From b2682920467c15f9bca516c5b664e52ab0a286ac Mon Sep 17 00:00:00 2001
From: Gliniak <153369+Gliniak@users.noreply.github.com>
Date: Wed, 17 Jun 2026 22:56:54 +0200
Subject: [PATCH] [Kernel] Use single page to store all Vd pointers and structs

This is to prevent some titles from reaching out of memory crash
---
 src/xenia/kernel/xboxkrnl/xboxkrnl_video.cc | 19 ++++++++++---------
 src/xenia/memory.cc                         | 10 ++++++++--
 2 files changed, 18 insertions(+), 11 deletions(-)

diff --git a/src/xenia/kernel/xboxkrnl/xboxkrnl_video.cc b/src/xenia/kernel/xboxkrnl/xboxkrnl_video.cc
index f4da2c288..12835232b 100644
--- a/src/xenia/kernel/xboxkrnl/xboxkrnl_video.cc
+++ b/src/xenia/kernel/xboxkrnl/xboxkrnl_video.cc
@@ -554,35 +554,36 @@ void RegisterVideoExports(xe::cpu::ExportResolver* export_resolver,
                           KernelState* kernel_state) {
   auto memory = kernel_state->memory();
 
+  // Allocate single page that stores all pointers instead of separate pages.
+  const uint32_t baseAllocation =
+      memory->SystemHeapAlloc(40, 32, kSystemHeapPhysical);  // 40 bytes
+
   // VdGlobalDevice (4b)
   // Pointer to a global D3D device. Games only seem to set this, so we don't
   // have to do anything. We may want to read it back later, though.
-  uint32_t pVdGlobalDevice =
-      memory->SystemHeapAlloc(4, 32, kSystemHeapPhysical);
+  const uint32_t pVdGlobalDevice = 0x801E6FC4;
   export_resolver->SetVariableMapping("xboxkrnl.exe", ordinals::VdGlobalDevice,
                                       pVdGlobalDevice);
-  xe::store_and_swap<uint32_t>(memory->TranslateVirtual(pVdGlobalDevice), 0);
+  xe::store_and_swap<uint32_t>(memory->TranslateVirtual(pVdGlobalDevice),
+                               baseAllocation);
 
   // VdGlobalXamDevice (4b)
   // Pointer to the XAM D3D device, which we don't have.
-  uint32_t pVdGlobalXamDevice =
-      memory->SystemHeapAlloc(4, 32, kSystemHeapPhysical);
+  const uint32_t pVdGlobalXamDevice = 0x801E6FC8;
   export_resolver->SetVariableMapping(
       "xboxkrnl.exe", ordinals::VdGlobalXamDevice, pVdGlobalXamDevice);
   xe::store_and_swap<uint32_t>(memory->TranslateVirtual(pVdGlobalXamDevice), 0);
 
   // VdGpuClockInMHz (4b)
   // GPU clock. Xenos is 500MHz. Hope nothing is relying on this timing...
-  uint32_t pVdGpuClockInMHz =
-      memory->SystemHeapAlloc(4, 32, kSystemHeapPhysical);
+  const uint32_t pVdGpuClockInMHz = 0x801D0E94;
   export_resolver->SetVariableMapping("xboxkrnl.exe", ordinals::VdGpuClockInMHz,
                                       pVdGpuClockInMHz);
   xe::store_and_swap<uint32_t>(memory->TranslateVirtual(pVdGpuClockInMHz), 500);
 
   // VdHSIOCalibrationLock (28b)
   // CriticalSection.
-  uint32_t pVdHSIOCalibrationLock =
-      memory->SystemHeapAlloc(28, 32, kSystemHeapPhysical);
+  const uint32_t pVdHSIOCalibrationLock = 0x801D1210;
   export_resolver->SetVariableMapping(
       "xboxkrnl.exe", ordinals::VdHSIOCalibrationLock, pVdHSIOCalibrationLock);
   auto hsio_lock =
diff --git a/src/xenia/memory.cc b/src/xenia/memory.cc
index 22ba66aee..a3485f2c1 100644
--- a/src/xenia/memory.cc
+++ b/src/xenia/memory.cc
@@ -284,10 +284,16 @@ bool Memory::Initialize() {
   heaps_.vA0000000.Alloc(0x340000, 64 * 1024, kMemoryAllocationReserve,
                          kMemoryProtectNoAccess, true, &unk_phys_alloc);
 
-  uint32_t unknown_xex_range;  // Probably hypervisor?
+  // Allocate memory hypervisor and kernel would use
+  uint32_t hypervisor_range;
   heaps_.v80000000.Alloc(0x40000, 4 * 1024, kMemoryAllocationCommit,
                          kMemoryProtectRead | kMemoryProtectWrite, false,
-                         &unknown_xex_range);
+                         &hypervisor_range);
+
+  uint32_t kernel_range;
+  heaps_.v80000000.Alloc(0x1C0000, 4 * 1024, kMemoryAllocationCommit,
+                         kMemoryProtectRead | kMemoryProtectWrite, false,
+                         &kernel_range);
 
   // Value taken from 544307D5. Title explicitly access this address and this is
   // a value underneath it (It's constant between multiple runs)