From 0d7b4187daadc6c0bd4d40d5517853ef1b002af7 Mon Sep 17 00:00:00 2001
From: Claude <noreply@anthropic.com>
Date: Thu, 6 Aug 2026 09:17:26 +0000
Subject: [PATCH] Fix login freeze: make the UPower proxy lookup async, not
 blocking
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_connectPowerWatches() used Gio.DBusProxy.new_for_bus_sync(), which
blocks gnome-shell's single main thread until the system bus replies.
Since gnome-shell is the Wayland compositor, that stalls the entire
screen for however long it takes — and this runs every time live
wallpaper starts, including automatically at login whenever it was
left enabled. Right after login, with upowerd/D-Bus still warming up
alongside everything else, that block can run for many seconds up to
the ~25s GDBus timeout, which matches reports of the whole system
freezing right after the greeter/login. Switched to the async
new_for_bus(), guarded by a generation counter so a stale in-flight
lookup can't clobber state from a later _stop()/_connectPowerWatches().
---
 lib/liveWallpaper.js | 37 +++++++++++++++++++++++++++----------
 1 file changed, 27 insertions(+), 10 deletions(-)

diff --git a/lib/liveWallpaper.js b/lib/liveWallpaper.js
index 342cf4d..36cf6e5 100644
--- a/lib/liveWallpaper.js
+++ b/lib/liveWallpaper.js
@@ -7,6 +7,8 @@ import * as Main from 'resource:///org/gnome/shell/ui/main.js';
 import {SettingsKey} from './settingsKeys.js';
 import {loadGstreamerModules, GSTREAMER_INSTALL_HINT} from './gstreamerAvailability.js';
 
+Gio._promisify(Gio.DBusProxy, 'new_for_bus', 'new_for_bus_finish');
+
 /**
  * Ways to get a decoded frame onto an actor, tried in order and "pinned"
  * once one works. `new Clutter.Image()` failed with "is not a constructor"
@@ -79,6 +81,7 @@ export class LiveWallpaperManager {
         this._fullscreenChangedId = 0;
         this._upowerProxy = null;
         this._upowerSignalId = 0;
+        this._powerWatchGeneration = 0;
 
         this._frameCount = 0;
         this._pollCount = 0;
@@ -428,19 +431,33 @@ export class LiveWallpaperManager {
             this._logger.debug(`Fullscreen tracking unavailable, pause-when-fullscreen disabled (${e.message ?? e})`);
         }
 
-        try {
-            this._upowerProxy = Gio.DBusProxy.new_for_bus_sync(
-                Gio.BusType.SYSTEM, Gio.DBusProxyFlags.NONE, null,
-                'org.freedesktop.UPower', '/org/freedesktop/UPower', 'org.freedesktop.UPower', null);
-            this._upowerSignalId = this._upowerProxy.connect(
-                'g-properties-changed', () => this._checkBattery());
-            this._checkBattery();
-        } catch (e) {
-            this._logger.debug(`UPower unavailable, pause-on-battery disabled (${e.message ?? e})`);
-        }
+        // Deliberately async: the *_sync() variant blocks gnome-shell's
+        // single main thread (it *is* the compositor) until the system bus
+        // replies, which can take many seconds — or the full ~25s GDBus
+        // timeout — if upowerd is still starting up or the bus is busy,
+        // exactly the conditions right after login. That froze the entire
+        // screen (and could make the session look hung/crashed) since this
+        // runs every time live wallpaper starts, including automatically
+        // at login whenever it was left enabled.
+        const watchGeneration = ++this._powerWatchGeneration;
+        Gio.DBusProxy.new_for_bus(
+            Gio.BusType.SYSTEM, Gio.DBusProxyFlags.NONE, null,
+            'org.freedesktop.UPower', '/org/freedesktop/UPower', 'org.freedesktop.UPower', null)
+            .then(proxy => {
+                if (watchGeneration !== this._powerWatchGeneration)
+                    return; // Superseded by a _stop()/_connectPowerWatches() while this was in flight.
+                this._upowerProxy = proxy;
+                this._upowerSignalId = proxy.connect('g-properties-changed', () => this._checkBattery());
+                this._checkBattery();
+            })
+            .catch(e => {
+                this._logger.debug(`UPower unavailable, pause-on-battery disabled (${e.message ?? e})`);
+            });
     }
 
     _disconnectPowerWatches() {
+        this._powerWatchGeneration++;
+
         if (this._fullscreenChangedId) {
             global.display.disconnect(this._fullscreenChangedId);
             this._fullscreenChangedId = 0;
-- 
2.54.0