From 178e69b39b7c7ccc4e3d9f4ea85b2fde15eeac2a Mon Sep 17 00:00:00 2001
From: Xaver Hugl <xaver.hugl@gmail.com>
Date: Sat, 2 Oct 2021 15:23:24 +0200
Subject: [PATCH] platforms/drm: handle hotplugs with disabled outputs better

If the last enabled output gets removed but we have disabled outputs
still connected, enable the first disabled output to prevent a crash.

BUG: 442990
---
 src/plugins/platforms/drm/drm_backend.cpp | 8 ++++++++
 1 file changed, 8 insertions(+)

diff --git a/src/plugins/platforms/drm/drm_backend.cpp b/src/plugins/platforms/drm/drm_backend.cpp
index 372fba22c1..a99b720177 100644
--- a/src/plugins/platforms/drm/drm_backend.cpp
+++ b/src/plugins/platforms/drm/drm_backend.cpp
@@ -332,6 +332,14 @@ void DrmBackend::removeOutput(DrmAbstractOutput *o)
         m_placeHolderOutput->renderLoop()->inhibit();
     }
     if (m_enabledOutputs.contains(o)) {
+        if (m_enabledOutputs.count() == 1) {
+            for (const auto &output : qAsConst(m_outputs)) {
+                if (output != o) {
+                    output->setEnabled(true);
+                    break;
+                }
+            }
+        }
         m_enabledOutputs.removeOne(o);
         Q_EMIT outputDisabled(o);
     }