From 80ea0b49d05e91fbfab4cf5905f6a84ae6236351 Mon Sep 17 00:00:00 2001
From: Aiken Harris <harraiken91@gmail.com>
Date: Sat, 7 Feb 2026 00:30:41 +0100
Subject: [PATCH] Fix boot image size alignment calculation

---
 xtoskrnl/mm/mmgr.cc | 9 ++++-----
 1 file changed, 4 insertions(+), 5 deletions(-)

diff --git a/xtoskrnl/mm/mmgr.cc b/xtoskrnl/mm/mmgr.cc
index fc8e633..0823ad4 100644
--- a/xtoskrnl/mm/mmgr.cc
+++ b/xtoskrnl/mm/mmgr.cc
@@ -26,18 +26,17 @@ MM::Manager::ComputeBootImageSize(OUT PPFN_NUMBER BootImageSize)
 {
     PKERNEL_INITIALIZATION_BLOCK InitializationBlock;
     PFN_NUMBER ImageSize;
-    ULONG PteSize;
+    ULONG_PTR Alignment;
 
     /* Get the kernel initialization block */
     InitializationBlock = KE::BootInformation::GetInitializationBlock();
 
-    /* Get the size of a PTE */
-    PteSize = MM::Paging::GetPteSize();
+    /* Calculate the alignment based on the PTE size */
+    Alignment = ((MM_PAGE_SIZE / MM::Paging::GetPteSize()) * MM_PAGE_SIZE);
 
     /* Calculate the size of the boot image */
     ImageSize = InitializationBlock->BootImageSize * MM_PAGE_SIZE;
-    ImageSize = (ImageSize + ((MM_PAGE_SIZE / PteSize) * MM_PAGE_SIZE) - 1) &
-                ~(((MM_PAGE_SIZE / PteSize) * MM_PAGE_SIZE) - 1);
+    ImageSize = (ImageSize + Alignment - 1) & ~(Alignment - 1);
 
     /* Return number of pages used by the boot image */
     *BootImageSize = ImageSize / MM_PAGE_SIZE;