl_onscreen_peek_tail_frame_info (onscreen);
    frame_info->flags |= COGL_FRAME_INFO_FLAG_SYMBOLIC;
    meta_onscreen_native_notify_frame_complete (onscreen);
-+  post_latest_swap (onscreen);
  }
  
++void
++meta_onscreen_native_dummy_power_save_page_flip (CoglOnscreen *onscreen)
++{
++  drop_stalled_swap (onscreen);
++
++  /* If the monitor just woke up and the shell is fully idle (has nothing
++   * more to swap) then we just woke to an indefinitely black screen. Let's
++   * fix that using the last swap (which is never classified as "stalled").
++   */
++  try_post_latest_swap (onscreen);
++}
++
  static void
-@@ -431,7 +393,7 @@ meta_onscreen_native_flip_crtc (CoglOnscreen                *onscreen,
+ meta_onscreen_native_flip_crtc (CoglOnscreen                *onscreen,
+                                 MetaRendererView            *view,
+@@ -436,8 +414,7 @@ meta_onscreen_native_flip_crtc (CoglOnscreen                *onscreen,
+   MetaKmsDevice *kms_device;
    MetaKms *kms;
    MetaKmsUpdate *kms_update;
-   MetaOnscreenNativeSecondaryGpuState *secondary_gpu_state = NULL;
+-  MetaOnscreenNativeSecondaryGpuState *secondary_gpu_state = NULL;
 -  MetaDrmBuffer *buffer;
 +  g_autoptr (MetaDrmBuffer) buffer = NULL;
    MetaKmsPlaneAssignment *plane_assignment;
  
    COGL_TRACE_BEGIN_SCOPED (MetaOnscreenNativeFlipCrtcs,
-@@ -451,12 +413,14 @@ meta_onscreen_native_flip_crtc (CoglOnscreen                *onscreen,
+@@ -446,7 +423,7 @@ meta_onscreen_native_flip_crtc (CoglOnscreen                *onscreen,
+   gpu_kms = META_GPU_KMS (meta_crtc_get_gpu (crtc));
+   kms_device = meta_gpu_kms_get_kms_device (gpu_kms);
+   kms = meta_kms_device_get_kms (kms_device);
+-  kms_update = meta_kms_ensure_pending_update (kms, kms_device);
++  kms_update = meta_kms_ensure_pending_update_for_crtc (kms, kms_crtc);
+ 
+   g_assert (meta_gpu_kms_is_crtc_active (gpu_kms, crtc));
+ 
+@@ -455,15 +432,7 @@ meta_onscreen_native_flip_crtc (CoglOnscreen                *onscreen,
+   switch (renderer_gpu_data->mode)
+     {
      case META_RENDERER_NATIVE_MODE_GBM:
-       if (gpu_kms == render_gpu)
-         {
+-      if (gpu_kms == render_gpu)
+-        {
 -          buffer = onscreen_native->gbm.next_fb;
-+          buffer = g_object_ref (onscreen_native->gbm.next_fb);
-+          g_clear_object (&onscreen_native->gbm.next_fb);
-         }
-       else
-         {
-           secondary_gpu_state = onscreen_native->secondary_gpu_state;
+-        }
+-      else
+-        {
+-          secondary_gpu_state = onscreen_native->secondary_gpu_state;
 -          buffer = secondary_gpu_state->gbm.next_fb;
-+          buffer = g_object_ref (secondary_gpu_state->gbm.next_fb);
-+          g_clear_object (&secondary_gpu_state->gbm.next_fb);
-         }
+-        }
++      buffer = g_steal_pointer (&onscreen_native->gbm.next_fb);
  
        plane_assignment = meta_crtc_kms_assign_primary_plane (crtc_kms,
-@@ -468,6 +432,21 @@ meta_onscreen_native_flip_crtc (CoglOnscreen                *onscreen,
-           meta_kms_plane_assignment_set_fb_damage (plane_assignment,
-                                                    rectangles, n_rectangles);
-         }
+                                                              buffer,
+@@ -509,7 +478,7 @@ meta_onscreen_native_set_crtc_mode (CoglOnscreen              *onscreen,
+   COGL_TRACE_BEGIN_SCOPED (MetaOnscreenNativeSetCrtcModes,
+                            "Onscreen (set CRTC modes)");
+ 
+-  kms_update = meta_kms_ensure_pending_update (kms, kms_device);
++  kms_update = meta_kms_ensure_pending_update_for_crtc (kms, kms_crtc);
+ 
+   switch (renderer_gpu_data->mode)
+     {
+@@ -535,13 +504,41 @@ meta_onscreen_native_set_crtc_mode (CoglOnscreen              *onscreen,
+                                  kms_update);
+ }
+ 
++static void
++hold_primary_gpu_fb_for_secondary_gpu_scanout (MetaOnscreenNativeSecondaryGpuState *secondary_gpu_state,
++                                               MetaDrmBuffer                       *primary_gpu_fb,
++                                               MetaDrmBuffer                       *secondary_gpu_fb)
++{
++  if (META_IS_DRM_BUFFER_DUMB (secondary_gpu_fb))
++    {
++      MetaDrmBufferDumb *dumb_fb = META_DRM_BUFFER_DUMB (secondary_gpu_fb);
++      int i;
++      const int n = G_N_ELEMENTS (secondary_gpu_state->cpu.dumb_fbs);
 +
-+      if (META_IS_DRM_BUFFER_GBM (buffer))
++      for (i = 0; i < n; i++)
 +        {
-+          MetaDrmBufferGbm *buffer_gbm = META_DRM_BUFFER_GBM (buffer);
-+          struct gbm_bo *gbm_bo = meta_drm_buffer_gbm_get_bo (buffer_gbm);
++          if (dumb_fb == secondary_gpu_state->cpu.dumb_fbs[i])
++            {
++              g_set_object (&secondary_gpu_state->cpu.source_fbs[i],
++                            primary_gpu_fb);
++              break;
++            }
++        }
 +
-+          onscreen_native->gbm.last_flip.format = gbm_bo_get_format (gbm_bo);
-+          onscreen_native->gbm.last_flip.modifier = gbm_bo_get_modifier (gbm_bo);
-+          onscreen_native->gbm.last_flip.stride = gbm_bo_get_stride (gbm_bo);
++      g_warn_if_fail (i < n);
++    }
++}
 +
-+          g_object_set_data_full (G_OBJECT (buffer_gbm),
-+                                  "gbm_surface owner",
-+                                  g_object_ref (onscreen),
-+                                  (GDestroyNotify) g_object_unref);
-+        }
-       break;
-     case META_RENDERER_NATIVE_MODE_SURFACELESS:
-       g_assert_not_reached ();
-@@ -556,7 +535,6 @@ secondary_gpu_state_free (MetaOnscreenNativeSecondaryGpuState *secondary_gpu_sta
+ static void
+ secondary_gpu_release_dumb (MetaOnscreenNativeSecondaryGpuState *secondary_gpu_state)
+ {
+   unsigned i;
+ 
+   for (i = 0; i < G_N_ELEMENTS (secondary_gpu_state->cpu.dumb_fbs); i++)
+-    g_clear_object (&secondary_gpu_state->cpu.dumb_fbs[i]);
++    {
++      g_clear_object (&secondary_gpu_state->cpu.dumb_fbs[i]);
++      g_clear_object (&secondary_gpu_state->cpu.source_fbs[i]);
++    }
+ }
+ 
+ static void
+@@ -566,8 +563,6 @@ secondary_gpu_state_free (MetaOnscreenNativeSecondaryGpuState *secondary_gpu_sta
                                  NULL);
      }
  
 -  g_clear_object (&secondary_gpu_state->gbm.current_fb);
-   g_clear_object (&secondary_gpu_state->gbm.next_fb);
+-  g_clear_object (&secondary_gpu_state->gbm.next_fb);
    g_clear_pointer (&secondary_gpu_state->gbm.surface, gbm_surface_destroy);
  
-@@ -1004,12 +982,6 @@ meta_onscreen_native_swap_buffers_with_damage (CoglOnscreen  *onscreen,
+   secondary_gpu_release_dumb (secondary_gpu_state);
+@@ -575,11 +570,11 @@ secondary_gpu_state_free (MetaOnscreenNativeSecondaryGpuState *secondary_gpu_sta
+   g_free (secondary_gpu_state);
+ }
+ 
+-static gboolean
++static MetaDrmBuffer *
+ import_shared_framebuffer (CoglOnscreen                        *onscreen,
+-                           MetaOnscreenNativeSecondaryGpuState *secondary_gpu_state)
++                           MetaOnscreenNativeSecondaryGpuState *secondary_gpu_state,
++                           MetaDrmBuffer                       *primary_gpu_fb)
+ {
+-  MetaOnscreenNative *onscreen_native = META_ONSCREEN_NATIVE (onscreen);
+   MetaRenderDevice *render_device;
+   g_autoptr (GError) error = NULL;
+   MetaDrmBuffer *imported_buffer;
+@@ -587,7 +582,7 @@ import_shared_framebuffer (CoglOnscreen                        *onscreen,
+   render_device = secondary_gpu_state->renderer_gpu_data->render_device;
+   imported_buffer =
+     meta_render_device_import_dma_buf (render_device,
+-                                       onscreen_native->gbm.next_fb,
++                                       primary_gpu_fb,
+                                        &error);
+   if (!imported_buffer)
+     {
+@@ -601,16 +596,9 @@ import_shared_framebuffer (CoglOnscreen                        *onscreen,
+                       META_SHARED_FRAMEBUFFER_IMPORT_STATUS_NONE);
+       secondary_gpu_state->import_status =
+         META_SHARED_FRAMEBUFFER_IMPORT_STATUS_FAILED;
+-      return FALSE;
++      return NULL;
+     }
+ 
+-  /*
+-   * next_fb may already contain a fallback buffer, so clear it only
+-   * when we are sure to succeed.
+-   */
+-  g_clear_object (&secondary_gpu_state->gbm.next_fb);
+-  secondary_gpu_state->gbm.next_fb = imported_buffer;
+-
+   if (secondary_gpu_state->import_status ==
+       META_SHARED_FRAMEBUFFER_IMPORT_STATUS_NONE)
+     {
+@@ -627,16 +615,16 @@ import_shared_framebuffer (CoglOnscreen                        *onscreen,
+ 
+   secondary_gpu_state->import_status =
+     META_SHARED_FRAMEBUFFER_IMPORT_STATUS_OK;
+-  return TRUE;
++  return imported_buffer;
+ }
+ 
+-static void
++static MetaDrmBuffer *
+ copy_shared_framebuffer_gpu (CoglOnscreen                        *onscreen,
+                              MetaOnscreenNativeSecondaryGpuState *secondary_gpu_state,
+                              MetaRendererNativeGpuData           *renderer_gpu_data,
+-                             gboolean                            *egl_context_changed)
++                             gboolean                            *egl_context_changed,
++                             MetaDrmBuffer                       *primary_gpu_fb)
+ {
+-  MetaOnscreenNative *onscreen_native = META_ONSCREEN_NATIVE (onscreen);
+   MetaRendererNative *renderer_native = renderer_gpu_data->renderer_native;
+   MetaEgl *egl = meta_renderer_native_get_egl (renderer_native);
+   MetaGles3 *gles3 = meta_renderer_native_get_gles3 (renderer_native);
+@@ -652,9 +640,6 @@ copy_shared_framebuffer_gpu (CoglOnscreen                        *onscreen,
+   COGL_TRACE_BEGIN_SCOPED (CopySharedFramebufferSecondaryGpu,
+                            "FB Copy (secondary GPU)");
+ 
+-  g_warn_if_fail (secondary_gpu_state->gbm.next_fb == NULL);
+-  g_clear_object (&secondary_gpu_state->gbm.next_fb);
+-
+   render_device = renderer_gpu_data->render_device;
+   egl_display = meta_render_device_get_egl_display (render_device);
+ 
+@@ -667,13 +652,13 @@ copy_shared_framebuffer_gpu (CoglOnscreen                        *onscreen,
+     {
+       g_warning ("Failed to make current: %s", error->message);
+       g_error_free (error);
+-      return;
++      return NULL;
+     }
+ 
+   *egl_context_changed = TRUE;
+ 
+ 
+-  buffer_gbm = META_DRM_BUFFER_GBM (onscreen_native->gbm.next_fb);
++  buffer_gbm = META_DRM_BUFFER_GBM (primary_gpu_fb);
+   bo = meta_drm_buffer_gbm_get_bo (buffer_gbm);
+   if (!meta_renderer_native_gles3_blit_shared_bo (egl,
+                                                   gles3,
+@@ -685,7 +670,7 @@ copy_shared_framebuffer_gpu (CoglOnscreen                        *onscreen,
+     {
+       g_warning ("Failed to blit shared framebuffer: %s", error->message);
+       g_error_free (error);
+-      return;
++      return NULL;
+     }
+ 
+   if (!meta_egl_swap_buffers (egl,
+@@ -695,7 +680,7 @@ copy_shared_framebuffer_gpu (CoglOnscreen                        *onscreen,
+     {
+       g_warning ("Failed to swap buffers: %s", error->message);
+       g_error_free (error);
+-      return;
++      return NULL;
+     }
+ 
+   use_modifiers = meta_renderer_native_use_modifiers (renderer_native);
+@@ -715,10 +700,10 @@ copy_shared_framebuffer_gpu (CoglOnscreen                        *onscreen,
+       g_warning ("meta_drm_buffer_gbm_new_lock_front failed: %s",
+                  error->message);
+       g_error_free (error);
+-      return;
++      return NULL;
+     }
+ 
+-  secondary_gpu_state->gbm.next_fb = META_DRM_BUFFER (buffer_gbm);
++  return META_DRM_BUFFER (buffer_gbm);
+ }
+ 
+ static MetaDrmBufferDumb *
+@@ -733,7 +718,7 @@ secondary_gpu_get_next_dumb_buffer (MetaOnscreenNativeSecondaryGpuState *seconda
+     return secondary_gpu_state->cpu.dumb_fbs[0];
+ }
+ 
+-static gboolean
++static MetaDrmBuffer *
+ copy_shared_framebuffer_primary_gpu (CoglOnscreen                        *onscreen,
+                                      MetaOnscreenNativeSecondaryGpuState *secondary_gpu_state,
+                                      const int                           *rectangles,
+@@ -761,7 +746,7 @@ copy_shared_framebuffer_primary_gpu (CoglOnscreen                        *onscre
+   primary_gpu_data =
+     meta_renderer_native_get_gpu_data (renderer_native, primary_gpu);
+   if (!primary_gpu_data->secondary.has_EGL_EXT_image_dma_buf_import_modifiers)
+-    return FALSE;
++    return NULL;
+ 
+   buffer_dumb = secondary_gpu_get_next_dumb_buffer (secondary_gpu_state);
+   buffer = META_DRM_BUFFER (buffer_dumb);
+@@ -784,7 +769,7 @@ copy_shared_framebuffer_primary_gpu (CoglOnscreen                        *onscre
+     {
+       meta_topic (META_DEBUG_KMS,
+                   "Failed to create DMA buffer: %s", error->message);
+-      return FALSE;
++      return NULL;
+     }
+ 
+   dmabuf_fb =
+@@ -802,7 +787,7 @@ copy_shared_framebuffer_primary_gpu (CoglOnscreen                        *onscre
+       meta_topic (META_DEBUG_KMS,
+                   "Failed to create DMA buffer for blitting: %s",
+                   error->message);
+-      return FALSE;
++      return NULL;
+     }
+   /* Limit the number of individual copies to 16 */
+ #define MAX_RECTS 16
+@@ -815,7 +800,7 @@ copy_shared_framebuffer_primary_gpu (CoglOnscreen                        *onscre
+                                   &error))
+         {
+           g_object_unref (dmabuf_fb);
+-          return FALSE;
++          return NULL;
+         }
+     }
+   else
+@@ -832,20 +817,19 @@ copy_shared_framebuffer_primary_gpu (CoglOnscreen                        *onscre
+                                       &error))
+             {
+               g_object_unref (dmabuf_fb);
+-              return FALSE;
++              return NULL;
+             }
+         }
+     }
+ 
+   g_object_unref (dmabuf_fb);
+ 
+-  g_set_object (&secondary_gpu_state->gbm.next_fb, buffer);
+   secondary_gpu_state->cpu.current_dumb_fb = buffer_dumb;
+ 
+-  return TRUE;
++  return g_object_ref (buffer);
+ }
+ 
+-static void
++static MetaDrmBuffer *
+ copy_shared_framebuffer_cpu (CoglOnscreen                        *onscreen,
+                              MetaOnscreenNativeSecondaryGpuState *secondary_gpu_state,
+                              MetaRendererNativeGpuData           *renderer_gpu_data)
+@@ -897,17 +881,19 @@ copy_shared_framebuffer_cpu (CoglOnscreen                        *onscreen,
+ 
+   cogl_object_unref (dumb_bitmap);
+ 
+-  g_set_object (&secondary_gpu_state->gbm.next_fb, buffer);
+   secondary_gpu_state->cpu.current_dumb_fb = buffer_dumb;
++
++  return g_object_ref (buffer);
+ }
+ 
+-static void
++static MetaDrmBuffer *
+ update_secondary_gpu_state_pre_swap_buffers (CoglOnscreen *onscreen,
+                                              const int    *rectangles,
+                                              int           n_rectangles)
+ {
+   MetaOnscreenNative *onscreen_native = META_ONSCREEN_NATIVE (onscreen);
+   MetaOnscreenNativeSecondaryGpuState *secondary_gpu_state;
++  MetaDrmBuffer *copy = NULL;
+ 
+   COGL_TRACE_BEGIN_SCOPED (MetaRendererNativeGpuStatePreSwapBuffers,
+                            "Onscreen (secondary gpu pre-swap-buffers)");
+@@ -933,10 +919,11 @@ update_secondary_gpu_state_pre_swap_buffers (CoglOnscreen *onscreen,
+           /* prepare fallback */
+           G_GNUC_FALLTHROUGH;
+         case META_SHARED_FRAMEBUFFER_COPY_MODE_PRIMARY:
+-          if (!copy_shared_framebuffer_primary_gpu (onscreen,
+-                                                    secondary_gpu_state,
+-                                                    rectangles,
+-                                                    n_rectangles))
++          copy = copy_shared_framebuffer_primary_gpu (onscreen,
++                                                      secondary_gpu_state,
++                                                      rectangles,
++                                                      n_rectangles);
++          if (!copy)
+             {
+               if (!secondary_gpu_state->noted_primary_gpu_copy_failed)
+                 {
+@@ -946,9 +933,9 @@ update_secondary_gpu_state_pre_swap_buffers (CoglOnscreen *onscreen,
+                   secondary_gpu_state->noted_primary_gpu_copy_failed = TRUE;
+                 }
+ 
+-              copy_shared_framebuffer_cpu (onscreen,
+-                                           secondary_gpu_state,
+-                                           renderer_gpu_data);
++              copy = copy_shared_framebuffer_cpu (onscreen,
++                                                  secondary_gpu_state,
++                                                  renderer_gpu_data);
+             }
+           else if (!secondary_gpu_state->noted_primary_gpu_copy_ok)
+             {
+@@ -960,11 +947,15 @@ update_secondary_gpu_state_pre_swap_buffers (CoglOnscreen *onscreen,
+           break;
+         }
+     }
++
++  return copy;
+ }
+ 
+ static void
+-update_secondary_gpu_state_post_swap_buffers (CoglOnscreen *onscreen,
+-                                              gboolean     *egl_context_changed)
++update_secondary_gpu_state_post_swap_buffers (CoglOnscreen   *onscreen,
++                                              gboolean       *egl_context_changed,
++                                              MetaDrmBuffer  *primary_gpu_fb,
++                                              MetaDrmBuffer **secondary_gpu_fb)
+ {
+   MetaOnscreenNative *onscreen_native = META_ONSCREEN_NATIVE (onscreen);
+   MetaRendererNative *renderer_native = onscreen_native->renderer_native;
+@@ -977,6 +968,7 @@ update_secondary_gpu_state_post_swap_buffers (CoglOnscreen *onscreen,
+   if (secondary_gpu_state)
+     {
+       MetaRendererNativeGpuData *renderer_gpu_data;
++      g_autoptr (MetaDrmBuffer) next_fb = NULL;
+ 
+       renderer_gpu_data =
+         meta_renderer_native_get_gpu_data (renderer_native,
+@@ -984,23 +976,30 @@ update_secondary_gpu_state_post_swap_buffers (CoglOnscreen *onscreen,
+       switch (renderer_gpu_data->secondary.copy_mode)
+         {
+         case META_SHARED_FRAMEBUFFER_COPY_MODE_ZERO:
+-          if (import_shared_framebuffer (onscreen, secondary_gpu_state))
++          next_fb = import_shared_framebuffer (onscreen,
++                                               secondary_gpu_state,
++                                               primary_gpu_fb);
++          if (next_fb)
+             break;
+-
+-          /* The fallback was prepared in pre_swap_buffers */
++          /* The fallback was prepared in pre_swap_buffers and is currently
++           * in secondary_gpu_fb.
++           */
+           renderer_gpu_data->secondary.copy_mode =
+             META_SHARED_FRAMEBUFFER_COPY_MODE_PRIMARY;
+           G_GNUC_FALLTHROUGH;
+         case META_SHARED_FRAMEBUFFER_COPY_MODE_PRIMARY:
+-          /* Done before eglSwapBuffers. */
++          next_fb = g_object_ref (*secondary_gpu_fb);
+           break;
+         case META_SHARED_FRAMEBUFFER_COPY_MODE_SECONDARY_GPU:
+-          copy_shared_framebuffer_gpu (onscreen,
+-                                       secondary_gpu_state,
+-                                       renderer_gpu_data,
+-                                       egl_context_changed);
++          next_fb = copy_shared_framebuffer_gpu (onscreen,
++                                                 secondary_gpu_state,
++                                                 renderer_gpu_data,
++                                                 egl_context_changed,
++                                                 primary_gpu_fb);
+           break;
+         }
++
++      g_set_object (secondary_gpu_fb, next_fb);
+     }
+ }
+ 
+@@ -1034,34 +1033,39 @@ meta_onscreen_native_swap_buffers_with_damage (CoglOnscreen  *onscreen,
    CoglRendererEGL *cogl_renderer_egl = cogl_renderer->winsys;
    MetaRendererNativeGpuData *renderer_gpu_data = cogl_renderer_egl->platform;
    MetaRendererNative *renderer_native = renderer_gpu_data->renderer_native;
@@ -1161,33 +2032,121 @@ index 00b2d9f89..eb1e7412a 100644
    MetaOnscreenNative *onscreen_native = META_ONSCREEN_NATIVE (onscreen);
    MetaGpuKms *render_gpu = onscreen_native->render_gpu;
    MetaDeviceFile *render_device_file;
-@@ -1017,14 +989,9 @@ meta_onscreen_native_swap_buffers_with_damage (CoglOnscreen  *onscreen,
+   ClutterFrame *frame = user_data;
    CoglOnscreenClass *parent_class;
    gboolean egl_context_changed = FALSE;
-   gboolean use_modifiers;
 -  MetaPowerSave power_save_mode;
    g_autoptr (GError) error = NULL;
+   MetaDrmBufferFlags buffer_flags;
    MetaDrmBufferGbm *buffer_gbm;
 -  MetaKmsCrtc *kms_crtc;
 -  MetaKmsDevice *kms_device;
 -  MetaKmsUpdateFlag flags;
 -  g_autoptr (MetaKmsFeedback) kms_feedback = NULL;
 -  const GError *feedback_error;
++  g_autoptr (MetaDrmBuffer) primary_gpu_fb = NULL;
++  g_autoptr (MetaDrmBuffer) secondary_gpu_fb = NULL;
 +  size_t rectangles_size;
  
    COGL_TRACE_BEGIN_SCOPED (MetaRendererNativeSwapBuffers,
                             "Onscreen (swap-buffers)");
-@@ -1073,6 +1040,9 @@ meta_onscreen_native_swap_buffers_with_damage (CoglOnscreen  *onscreen,
+ 
+-  update_secondary_gpu_state_pre_swap_buffers (onscreen,
+-                                               rectangles,
+-                                               n_rectangles);
++  if (meta_is_topic_enabled (META_DEBUG_KMS))
++    {
++      unsigned int frames_pending =
++        cogl_onscreen_count_pending_frames (onscreen);
++
++      meta_topic (META_DEBUG_KMS,
++                  "Swap buffers: %u frames pending (%s-buffering)",
++                  frames_pending,
++                  frames_pending == 1 ? "double" :
++                  frames_pending == 2 ? "triple" :
++                  "?");
++    }
++
++  secondary_gpu_fb =
++    update_secondary_gpu_state_pre_swap_buffers (onscreen,
++                                                 rectangles,
++                                                 n_rectangles);
+ 
+   parent_class = COGL_ONSCREEN_CLASS (meta_onscreen_native_parent_class);
+   parent_class->swap_buffers_with_damage (onscreen,
+@@ -1077,9 +1081,6 @@ meta_onscreen_native_swap_buffers_with_damage (CoglOnscreen  *onscreen,
+   switch (renderer_gpu_data->mode)
+     {
+     case META_RENDERER_NATIVE_MODE_GBM:
+-      g_warn_if_fail (onscreen_native->gbm.next_fb == NULL);
+-      g_clear_object (&onscreen_native->gbm.next_fb);
+-
+       buffer_flags = META_DRM_BUFFER_FLAG_NONE;
+       if (!meta_renderer_native_use_modifiers (renderer_native))
+         buffer_flags |= META_DRM_BUFFER_FLAG_DISABLE_MODIFIERS;
+@@ -1097,7 +1098,12 @@ meta_onscreen_native_swap_buffers_with_damage (CoglOnscreen  *onscreen,
+           return;
+         }
+ 
+-      onscreen_native->gbm.next_fb = META_DRM_BUFFER (buffer_gbm);
++      primary_gpu_fb = META_DRM_BUFFER (g_steal_pointer (&buffer_gbm));
++
++      g_object_set_data_full (G_OBJECT (primary_gpu_fb),
++                              "gbm_surface owner",
++                              g_object_ref (onscreen),
++                              (GDestroyNotify) g_object_unref);
+ 
+       break;
+     case META_RENDERER_NATIVE_MODE_SURFACELESS:
+@@ -1109,7 +1115,46 @@ meta_onscreen_native_swap_buffers_with_damage (CoglOnscreen  *onscreen,
  #endif
      }
  
+-  update_secondary_gpu_state_post_swap_buffers (onscreen, &egl_context_changed);
++  update_secondary_gpu_state_post_swap_buffers (onscreen,
++                                                &egl_context_changed,
++                                                primary_gpu_fb,
++                                                &secondary_gpu_fb);
++
++  switch (renderer_gpu_data->mode)
++    {
++    case META_RENDERER_NATIVE_MODE_GBM:
++      if (onscreen_native->gbm.next_fb != NULL)
++        {
++          g_warn_if_fail (onscreen_native->gbm.stalled_fb == NULL);
++          drop_stalled_swap (onscreen);
++          g_assert (onscreen_native->gbm.stalled_fb == NULL);
++          onscreen_native->gbm.stalled_fb =
++            g_steal_pointer (&onscreen_native->gbm.next_fb);
++        }
++
++      if (onscreen_native->secondary_gpu_state)
++        {
++          g_set_object (&onscreen_native->gbm.next_fb, secondary_gpu_fb);
++          hold_primary_gpu_fb_for_secondary_gpu_scanout (
++            onscreen_native->secondary_gpu_state,
++            primary_gpu_fb,
++            secondary_gpu_fb);
++        }
++      else
++        {
++          g_set_object (&onscreen_native->gbm.next_fb, primary_gpu_fb);
++        }
++      break;
++    case META_RENDERER_NATIVE_MODE_SURFACELESS:
++      break;
++#ifdef HAVE_EGL_DEVICE
++    case META_RENDERER_NATIVE_MODE_EGL_DEVICE:
++      break;
++#endif
++    }
++
 +  clutter_frame_set_result (frame,
 +                            CLUTTER_FRAME_RESULT_PENDING_PRESENTED);
-+
-   update_secondary_gpu_state_post_swap_buffers (onscreen, &egl_context_changed);
  
    /*
-@@ -1084,6 +1054,48 @@ meta_onscreen_native_swap_buffers_with_damage (CoglOnscreen  *onscreen,
+    * If we changed EGL context, cogl will have the wrong idea about what is
+@@ -1120,23 +1165,71 @@ meta_onscreen_native_swap_buffers_with_damage (CoglOnscreen  *onscreen,
    if (egl_context_changed)
      _cogl_winsys_egl_ensure_current (cogl_display);
  
@@ -1198,14 +2157,11 @@ index 00b2d9f89..eb1e7412a 100644
 +  onscreen_native->next_post.n_rectangles = n_rectangles;
 +
 +  onscreen_native->swaps_pending++;
-+
-+  /* The new frame is already counted by cogl so that's why it is "<=" */
-+  if (cogl_onscreen_count_pending_frames (onscreen) <= MAX_CONCURRENT_POSTS)
-+    post_latest_swap (onscreen);
++  try_post_latest_swap (onscreen);
 +}
 +
 +static void
-+post_latest_swap (CoglOnscreen *onscreen)
++try_post_latest_swap (CoglOnscreen *onscreen)
 +{
 +  CoglFramebuffer *framebuffer = COGL_FRAMEBUFFER (onscreen);
 +  CoglContext *cogl_context = cogl_framebuffer_get_context (framebuffer);
@@ -1227,16 +2183,28 @@ index 00b2d9f89..eb1e7412a 100644
 +  MetaKmsUpdateFlag flags;
 +  g_autoptr (MetaKmsFeedback) kms_feedback = NULL;
 +  const GError *feedback_error;
++  unsigned int frames_pending = cogl_onscreen_count_pending_frames (onscreen);
 +
 +  if (onscreen_native->swaps_pending == 0)
 +    return;
 +
-+  onscreen_native->swaps_pending--;
++  g_assert (frames_pending >= onscreen_native->swaps_pending);
 +
    power_save_mode = meta_monitor_manager_get_power_save_mode (monitor_manager);
    if (power_save_mode == META_POWER_SAVE_ON)
      {
-@@ -1092,15 +1104,13 @@ meta_onscreen_native_swap_buffers_with_damage (CoglOnscreen  *onscreen,
++      unsigned int posts_pending;
++
++      posts_pending = frames_pending - onscreen_native->swaps_pending;
++      if (posts_pending > 0)
++        return;  /* wait for the next frame notification and then try again */
++
++      drop_stalled_swap (onscreen);
++      g_return_if_fail (onscreen_native->swaps_pending > 0);
++      onscreen_native->swaps_pending--;
++
+       ensure_crtc_modes (onscreen);
+       meta_onscreen_native_flip_crtc (onscreen,
                                        onscreen_native->view,
                                        onscreen_native->crtc,
                                        META_KMS_PAGE_FLIP_LISTENER_FLAG_NONE,
@@ -1254,7 +2222,7 @@ index 00b2d9f89..eb1e7412a 100644
        return;
      }
  
-@@ -1118,9 +1128,6 @@ meta_onscreen_native_swap_buffers_with_damage (CoglOnscreen  *onscreen,
+@@ -1154,9 +1247,6 @@ meta_onscreen_native_swap_buffers_with_damage (CoglOnscreen  *onscreen,
                        "Postponing primary plane composite update for CRTC %u (%s)",
                        meta_kms_crtc_get_id (kms_crtc),
                        meta_kms_device_get_path (kms_device));
@@ -1264,7 +2232,7 @@ index 00b2d9f89..eb1e7412a 100644
            return;
          }
        else if (meta_renderer_native_has_pending_mode_set (renderer_native))
-@@ -1130,8 +1137,6 @@ meta_onscreen_native_swap_buffers_with_damage (CoglOnscreen  *onscreen,
+@@ -1166,8 +1256,6 @@ meta_onscreen_native_swap_buffers_with_damage (CoglOnscreen  *onscreen,
  
            meta_renderer_native_notify_mode_sets_reset (renderer_native);
            meta_renderer_native_post_mode_set_updates (renderer_native);
@@ -1273,7 +2241,7 @@ index 00b2d9f89..eb1e7412a 100644
            return;
          }
        break;
-@@ -1144,8 +1149,6 @@ meta_onscreen_native_swap_buffers_with_damage (CoglOnscreen  *onscreen,
+@@ -1180,8 +1268,6 @@ meta_onscreen_native_swap_buffers_with_damage (CoglOnscreen  *onscreen,
          {
            meta_renderer_native_notify_mode_sets_reset (renderer_native);
            meta_renderer_native_post_mode_set_updates (renderer_native);
@@ -1282,10 +2250,14 @@ index 00b2d9f89..eb1e7412a 100644
            return;
          }
        break;
-@@ -1159,17 +1162,13 @@ meta_onscreen_native_swap_buffers_with_damage (CoglOnscreen  *onscreen,
+@@ -1194,18 +1280,16 @@ meta_onscreen_native_swap_buffers_with_damage (CoglOnscreen  *onscreen,
+               meta_kms_device_get_path (kms_device));
  
    flags = META_KMS_UPDATE_FLAG_NONE;
-   kms_feedback = meta_kms_post_pending_update_sync (kms, kms_device, flags);
+-  kms_feedback = meta_kms_post_pending_update_sync (kms, kms_device, flags);
++  kms_feedback = meta_kms_post_pending_update_for_crtc_sync (kms,
++                                                             kms_crtc,
++                                                             flags);
 +  g_return_if_fail (kms_feedback != NULL);
  
    switch (meta_kms_feedback_get_result (kms_feedback))
@@ -1301,48 +2273,14 @@ index 00b2d9f89..eb1e7412a 100644
        feedback_error = meta_kms_feedback_get_error (kms_feedback);
        if (!g_error_matches (feedback_error,
                              G_IO_ERROR,
-@@ -1187,8 +1186,6 @@ meta_onscreen_native_is_buffer_scanout_compatible (CoglOnscreen *onscreen,
- {
-   MetaOnscreenNative *onscreen_native = META_ONSCREEN_NATIVE (onscreen);
-   const MetaCrtcConfig *crtc_config;
--  MetaDrmBuffer *fb;
--  struct gbm_bo *gbm_bo;
- 
-   crtc_config = meta_crtc_get_config (onscreen_native->crtc);
-   if (crtc_config->transform != META_MONITOR_TRANSFORM_NORMAL)
-@@ -1200,23 +1197,13 @@ meta_onscreen_native_is_buffer_scanout_compatible (CoglOnscreen *onscreen,
-   if (!onscreen_native->gbm.surface)
-     return FALSE;
- 
--  fb = onscreen_native->gbm.current_fb ? onscreen_native->gbm.current_fb
--                                       : onscreen_native->gbm.next_fb;
--  if (!fb)
-+  if (drm_format != onscreen_native->gbm.last_flip.format)
-     return FALSE;
- 
--  if (!META_IS_DRM_BUFFER_GBM (fb))
-+  if (drm_modifier != onscreen_native->gbm.last_flip.modifier)
-     return FALSE;
- 
--  gbm_bo = meta_drm_buffer_gbm_get_bo (META_DRM_BUFFER_GBM (fb));
--
--  if (gbm_bo_get_format (gbm_bo) != drm_format)
--    return FALSE;
--
--  if (gbm_bo_get_modifier (gbm_bo) != drm_modifier)
--    return FALSE;
--
--  if (gbm_bo_get_stride (gbm_bo) != stride)
-+  if (stride != onscreen_native->gbm.last_flip.stride)
-     return FALSE;
- 
-   return TRUE;
-@@ -1272,6 +1259,16 @@ meta_onscreen_native_direct_scanout (CoglOnscreen   *onscreen,
+@@ -1292,6 +1376,18 @@ meta_onscreen_native_direct_scanout (CoglOnscreen   *onscreen,
        return FALSE;
      }
  
-+  /* The new frame is already counted by cogl so that's why it is ">" */
-+  if (cogl_onscreen_count_pending_frames (onscreen) > MAX_CONCURRENT_POSTS)
++  /* Our direct scanout frame counts as 1, so more than that means we would
++   * be jumping the queue (and post would fail).
++   */
++  if (cogl_onscreen_count_pending_frames (onscreen) > 1)
 +    {
 +      g_set_error_literal (error,
 +                           COGL_SCANOUT_ERROR,
@@ -1354,7 +2292,18 @@ index 00b2d9f89..eb1e7412a 100644
    renderer_gpu_data = meta_renderer_native_get_gpu_data (renderer_native,
                                                           render_gpu);
  
-@@ -1338,7 +1335,6 @@ meta_onscreen_native_direct_scanout (CoglOnscreen   *onscreen,
+@@ -1344,7 +1440,9 @@ meta_onscreen_native_direct_scanout (CoglOnscreen   *onscreen,
+               meta_kms_device_get_path (kms_device));
+ 
+   flags = META_KMS_UPDATE_FLAG_PRESERVE_ON_ERROR;
+-  kms_feedback = meta_kms_post_pending_update_sync (kms, kms_device, flags);
++  kms_feedback = meta_kms_post_pending_update_for_crtc_sync (kms,
++                                                             kms_crtc,
++                                                             flags);
+   switch (meta_kms_feedback_get_result (kms_feedback))
+     {
+     case META_KMS_FEEDBACK_PASSED:
+@@ -1358,7 +1456,6 @@ meta_onscreen_native_direct_scanout (CoglOnscreen   *onscreen,
                             G_IO_ERROR, G_IO_ERROR_PERMISSION_DENIED))
          break;
  
@@ -1362,17 +2311,94 @@ index 00b2d9f89..eb1e7412a 100644
        g_propagate_error (error, g_error_copy (feedback_error));
        return FALSE;
      }
-@@ -1374,6 +1370,9 @@ meta_onscreen_native_finish_frame (CoglOnscreen *onscreen,
+@@ -1394,7 +1491,10 @@ meta_onscreen_native_finish_frame (CoglOnscreen *onscreen,
    g_autoptr (MetaKmsFeedback) kms_feedback = NULL;
    const GError *error;
  
-+  if (cogl_onscreen_count_pending_frames (onscreen) >= MAX_CONCURRENT_POSTS)
+-  kms_update = meta_kms_get_pending_update (kms, kms_device);
++  if (cogl_onscreen_count_pending_frames (onscreen) > 0)
 +    return;
 +
-   kms_update = meta_kms_get_pending_update (kms, kms_device);
++  kms_update = meta_kms_get_pending_update_for_crtc (kms, kms_crtc);
    if (!kms_update)
      {
-@@ -2096,7 +2094,6 @@ meta_onscreen_native_dispose (GObject *object)
+       clutter_frame_set_result (frame, CLUTTER_FRAME_RESULT_IDLE);
+@@ -1409,9 +1509,9 @@ meta_onscreen_native_finish_frame (CoglOnscreen *onscreen,
+                                           g_object_unref);
+ 
+   flags = META_KMS_UPDATE_FLAG_NONE;
+-  kms_feedback = meta_kms_post_pending_update_sync (kms,
+-                                                    kms_device,
+-                                                    flags);
++  kms_feedback = meta_kms_post_pending_update_for_crtc_sync (kms,
++                                                             kms_crtc,
++                                                             flags);
+   switch (meta_kms_feedback_get_result (kms_feedback))
+     {
+     case META_KMS_FEEDBACK_PASSED:
+@@ -1433,6 +1533,17 @@ meta_onscreen_native_finish_frame (CoglOnscreen *onscreen,
+     }
+ }
+ 
++void
++meta_onscreen_native_discard_pending_swaps (CoglOnscreen *onscreen)
++{
++  MetaOnscreenNative *onscreen_native = META_ONSCREEN_NATIVE (onscreen);
++
++  onscreen_native->swaps_pending = 0;
++
++  g_clear_object (&onscreen_native->gbm.stalled_fb);
++  g_clear_object (&onscreen_native->gbm.next_fb);
++}
++
+ static gboolean
+ should_surface_be_sharable (CoglOnscreen *onscreen)
+ {
+@@ -1981,6 +2092,21 @@ pick_secondary_gpu_framebuffer_format_for_cpu (CoglOnscreen *onscreen)
+   return DRM_FORMAT_INVALID;
+ }
+ 
++static void
++dumb_toggle_notify (gpointer  data,
++                    GObject  *object,
++                    gboolean  is_last_ref)
++{
++  MetaDrmBuffer **source_fb = data;
++
++  g_return_if_fail (source_fb != NULL);
++  if (is_last_ref && *source_fb)
++    {
++      g_return_if_fail (META_IS_DRM_BUFFER (*source_fb));
++      g_clear_object (source_fb);
++    }
++}
++
+ static gboolean
+ init_secondary_gpu_state_cpu_copy_mode (MetaRendererNative         *renderer_native,
+                                         CoglOnscreen               *onscreen,
+@@ -2037,6 +2163,12 @@ init_secondary_gpu_state_cpu_copy_mode (MetaRendererNative         *renderer_nat
+         }
+ 
+       secondary_gpu_state->cpu.dumb_fbs[i] = META_DRM_BUFFER_DUMB (dumb_buffer);
++      g_object_add_toggle_ref (G_OBJECT (dumb_buffer),
++                               dumb_toggle_notify,
++                               &secondary_gpu_state->cpu.source_fbs[i]);
++
++      /* It was incremented higher than we need by add_toggle_ref */
++      g_object_unref (dumb_buffer);
+     }
+ 
+   /*
+@@ -2116,7 +2248,7 @@ meta_onscreen_native_new (MetaRendererNative *renderer_native,
+   onscreen_native->renderer_native = renderer_native;
+   onscreen_native->render_gpu = render_gpu;
+   onscreen_native->output = output;
+-  onscreen_native->crtc = crtc;
++  onscreen_native->crtc = g_object_ref (crtc);
+ 
+   return onscreen_native;
+ }
+@@ -2137,7 +2269,6 @@ meta_onscreen_native_dispose (GObject *object)
      {
      case META_RENDERER_NATIVE_MODE_GBM:
        g_clear_object (&onscreen_native->gbm.next_fb);
@@ -1380,7 +2406,11 @@ index 00b2d9f89..eb1e7412a 100644
        break;
      case META_RENDERER_NATIVE_MODE_SURFACELESS:
        g_assert_not_reached ();
-@@ -2127,6 +2124,8 @@ meta_onscreen_native_dispose (GObject *object)
+@@ -2165,9 +2296,12 @@ meta_onscreen_native_dispose (GObject *object)
+ 
+   G_OBJECT_CLASS (meta_onscreen_native_parent_class)->dispose (object);
+ 
++  g_clear_object (&onscreen_native->crtc);
    g_clear_pointer (&onscreen_native->gbm.surface, gbm_surface_destroy);
    g_clear_pointer (&onscreen_native->secondary_gpu_state,
                     secondary_gpu_state_free);
@@ -1389,3 +2419,86 @@ index 00b2d9f89..eb1e7412a 100644
  }
  
  static void
+diff --git a/src/backends/native/meta-onscreen-native.h b/src/backends/native/meta-onscreen-native.h
+index 3a85ace26..676c4c445 100644
+--- a/src/backends/native/meta-onscreen-native.h
++++ b/src/backends/native/meta-onscreen-native.h
+@@ -40,6 +40,8 @@ void meta_onscreen_native_finish_frame (CoglOnscreen *onscreen,
+ 
+ void meta_onscreen_native_dummy_power_save_page_flip (CoglOnscreen *onscreen);
+ 
++void meta_onscreen_native_discard_pending_swaps (CoglOnscreen *onscreen);
++
+ gboolean meta_onscreen_native_is_buffer_scanout_compatible (CoglOnscreen  *onscreen,
+                                                             MetaDrmBuffer *fb);
+ 
+diff --git a/src/backends/native/meta-renderer-native.c b/src/backends/native/meta-renderer-native.c
+index 41bf04d66..58e6339a8 100644
+--- a/src/backends/native/meta-renderer-native.c
++++ b/src/backends/native/meta-renderer-native.c
+@@ -661,12 +661,18 @@ static gboolean
+ dummy_power_save_page_flip_cb (gpointer user_data)
+ {
+   MetaRendererNative *renderer_native = user_data;
++  GList *old_list =
++    g_steal_pointer (&renderer_native->power_save_page_flip_onscreens);
+ 
+-  g_list_foreach (renderer_native->power_save_page_flip_onscreens,
++  g_list_foreach (old_list,
+                   (GFunc) meta_onscreen_native_dummy_power_save_page_flip,
+                   NULL);
+-  g_clear_list (&renderer_native->power_save_page_flip_onscreens,
++  g_clear_list (&old_list,
+                 g_object_unref);
++
++  if (renderer_native->power_save_page_flip_onscreens != NULL)
++    return G_SOURCE_CONTINUE;
++
+   renderer_native->power_save_page_flip_source_id = 0;
+ 
+   return G_SOURCE_REMOVE;
+@@ -678,6 +684,9 @@ meta_renderer_native_queue_power_save_page_flip (MetaRendererNative *renderer_na
+ {
+   const unsigned int timeout_ms = 100;
+ 
++  if (g_list_find (renderer_native->power_save_page_flip_onscreens, onscreen))
++    return;
++
+   if (!renderer_native->power_save_page_flip_source_id)
+     {
+       renderer_native->power_save_page_flip_source_id =
+@@ -1386,6 +1395,26 @@ meta_renderer_native_create_view (MetaRenderer       *renderer,
+   return view;
+ }
+ 
++static void
++discard_pending_swaps (MetaRenderer *renderer)
++{
++  GList *views = meta_renderer_get_views (renderer);;
++  GList *l;
++
++  for (l = views; l; l = l->next)
++    {
++      ClutterStageView *stage_view = l->data;
++      CoglFramebuffer *fb = clutter_stage_view_get_onscreen (stage_view);
++      CoglOnscreen *onscreen;
++
++      if (!COGL_IS_ONSCREEN (fb))
++        continue;
++
++      onscreen = COGL_ONSCREEN (fb);
++      meta_onscreen_native_discard_pending_swaps (onscreen);
++    }
++}
++
+ static void
+ keep_current_onscreens_alive (MetaRenderer *renderer)
+ {
+@@ -1414,6 +1443,7 @@ meta_renderer_native_rebuild_views (MetaRenderer *renderer)
+   MetaRendererClass *parent_renderer_class =
+     META_RENDERER_CLASS (meta_renderer_native_parent_class);
+ 
++  discard_pending_swaps (renderer);
+   meta_kms_discard_pending_page_flips (kms);
+   meta_kms_discard_pending_updates (kms);
+