From 62291089fc03c5804d48a43d0545196208495659 Mon Sep 17 00:00:00 2001
From: Mykola Grymalyuk <khronokernel@icloud.com>
Date: Wed, 4 May 2022 14:27:43 -0600
Subject: [PATCH] sys_patch.py: Add better documentation

---
 CHANGELOG.md           |  1 +
 resources/sys_patch.py | 25 +++++++++++++++++++++----
 2 files changed, 22 insertions(+), 4 deletions(-)

diff --git a/CHANGELOG.md b/CHANGELOG.md
index 2c2cb57a7..5688151ff 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,6 +1,7 @@
 # OpenCore Legacy Patcher changelog
 
 ## 0.4.5
+- Refactor Root Patching System
 
 ## 0.4.4
 - Lower SIP requirement for Root Patching
diff --git a/resources/sys_patch.py b/resources/sys_patch.py
index 69c899635..94eebae2e 100644
--- a/resources/sys_patch.py
+++ b/resources/sys_patch.py
@@ -1,9 +1,26 @@
 # Framework for mounting and patching macOS root volume
 # Copyright (C) 2020-2022, Dhinak G, Mykola Grymalyuk
-# Missing Features:
-# - Full System/Library Snapshotting (need to research how Apple achieves this)
-#   - Temporary Work-around: sudo bless --mount /System/Volumes/Update/mnt1 --bootefi --last-sealed-snapshot
-# - Work-around battery throttling on laptops with no battery (IOPlatformPluginFamily.kext/Contents/PlugIns/ACPI_SMC_PlatformPlugin.kext/Contents/Resources/)
+
+# System based off of Apple's Kernel Development Kit (KDK)
+# - https://developer.apple.com/download/all/
+
+# The system relies on mounting the APFS volume as a live read/write volume
+# We perform our required edits, then create a new snapshot for the system boot
+
+# The manual process is as follows:
+#  1. Mount the APFS volume as a read/write volume
+#     'sudo mount -o nobrowse -t apfs  /dev/disk5s5 /System/Volumes/Update/mnt1'
+#  2. Perform edits to the system (ie. create new KernelCollection)
+#     'sudo kmutil install --volume-root /System/Volumes/Update/mnt1/ --update-all'
+#  3. Create a new snapshot for the system boot
+#     'sudo bless --folder /System/Volumes/Update/mnt1/System/Library/CoreServices --bootefi --create-snapshot'
+
+# Additionally Apple's APFS snapshot system supports system rollbacks:
+#   'sudo bless --mount /System/Volumes/Update/mnt1 --bootefi --last-sealed-snapshot'
+# Note: root volume rollbacks are unstable in Big Sur due to quickly discarding the original snapshot
+# - Generally within 2~ boots, the original snapshot is discarded
+# - Monterey always preserves the original snapshot allowing for reliable rollbacks
+
 
 import shutil
 import subprocess