From eb6cf00c0e6ff6a215614e0a8fa0024855ccdcff Mon Sep 17 00:00:00 2001
From: sin-ack <sin-ack@users.noreply.github.com>
Date: Sat, 31 Jul 2021 16:22:40 +0000
Subject: [PATCH] SystemMonitor: Register ProcessStateModel with ProcessModel
 on construct

Since this was missing, ProcessStateModel never received
model_did_update, and it was possible for the ProcessModel index to go
stale and show another process.

Fixes #9129.
---
 Userland/Applications/SystemMonitor/ProcessStateWidget.cpp | 7 ++++++-
 1 file changed, 6 insertions(+), 1 deletion(-)

diff --git a/Userland/Applications/SystemMonitor/ProcessStateWidget.cpp b/Userland/Applications/SystemMonitor/ProcessStateWidget.cpp
index 2ff01db2ba..145ba2c1c9 100644
--- a/Userland/Applications/SystemMonitor/ProcessStateWidget.cpp
+++ b/Userland/Applications/SystemMonitor/ProcessStateWidget.cpp
@@ -23,9 +23,14 @@ public:
         : m_target(target)
         , m_pid(pid)
     {
+        m_target.register_client(*this);
         refresh();
     }
-    virtual ~ProcessStateModel() override { }
+
+    virtual ~ProcessStateModel() override
+    {
+        m_target.unregister_client(*this);
+    }
 
     virtual int row_count(const GUI::ModelIndex& = GUI::ModelIndex()) const override { return m_target.column_count({}); }
     virtual int column_count(const GUI::ModelIndex& = GUI::ModelIndex()) const override { return 2; }