From 6fb40574c2fad0cea01392ff75fbc15f422fffbc Mon Sep 17 00:00:00 2001
From: Timo Kreuzer <timo.kreuzer@reactos.org>
Date: Thu, 19 Aug 2010 08:50:23 +0000
Subject: [PATCH] [NTOSKRNL] - Implement support for /BURNMEMORY option. -
 Don't stop boot on bad memory type Patch by Jay Smith, modified by Aleksey,
 even more modified by me.

See issue #4957 for more details.

svn path=/trunk/; revision=48565
---
 reactos/ntoskrnl/ex/init.c        | 52 +++++++++++++++++++++++++++----
 reactos/ntoskrnl/mm/ARM3/mminit.c |  3 +-
 2 files changed, 47 insertions(+), 8 deletions(-)

diff --git a/reactos/ntoskrnl/ex/init.c b/reactos/ntoskrnl/ex/init.c
index b44b58976b2..18dd8aa2b10 100644
--- a/reactos/ntoskrnl/ex/init.c
+++ b/reactos/ntoskrnl/ex/init.c
@@ -815,6 +815,51 @@ ExpLoadBootSymbols(IN PLOADER_PARAMETER_BLOCK LoaderBlock)
     }
 }
 
+VOID
+NTAPI
+ExBurnMemory(IN PLOADER_PARAMETER_BLOCK LoaderBlock,
+             IN ULONG PagesToDestroy,
+             IN TYPE_OF_MEMORY MemoryType)
+{
+    PLIST_ENTRY ListEntry;
+    PMEMORY_ALLOCATION_DESCRIPTOR MemDescriptor;
+
+    DPRINT1("Burn RAM amount: %d pages\n", PagesToDestroy);
+
+    /* Loop the memory descriptors, beginning at the end */
+    for (ListEntry = LoaderBlock->MemoryDescriptorListHead.Blink;
+         ListEntry != &LoaderBlock->MemoryDescriptorListHead;
+         ListEntry = ListEntry->Blink)
+    {
+        /* Get the memory descriptor structure */
+        MemDescriptor = CONTAINING_RECORD(ListEntry,
+                                          MEMORY_ALLOCATION_DESCRIPTOR,
+                                          ListEntry);
+
+        /* Is memory free there or is it temporary? */
+        if (MemDescriptor->MemoryType == LoaderFree ||
+            MemDescriptor->MemoryType == LoaderFirmwareTemporary)
+        {
+            /* Check if the descriptor has more pages than we want */
+            if (MemDescriptor->PageCount > PagesToDestroy)
+            {
+                /* Change block's page count, ntoskrnl doesn't care much */
+                MemDescriptor->PageCount -= PagesToDestroy;
+                break;
+            }
+            else
+            {
+                /* Change block type */
+                MemDescriptor->MemoryType = MemoryType;
+                PagesToDestroy -= MemDescriptor->PageCount;
+
+                /* Check if we are done */
+                if (PagesToDestroy == 0) break;
+            }
+        }
+    }
+}
+
 VOID
 NTAPI
 ExpInitializeExecutive(IN ULONG Cpu,
@@ -919,12 +964,7 @@ ExpInitializeExecutive(IN ULONG Cpu,
             {
                 /* Read the number of pages we'll use */
                 PerfMemUsed = atol(PerfMem + 1) * (1024 * 1024 / PAGE_SIZE);
-                if (PerfMem)
-                {
-                    /* FIXME: TODO */
-                    DPRINT1("Burnable memory support not yet present."
-                            "/BURNMEM option ignored.\n");
-                }
+                if (PerfMemUsed) ExBurnMemory(LoaderBlock, PerfMemUsed, LoaderBad);
             }
         }
     }
diff --git a/reactos/ntoskrnl/mm/ARM3/mminit.c b/reactos/ntoskrnl/mm/ARM3/mminit.c
index 9f9f1b4c974..e7bb328d784 100644
--- a/reactos/ntoskrnl/mm/ARM3/mminit.c
+++ b/reactos/ntoskrnl/mm/ARM3/mminit.c
@@ -831,8 +831,7 @@ MiBuildPfnDatabaseFromLoaderBlock(IN PLOADER_PARAMETER_BLOCK LoaderBlock)
             /* Check for bad RAM */
             case LoaderBad:
             
-                DPRINT1("You have damaged RAM modules. Stopping boot\n");
-                while (TRUE);
+                DPRINT1("You either have specified /BURNMEMORY or damaged RAM modules.\n");
                 break;
 
             /* Check for free RAM */