diff --git a/reactos/ntoskrnl/include/internal/kd.h b/reactos/ntoskrnl/include/internal/kd.h
index bc88f5eec03..3002bad4189 100644
--- a/reactos/ntoskrnl/include/internal/kd.h
+++ b/reactos/ntoskrnl/include/internal/kd.h
@@ -342,7 +342,8 @@ typedef enum _KDP_DEBUG_SERVICE
     KdSpare1 = 0x23, /* h */
     KdSpare2 = 0x17, /* i */
     KdSpare3 = 0x24, /* j */
-    EnterDebugger = 0x25  /* k */
+    EnterDebugger = 0x25,  /* k */
+    ThatsWhatSheSaid = 69 /* FIGURE IT OUT */
 } KDP_DEBUG_SERVICE;
 
 /* Dispatch Table for Wrapper Functions */
diff --git a/reactos/ntoskrnl/include/internal/mm.h b/reactos/ntoskrnl/include/internal/mm.h
index c1509c7f848..ada4602f478 100644
--- a/reactos/ntoskrnl/include/internal/mm.h
+++ b/reactos/ntoskrnl/include/internal/mm.h
@@ -293,6 +293,12 @@ typedef struct
     ULONG PagingRequestsInLastFifteenMinutes;
 } MM_STATS;
 
+//
+// These two mappings are actually used by Windows itself, based on the ASSERTS
+//
+#define StartOfAllocation ReadInProgress
+#define EndOfAllocation WriteInProgress
+
 typedef struct _MMPFNENTRY
 {
     USHORT Modified:1;
@@ -1120,6 +1126,12 @@ MmInitializePageList(
     VOID
 );
 
+VOID
+NTAPI
+MmDumpPfnDatabase(
+   VOID
+);
+
 PFN_TYPE
 NTAPI
 MmGetContinuousPages(
diff --git a/reactos/ntoskrnl/kd/kdmain.c b/reactos/ntoskrnl/kd/kdmain.c
index 8874d2142c6..a37f4a61ec3 100644
--- a/reactos/ntoskrnl/kd/kdmain.c
+++ b/reactos/ntoskrnl/kd/kdmain.c
@@ -85,6 +85,10 @@ KdpServiceDispatcher(ULONG Service,
                 case EnterDebugger:
                     DbgBreakPoint();
                     break;
+                    
+                case ThatsWhatSheSaid:
+                    MmDumpPfnDatabase();
+                    break;
 
                 default:
                     break;
diff --git a/reactos/ntoskrnl/mm/freelist.c b/reactos/ntoskrnl/mm/freelist.c
index 45f0307c577..020de2cb440 100644
--- a/reactos/ntoskrnl/mm/freelist.c
+++ b/reactos/ntoskrnl/mm/freelist.c
@@ -251,6 +251,94 @@ MmAllocEarlyPage(VOID)
     return Pfn;
 }
 
+VOID
+NTAPI
+MmDumpPfnDatabase(VOID)
+{
+    ULONG i;
+    PPHYSICAL_PAGE Pfn1;
+    PCHAR State = "????", Consumer = "Unknown";
+    KIRQL OldIrql;
+    
+    OldIrql = KfRaiseIrql(HIGH_LEVEL);
+    
+    //
+    // Loop the PFN database
+    //
+    for (i = 0; i <= MmHighestPhysicalPage; i++)
+    {
+        Pfn1 = MiGetPfnEntry(i);
+        
+        //
+        // Get the consumer
+        //
+        switch (Pfn1->Flags.Consumer)
+        {
+            case MC_NPPOOL:
+                
+                Consumer = "Nonpaged Pool";
+                break;
+                
+            case MC_PPOOL:
+                
+                Consumer = "Paged Pool";
+                break;
+                
+            case MC_CACHE:
+                
+                Consumer = "File System Cache";
+                break;
+                
+            case MC_USER:
+                
+                Consumer = "Process Working Set";
+                break;
+                
+            case MC_SYSTEM:
+                
+                Consumer = "System";
+                break;
+        }
+        
+        //
+        // Get the type
+        //
+        switch (Pfn1->Flags.Type)
+        {
+            case MM_PHYSICAL_PAGE_USED:
+                
+                State = "Used";
+                break;
+                
+            case MM_PHYSICAL_PAGE_FREE:
+                
+                State = "Free";
+                Consumer = "Free";
+                break;
+                
+            case MM_PHYSICAL_PAGE_BIOS:
+                
+                State = "BIOS";
+                Consumer = "System Reserved";
+                break;
+        }
+
+        //
+        // Pretty-print the page
+        //
+        DbgPrint("0x%08p:\t%04s\t%20s\t(%02d.%02d.%02d) [%08p])\n",
+                 i << PAGE_SHIFT,
+                 State,
+                 Consumer,
+                 Pfn1->ReferenceCount,
+                 Pfn1->MapCount,
+                 Pfn1->LockCount,
+                 Pfn1->RmapListHead);
+    }
+    
+    KeLowerIrql(OldIrql);
+}
+
 VOID
 NTAPI
 MmInitializePageList(VOID)