Fix critical memory corruption bug caused by overwriting active page tables marked as free memory

boot/xtldr/arch/amd64/memory.cc

@@ -28,13 +28,12 @@ EFI_STATUS
 Memory::BuildPageMap(IN PXTBL_PAGE_MAPPING PageMap,
                      IN ULONG_PTR SelfMapAddress)
 {
-    PLIST_ENTRY ListEntry, ModulesList, ModulesListEntry;
+    PLIST_ENTRY ModulesList, ModulesListEntry;
-    PXTBL_MEMORY_MAPPING Mapping;
     PXTBL_MODULE_INFO ModuleInfo;
     EFI_PHYSICAL_ADDRESS Address;
-    PVOID LoaderBase;
     ULONGLONG LoaderSize;
     EFI_STATUS Status;
+    PVOID LoaderBase;
 
     /* Allocate pages for the Page Map */
     Status = AllocatePages(AllocateAnyPages, 1, &Address);
@@ -65,7 +64,7 @@ Memory::BuildPageMap(IN PXTBL_PAGE_MAPPING PageMap,
     }
 
     /* Map the trampoline code area */
-    Status = MapVirtualMemory(PageMap, MM_TRAMPOLINE_ADDRESS,MM_TRAMPOLINE_ADDRESS,
+    Status = MapVirtualMemory(PageMap, MM_TRAMPOLINE_ADDRESS, MM_TRAMPOLINE_ADDRESS,
                               1, LoaderFirmwareTemporary);
     if(Status != STATUS_EFI_SUCCESS)
     {
@@ -117,6 +116,28 @@ Memory::BuildPageMap(IN PXTBL_PAGE_MAPPING PageMap,
         return STATUS_EFI_PROTOCOL_ERROR;
     }
 
+    /* Return success */
+    return STATUS_EFI_SUCCESS;
+}
+
+/**
+ * Iterates through the memory map and physically maps all virtual addresses to page tables.
+ *
+ * @param PageMap
+ *        Supplies a pointer to the page mapping structure.
+ *
+ * @return This routine returns a status code.
+ *
+ * @since XT 1.0
+ */
+XTCDECL
+EFI_STATUS
+Memory::CommitPageMap(IN PXTBL_PAGE_MAPPING PageMap)
+{
+    PXTBL_MEMORY_MAPPING Mapping;
+    PLIST_ENTRY ListEntry;
+    EFI_STATUS Status;
+
     /* Iterate through and map all the mappings*/
     Debug::Print(L"Mapping and dumping EFI memory:\n");
     ListEntry = PageMap->MemoryMap.Flink;

boot/xtldr/arch/i686/memory.cc

@@ -25,13 +25,12 @@ EFI_STATUS
 Memory::BuildPageMap(IN PXTBL_PAGE_MAPPING PageMap,
                      IN ULONG_PTR SelfMapAddress)
 {
-    PLIST_ENTRY ListEntry, ModulesList, ModulesListEntry;
     EFI_PHYSICAL_ADDRESS Address, DirectoryAddress;
+    PLIST_ENTRY ModulesList, ModulesListEntry;
     PXTBL_MODULE_INFO ModuleInfo;
-    PXTBL_MEMORY_MAPPING Mapping;
-    PVOID LoaderBase;
     ULONGLONG LoaderSize;
     EFI_STATUS Status;
+    PVOID LoaderBase;
     ULONG Index;
 
     /* Check the page map level to determine which paging structure to create */
@@ -45,6 +44,14 @@ Memory::BuildPageMap(IN PXTBL_PAGE_MAPPING PageMap,
             return Status;
         }
 
+        /* Add new memory mapping for the page map itself */
+        Status = MapVirtualMemory(PageMap, (ULONGLONG)NULLPTR, Address, 1, LoaderMemoryData);
+        if(Status != STATUS_EFI_SUCCESS)
+        {
+            /* Memory mapping failure */
+            return Status;
+        }
+
         /* Assign the allocated page to the page map and zero it out */
         PageMap->PtePointer = (PVOID)(UINT_PTR)Address;
         RTL::Memory::ZeroMemory(PageMap->PtePointer, EFI_PAGE_SIZE);
@@ -57,6 +64,14 @@ Memory::BuildPageMap(IN PXTBL_PAGE_MAPPING PageMap,
             return Status;
         }
 
+        /* Add new memory mapping for the Page Directories (PDs) */
+        Status = MapVirtualMemory(PageMap, (ULONGLONG)NULLPTR, DirectoryAddress, 4, LoaderMemoryData);
+        if(Status != STATUS_EFI_SUCCESS)
+        {
+            /* Memory mapping failure */
+            return Status;
+        }
+
         /* Zero-fill the allocated memory for the Page Directories */
         RTL::Memory::ZeroMemory((PVOID)DirectoryAddress, EFI_PAGE_SIZE * 4);
 
@@ -79,6 +94,14 @@ Memory::BuildPageMap(IN PXTBL_PAGE_MAPPING PageMap,
             return Status;
         }
 
+        /* Add new memory mapping for the page map itself */
+        Status = MapVirtualMemory(PageMap, (ULONGLONG)NULLPTR, Address, 1, LoaderMemoryData);
+        if(Status != STATUS_EFI_SUCCESS)
+        {
+            /* Memory mapping failure */
+            return Status;
+        }
+
         /* Assign the allocated page to the page map and zero it out */
         PageMap->PtePointer = (PVOID)(UINT_PTR)Address;
         RTL::Memory::ZeroMemory(PageMap->PtePointer, EFI_PAGE_SIZE);
@@ -144,6 +167,28 @@ Memory::BuildPageMap(IN PXTBL_PAGE_MAPPING PageMap,
         return STATUS_EFI_PROTOCOL_ERROR;
     }
 
+    /* Return success */
+    return STATUS_EFI_SUCCESS;
+}
+
+/**
+ * Iterates through the memory map and physically maps all virtual addresses to page tables.
+ *
+ * @param PageMap
+ *        Supplies a pointer to the page mapping structure.
+ *
+ * @return This routine returns a status code.
+ *
+ * @since XT 1.0
+ */
+XTCDECL
+EFI_STATUS
+Memory::CommitPageMap(IN PXTBL_PAGE_MAPPING PageMap)
+{
+    PXTBL_MEMORY_MAPPING Mapping;
+    PLIST_ENTRY ListEntry;
+    EFI_STATUS Status;
+
     /* Iterate through and map all the mappings*/
     Debug::Print(L"Mapping and dumping EFI memory:\n");
     ListEntry = PageMap->MemoryMap.Flink;

boot/xtldr/includes/xtldr.hh

@@ -165,6 +165,7 @@ class Memory
                                                OUT PVOID *Memory);
         STATIC XTCDECL EFI_STATUS BuildPageMap(IN PXTBL_PAGE_MAPPING PageMap,
                                                IN ULONG_PTR SelfMapAddress);
+        STATIC XTCDECL EFI_STATUS CommitPageMap(IN PXTBL_PAGE_MAPPING PageMap);
         STATIC XTCDECL EFI_STATUS FreePages(IN ULONGLONG NumberOfPages,
                                             IN EFI_PHYSICAL_ADDRESS Memory);
         STATIC XTCDECL EFI_STATUS FreePool(IN PVOID Memory);

boot/xtldr/modules/xtos_o/amd64/memory.cc

@@ -10,6 +10,34 @@
 #include <xtos.hh>
 
 
+XTCDECL
+EFI_STATUS
+Xtos::BuildPageMap(IN PXTBL_PAGE_MAPPING PageMap)
+{
+    EFI_STATUS Status;
+
+    /* Build page map */
+    Status = XtLdrProtocol->Memory.BuildPageMap(PageMap, (PageMap->PageMapLevel > 4) ? MM_P5E_LA57_BASE : MM_PXE_BASE);
+    if(Status != STATUS_EFI_SUCCESS)
+    {
+        /* Failed to build page map */
+        XtLdrProtocol->Debug.Print(L"Failed to build page map (Status code: %zX)\n", Status);
+        return Status;
+    }
+
+    /* Map memory for hardware layer */
+    Status = MapHardwareMemoryPool(PageMap);
+    if(Status != STATUS_EFI_SUCCESS)
+    {
+        /* Failed to map memory for hardware layer */
+        XtLdrProtocol->Debug.Print(L"Failed to map memory for hardware leyer (Status code: %zX)\n", Status);
+        return Status;
+    }
+
+    /* Return success */
+    return STATUS_EFI_SUCCESS;
+}
+
 /**
  * Determines the appropriate EFI memory mapping strategy for the AMD64 architecture.
  *
@@ -91,24 +119,6 @@ Xtos::EnablePaging(IN PXTBL_PAGE_MAPPING PageMap)
     ULONG_PTR TrampolineSize;
     PVOID TrampolineCode;
 
-    /* Build page map */
-    Status = XtLdrProtocol->Memory.BuildPageMap(PageMap, (PageMap->PageMapLevel > 4) ? MM_P5E_LA57_BASE : MM_PXE_BASE);
-    if(Status != STATUS_EFI_SUCCESS)
-    {
-        /* Failed to build page map */
-        XtLdrProtocol->Debug.Print(L"Failed to build page map (Status code: %zX)\n", Status);
-        return Status;
-    }
-
-    /* Map memory for hardware layer */
-    Status = MapHardwareMemoryPool(PageMap);
-    if(Status != STATUS_EFI_SUCCESS)
-    {
-        /* Failed to map memory for hardware layer */
-        XtLdrProtocol->Debug.Print(L"Failed to map memory for hardware leyer (Status code: %zX)\n", Status);
-        return Status;
-    }
-
     /* Check the configured page map level to set the LA57 state accordingly */
     if(PageMap->PageMapLevel == 5)
     {
@@ -188,6 +198,7 @@ Xtos::MapHardwareMemoryPool(IN PXTBL_PAGE_MAPPING PageMap)
     PHARDWARE_PTE P5eBase, PdeBase, PpeBase, PxeBase;
     EFI_PHYSICAL_ADDRESS Address;
     EFI_STATUS Status;
+    ULONG Index;
 
     if(PageMap->PageMapLevel == 5)
     {
@@ -205,6 +216,9 @@ Xtos::MapHardwareMemoryPool(IN PXTBL_PAGE_MAPPING PageMap)
                 return Status;
             }
 
+            /* Map hardware memory */
+            XtLdrProtocol->Memory.MapVirtualMemory(PageMap, (ULONGLONG)NULLPTR, Address, 1, LoaderMemoryData);
+
             /* Zero fill memory used by P5E */
             XtLdrProtocol->Memory.ZeroMemory((PVOID)Address, EFI_PAGE_SIZE);
 
@@ -239,6 +253,9 @@ Xtos::MapHardwareMemoryPool(IN PXTBL_PAGE_MAPPING PageMap)
             return Status;
         }
 
+        /* Map hardware memory */
+        XtLdrProtocol->Memory.MapVirtualMemory(PageMap, (ULONGLONG)NULLPTR, Address, 1, LoaderMemoryData);
+
         /* Zero fill memory used by PXE */
         XtLdrProtocol->Memory.ZeroMemory((PVOID)Address, EFI_PAGE_SIZE);
 
@@ -267,6 +284,9 @@ Xtos::MapHardwareMemoryPool(IN PXTBL_PAGE_MAPPING PageMap)
             return Status;
         }
 
+        /* Map hardware memory */
+        XtLdrProtocol->Memory.MapVirtualMemory(PageMap, (ULONGLONG)NULLPTR, Address, 1, LoaderMemoryData);
+
         /* Zero fill memory used by PPE */
         XtLdrProtocol->Memory.ZeroMemory((PVOID)Address, EFI_PAGE_SIZE);
 
@@ -285,7 +305,7 @@ Xtos::MapHardwareMemoryPool(IN PXTBL_PAGE_MAPPING PageMap)
     }
 
     /* Loop through 2 PDE entries */
-    for(UINT Index = 0 ; Index < 2 ; Index++)
+    for(Index = 0 ; Index < 2 ; Index++)
     {
         /* Check if PDE entry already exists */
         if(!PdeBase[((MM_HARDWARE_VA_START >> MM_PDI_SHIFT) & 0x1FF) + Index].Valid)
@@ -298,6 +318,9 @@ Xtos::MapHardwareMemoryPool(IN PXTBL_PAGE_MAPPING PageMap)
                 return Status;
             }
 
+            /* Map hardware memory */
+            XtLdrProtocol->Memory.MapVirtualMemory(PageMap, (ULONGLONG)NULLPTR, Address, 1, LoaderMemoryData);
+
             /* Zero fill memory used by PDE */
             XtLdrProtocol->Memory.ZeroMemory((PVOID)Address, EFI_PAGE_SIZE);
 

boot/xtldr/modules/xtos_o/i686/memory.cc

@@ -9,6 +9,47 @@
 #include <xtos.hh>
 
 
+XTCDECL
+EFI_STATUS
+Xtos::BuildPageMap(IN PXTBL_PAGE_MAPPING PageMap)
+{
+    ULONG_PTR SelfMapAddress;
+    EFI_STATUS Status;
+
+    /* Initialize self map address */
+    if(PageMap->PageMapLevel == 3)
+    {
+        /* For PML3 (PAE) use PTE base address */
+        SelfMapAddress = MM_PTE_BASE;
+    }
+    else
+    {
+        /* For PML2 (PAE disabled) use legacy PDE base address */
+        SelfMapAddress = MM_PDE_LEGACY_BASE;
+    }
+
+    /* Build page map */
+    Status = XtLdrProtocol->Memory.BuildPageMap(PageMap, SelfMapAddress);
+    if(Status != STATUS_EFI_SUCCESS)
+    {
+        /* Failed to build page map */
+        XtLdrProtocol->Debug.Print(L"Failed to build page map (Status code: %zX)\n", Status);
+        return Status;
+    }
+
+    /* Map memory for hardware layer */
+    Status = MapHardwareMemoryPool(PageMap);
+    if(Status != STATUS_EFI_SUCCESS)
+    {
+        /* Failed to map memory for hardware layer */
+        XtLdrProtocol->Debug.Print(L"Failed to map memory for hardware layer (Status code: %zX)\n", Status);
+        return Status;
+    }
+
+    /* Return success */
+    return STATUS_EFI_SUCCESS;
+}
+
 /**
  * Determines the appropriate EFI memory mapping strategy for the i686 architecture.
  *
@@ -74,37 +115,6 @@ EFI_STATUS
 Xtos::EnablePaging(IN PXTBL_PAGE_MAPPING PageMap)
 {
     EFI_STATUS Status;
-    ULONG_PTR SelfMapAddress;
-
-    /* Initialize self map address */
-    if(PageMap->PageMapLevel == 3)
-    {
-        /* For PML3 (PAE) use PTE base address */
-        SelfMapAddress = MM_PTE_BASE;
-    }
-    else
-    {
-        /* For PML2 (PAE disabled) use legacy PDE base address */
-        SelfMapAddress = MM_PDE_LEGACY_BASE;
-    }
-
-    /* Build page map */
-    Status = XtLdrProtocol->Memory.BuildPageMap(PageMap, SelfMapAddress);
-    if(Status != STATUS_EFI_SUCCESS)
-    {
-        /* Failed to build page map */
-        XtLdrProtocol->Debug.Print(L"Failed to build page map (Status code: %zX)\n", Status);
-        return Status;
-    }
-
-    /* Map memory for hardware layer */
-    Status = MapHardwareMemoryPool(PageMap);
-    if(Status != STATUS_EFI_SUCCESS)
-    {
-        /* Failed to map memory for hardware layer */
-        XtLdrProtocol->Debug.Print(L"Failed to map memory for hardware layer (Status code: %zX)\n", Status);
-        return Status;
-    }
 
     /* Exit EFI Boot Services */
     XtLdrProtocol->Debug.Print(L"Exiting EFI boot services\n");
@@ -173,6 +183,9 @@ Xtos::MapHardwareMemoryPool(IN PXTBL_PAGE_MAPPING PageMap)
     /* Zero fill allocated memory */
     XtLdrProtocol->Memory.ZeroMemory((PVOID)Address, EFI_PAGE_SIZE);
 
+    /* Map hardware memory */
+    XtLdrProtocol->Memory.MapVirtualMemory(PageMap, (ULONGLONG)NULLPTR, Address, 1, LoaderMemoryData);
+
     /* Check if PAE is enabled (3-level paging) */
     if(PageMap->PageMapLevel == 3)
     {

boot/xtldr/modules/xtos_o/includes/xtos.hh

@@ -38,6 +38,7 @@ class Xtos
                                                           IN PVOID PhysicalAddress,
                                                           IN UINT NumberOfPages,
                                                           IN LOADER_MEMORY_TYPE MemoryType);
+        STATIC XTCDECL EFI_STATUS BuildPageMap(IN PXTBL_PAGE_MAPPING PageMap);
         STATIC XTCDECL LOADER_MEMORY_TYPE ConvertEfiMemoryType(IN EFI_MEMORY_TYPE EfiMemoryType);
         STATIC XTCDECL BOOLEAN DetermineMappingStrategy();
         STATIC XTCDECL ULONG DeterminePagingLevel(IN CONST PWCHAR Parameters);
@@ -47,10 +48,13 @@ class Xtos
                                                   IN PULONG_PTR FrameBufferSize,
                                                   IN PXTBL_FRAMEBUFFER_MODE_INFORMATION FrameBufferModeInfo);
         STATIC XTCDECL EFI_STATUS GetMemoryDescriptorList(IN PXTBL_PAGE_MAPPING PageMap,
-                                                          IN PVOID *VirtualAddress,
+                                                          IN EFI_PHYSICAL_ADDRESS PhysicalBase,
+                                                          IN PVOID VirtualBase,
                                                           OUT PLIST_ENTRY MemoryDescriptorList);
         STATIC XTCDECL EFI_STATUS GetSystemResourcesList(IN PXTBL_PAGE_MAPPING PageMap,
-                                                         IN PVOID *VirtualAddress,
+                                                         IN EFI_PHYSICAL_ADDRESS PhysicalBase,
+                                                         IN PVOID VirtualBase,
+                                                         IN PVOID FrameBufferVirtualBase,
                                                          OUT PLIST_ENTRY SystemResourcesList);
         STATIC XTCDECL EFI_STATUS GetVirtualAddress(IN PLIST_ENTRY MemoryMappings,
                                                     IN PVOID PhysicalAddress,

boot/xtldr/modules/xtos_o/xtos.cc

@@ -191,38 +191,16 @@ Xtos::GetDisplayInformation(OUT PSYSTEM_RESOURCE_FRAMEBUFFER FrameBufferResource
 XTCDECL
 EFI_STATUS
 Xtos::GetMemoryDescriptorList(IN PXTBL_PAGE_MAPPING PageMap,
-                              IN PVOID *VirtualAddress,
+                              IN EFI_PHYSICAL_ADDRESS PhysicalBase,
+                              IN PVOID VirtualBase,
                               OUT PLIST_ENTRY MemoryDescriptorList)
 {
     PLOADER_MEMORY_DESCRIPTOR Descriptor;
     PXTBL_MEMORY_MAPPING MemoryMapping;
-    EFI_PHYSICAL_ADDRESS Address;
     PLIST_ENTRY ListEntry;
-    EFI_STATUS Status;
-    ULONGLONG Pages;
-
-    /* Calculate the number of pages required to store the memory descriptor array */
-    Pages = (ULONGLONG)EFI_SIZE_TO_PAGES((PageMap->MapSize + 1) * sizeof(LOADER_MEMORY_DESCRIPTOR));
-
-    /* Allocate physical pages to hold the memory descriptor list */
-    Status = XtLdrProtocol->Memory.AllocatePages(AllocateAnyPages, Pages, &Address);
-    if(Status != STATUS_EFI_SUCCESS)
-    {
-        /* Page allocation failed, return the status code */
-        return Status;
-    }
-
-    /* Create a virtual memory mapping for the allocated descriptor buffer */
-    Status = XtLdrProtocol->Memory.MapVirtualMemory(PageMap, (ULONGLONG)*VirtualAddress, Address, Pages, LoaderMemoryData);
-    if(Status != STATUS_EFI_SUCCESS)
-    {
-        /* Release the allocated pages as the virtual mapping failed and return status code */
-        XtLdrProtocol->Memory.FreePages(Address, Pages);
-        return Status;
-    }
 
     /* Initialize the descriptor pointer to the start of the allocated physical buffer */
-    Descriptor = (PLOADER_MEMORY_DESCRIPTOR)Address;
+    Descriptor = (PLOADER_MEMORY_DESCRIPTOR)PhysicalBase;
 
     /* Get the first entry from the internal boot loader memory map */
     ListEntry = PageMap->MemoryMap.Flink;
@@ -247,17 +225,18 @@ Xtos::GetMemoryDescriptorList(IN PXTBL_PAGE_MAPPING PageMap,
     }
 
     /* Convert all physical link pointers in the list to their corresponding virtual addresses */
-    XtLdrProtocol->Memory.PhysicalListToVirtual(PageMap, MemoryDescriptorList, (PVOID)Address, *VirtualAddress);
+    XtLdrProtocol->Memory.PhysicalListToVirtual(PageMap, MemoryDescriptorList, (PVOID)PhysicalBase, VirtualBase);
 
-    /* Advance the virtual address pointer to the next available free region and return success */
+    /* Return success */
-    *VirtualAddress = (PUINT8)*VirtualAddress + (Pages * EFI_PAGE_SIZE);
     return STATUS_EFI_SUCCESS;
 }
 
 XTCDECL
 EFI_STATUS
 Xtos::GetSystemResourcesList(IN PXTBL_PAGE_MAPPING PageMap,
-                             IN PVOID *VirtualAddress,
+                             IN EFI_PHYSICAL_ADDRESS PhysicalBase,
+                             IN PVOID VirtualBase,
+                             IN PVOID FrameBufferVirtualBase,
                              OUT PLIST_ENTRY SystemResourcesList)
 {
     XTSTATUS Status;
@@ -268,39 +247,18 @@ Xtos::GetSystemResourcesList(IN PXTBL_PAGE_MAPPING PageMap,
     PXTBL_FRAMEBUFFER_PROTOCOL FrameBufProtocol;
     XTBL_FRAMEBUFFER_MODE_INFORMATION FbModeInfo;
     EFI_PHYSICAL_ADDRESS FbAddress;
+    EFI_PHYSICAL_ADDRESS OriginalPhysicalBase;
     ULONG_PTR FbSize;
-    UINT FrameBufferPages;
     PSYSTEM_RESOURCE_FRAMEBUFFER FrameBufferResource;
     PSYSTEM_RESOURCE_ACPI AcpiResource;
-    ULONGLONG Pages;
-    EFI_PHYSICAL_ADDRESS Address;
-    PVOID PhysicalBase, VirtualBase;
 
-    Pages = (ULONGLONG)EFI_SIZE_TO_PAGES(sizeof(SYSTEM_RESOURCE_ACPI) + sizeof(SYSTEM_RESOURCE_FRAMEBUFFER));
+    /* Save original physical base */
-
+    OriginalPhysicalBase = PhysicalBase;
-    Status = XtLdrProtocol->Memory.AllocatePages(AllocateAnyPages, Pages, &Address);
-    if(Status != STATUS_EFI_SUCCESS)
-    {
-        return Status;
-    }
-    Status = XtLdrProtocol->Memory.MapVirtualMemory(PageMap, (ULONGLONG)*VirtualAddress, Address, Pages, LoaderFirmwarePermanent);
-    if(Status != STATUS_EFI_SUCCESS)
-    {
-        XtLdrProtocol->Memory.FreePages(Address, Pages);
-        return Status;
-    }
-
-    PhysicalBase = (PVOID)Address;
-    VirtualBase = *VirtualAddress;
-
-    /* Calculate next valid virtual address */
-    *VirtualAddress = (PUINT8)*VirtualAddress + (Pages * EFI_PAGE_SIZE);
-
-    AcpiResource = (PSYSTEM_RESOURCE_ACPI)Address;
 
+    AcpiResource = (PSYSTEM_RESOURCE_ACPI)PhysicalBase;
     XtLdrProtocol->Memory.ZeroMemory(AcpiResource, sizeof(SYSTEM_RESOURCE_ACPI));
 
-    /* Load FrameBuffer protocol */
+    /* Load ACPI protocol */
     Status = XtLdrProtocol->Protocol.Open(&ProtocolHandle, (PVOID*)&AcpiProtocol, &AcpiGuid);
     if(Status != STATUS_EFI_SUCCESS)
     {
@@ -319,13 +277,11 @@ Xtos::GetSystemResourcesList(IN PXTBL_PAGE_MAPPING PageMap,
 
     XtLdrProtocol->LinkedList.InsertTail(SystemResourcesList, &AcpiResource->Header.ListEntry);
 
-    /* Close FrameBuffer protocol */
+    /* Close ACPI protocol */
-    XtLdrProtocol->Protocol.Close(&ProtocolHandle, &FrameBufGuid);
+    XtLdrProtocol->Protocol.Close(&ProtocolHandle, &AcpiGuid);
-
-    Address = Address + sizeof(SYSTEM_RESOURCE_ACPI);
-
-    FrameBufferResource = (PSYSTEM_RESOURCE_FRAMEBUFFER)Address;
 
+    PhysicalBase = PhysicalBase + sizeof(SYSTEM_RESOURCE_ACPI);
+    FrameBufferResource = (PSYSTEM_RESOURCE_FRAMEBUFFER)PhysicalBase;
     XtLdrProtocol->Memory.ZeroMemory(FrameBufferResource, sizeof(SYSTEM_RESOURCE_FRAMEBUFFER));
 
     /* Load FrameBuffer protocol */
@@ -346,26 +302,16 @@ Xtos::GetSystemResourcesList(IN PXTBL_PAGE_MAPPING PageMap,
         return Status;
     }
 
-    /* Calculate pages needed to map framebuffer */
+    /* Assign the pre-mapped virtual address to the resource block */
-    FrameBufferPages = EFI_SIZE_TO_PAGES(FbSize);
+    FrameBufferResource->Header.VirtualAddress = FrameBufferVirtualBase;
-
-    /* Rewrite framebuffer address by using virtual address */
-    FrameBufferResource->Header.VirtualAddress = *VirtualAddress;
-
-    /* Map frame buffer memory */
-    XtLdrProtocol->Memory.MapVirtualMemory(PageMap, (ULONGLONG)FrameBufferResource->Header.VirtualAddress,
-                                           (ULONGLONG)FrameBufferResource->Header.PhysicalAddress,
-                                           FrameBufferPages, LoaderFirmwarePermanent);
-
-    /* Close FrameBuffer protocol */
     XtLdrProtocol->Protocol.Close(&ProtocolHandle, &FrameBufGuid);
 
-    *VirtualAddress = (PUINT8)*VirtualAddress + (FrameBufferPages * EFI_PAGE_SIZE);
-
     XtLdrProtocol->LinkedList.InsertTail(SystemResourcesList, &FrameBufferResource->Header.ListEntry);
 
-    XtLdrProtocol->Memory.PhysicalListToVirtual(PageMap, SystemResourcesList, PhysicalBase, VirtualBase);
+    /* Convert list pointers to virtual */
+    XtLdrProtocol->Memory.PhysicalListToVirtual(PageMap, SystemResourcesList, (PVOID)OriginalPhysicalBase, VirtualBase);
 
+    /* Return success */
     return STATUS_EFI_SUCCESS;
 }
 
@@ -426,34 +372,97 @@ Xtos::InitializeApicBase(IN PXTBL_PAGE_MAPPING PageMap)
 XTCDECL
 EFI_STATUS
 Xtos::InitializeLoaderBlock(IN PXTBL_PAGE_MAPPING PageMap,
-                            IN PVOID *VirtualAddress,
+                            IN OUT PVOID *VirtualAddress,
                             IN PXTBL_BOOT_PARAMETERS Parameters)
 {
+    EFI_PHYSICAL_ADDRESS FbPhysicalAddress, PhysicalBlock, PhysicalDescriptor, PhysicalResources;
+    PVOID FbVirtualAddress, VirtualBlock, VirtualResources, VirtualDescriptor;
+    UINT BlockPages, DescriptorPages, FbPages, ParametersSize, ResourcesPages;
+    XTBL_FRAMEBUFFER_MODE_INFORMATION FbModeInfo;
+    PXTBL_FRAMEBUFFER_PROTOCOL FrameBufProtocol;
     PKERNEL_INITIALIZATION_BLOCK LoaderBlock;
-    EFI_PHYSICAL_ADDRESS Address;
+    EFI_HANDLE ProtocolHandle;
     EFI_STATUS Status;
-    UINT BlockPages;
+    ULONG_PTR FbSize;
-    UINT ParametersSize;
+
+    EFI_GUID FrameBufGuid = XT_FRAMEBUFFER_PROTOCOL_GUID;
+
+    /* Initialize Framebuffer information */
+    FbPhysicalAddress = 0;
+    FbSize = 0;
+    FbVirtualAddress = NULLPTR;
+    FbPages = 0;
 
     /* Calculate size of parameters */
     ParametersSize = (XtLdrProtocol->WideString.Length(Parameters->Parameters, 0) + 1) * sizeof(WCHAR);
 
     /* Calculate number of pages needed for initialization block */
     BlockPages = EFI_SIZE_TO_PAGES(sizeof(KERNEL_INITIALIZATION_BLOCK) + ParametersSize);
+    ResourcesPages = EFI_SIZE_TO_PAGES(sizeof(SYSTEM_RESOURCE_ACPI) + sizeof(SYSTEM_RESOURCE_FRAMEBUFFER));
 
-    /* Allocate memory for kernel initialization block */
+    /* Query Framebuffer size for allocation */
-    Status = XtLdrProtocol->Memory.AllocatePages(AllocateAnyPages, BlockPages, &Address);
+    if(XtLdrProtocol->Protocol.Open(&ProtocolHandle, (PVOID*)&FrameBufProtocol, &FrameBufGuid) == STATUS_EFI_SUCCESS)
+    {
+        /* Get FrameBuffer information */
+        FrameBufProtocol->GetDisplayInformation(&FbPhysicalAddress, &FbSize, &FbModeInfo);
+        XtLdrProtocol->Protocol.Close(&ProtocolHandle, &FrameBufGuid);
+    }
+    FbPages = EFI_SIZE_TO_PAGES(FbSize);
+
+    /* Calculate number of pages needed for memory descriptor list */
+    DescriptorPages = EFI_SIZE_TO_PAGES(PageMap->MapSize * sizeof(LOADER_MEMORY_DESCRIPTOR));
+
+    /* Allocate memory for the kernel initialization block and boot parameters */
+    Status = XtLdrProtocol->Memory.AllocatePages(AllocateAnyPages, BlockPages, &PhysicalBlock);
     if(Status != STATUS_EFI_SUCCESS)
     {
-        /* Memory allocation failure */
+        /* Memory allocation failure, return status code */
         return Status;
     }
 
-    /* Initialize and zero-fill kernel initialization block */
+    /* Allocate memory for the system resources data structures */
-    LoaderBlock = (PKERNEL_INITIALIZATION_BLOCK)(UINT_PTR)Address;
+    Status = XtLdrProtocol->Memory.AllocatePages(AllocateAnyPages, ResourcesPages, &PhysicalResources);
-    XtLdrProtocol->Memory.ZeroMemory(LoaderBlock, sizeof(KERNEL_INITIALIZATION_BLOCK) + ParametersSize);
+    if(Status != STATUS_EFI_SUCCESS)
+    {
+        /* Memory allocation failure, return status code */
+        return Status;
+    }
+
+    /* Allocate memory for the memory descriptor list */
+    Status = XtLdrProtocol->Memory.AllocatePages(AllocateAnyPages, DescriptorPages, &PhysicalDescriptor);
+    if(Status != STATUS_EFI_SUCCESS)
+    {
+        /* Memory allocation failure, return status code */
+        return Status;
+    }
+
+    /* Map the Kernel Initialization Block into virtual memory and advance the virtual address pointer */
+    VirtualBlock = *VirtualAddress;
+    XtLdrProtocol->Memory.MapVirtualMemory(PageMap, (ULONGLONG)VirtualBlock, PhysicalBlock, BlockPages, LoaderSystemBlock);
+    *VirtualAddress = (PUINT8)*VirtualAddress + (BlockPages * EFI_PAGE_SIZE);
+
+    /* Map the system resources physical memory into virtual address space and update the allocation pointer */
+    VirtualResources = *VirtualAddress;
+    XtLdrProtocol->Memory.MapVirtualMemory(PageMap, (ULONGLONG)VirtualResources, PhysicalResources, ResourcesPages, LoaderFirmwarePermanent);
+    *VirtualAddress = (PUINT8)*VirtualAddress + (ResourcesPages * EFI_PAGE_SIZE);
+
+    /* Check if a framebuffer was detected and requires memory mapping */
+    if(FbPages > 0)
+    {
+        /* Map the framebuffer physical memory range into virtual address space */
+        FbVirtualAddress = *VirtualAddress;
+        XtLdrProtocol->Memory.MapVirtualMemory(PageMap, (ULONGLONG)FbVirtualAddress, FbPhysicalAddress, FbPages, LoaderFirmwarePermanent);
+        *VirtualAddress = (PUINT8)*VirtualAddress + (FbPages * EFI_PAGE_SIZE);
+    }
+
+    /* Map the allocated physical memory for memory descriptors into the virtual address space */
+    VirtualDescriptor = *VirtualAddress;
+    XtLdrProtocol->Memory.MapVirtualMemory(PageMap, (ULONGLONG)VirtualDescriptor, PhysicalDescriptor, DescriptorPages, LoaderMemoryData);
+    *VirtualAddress = (PUINT8)*VirtualAddress + (DescriptorPages * EFI_PAGE_SIZE);
 
     /* Set basic loader block properties */
+    XtLdrProtocol->Memory.ZeroMemory((PVOID)PhysicalBlock, sizeof(KERNEL_INITIALIZATION_BLOCK) + ParametersSize);
+    LoaderBlock = (PKERNEL_INITIALIZATION_BLOCK)PhysicalBlock;
     LoaderBlock->BlockSize = sizeof(KERNEL_INITIALIZATION_BLOCK);
     LoaderBlock->BlockVersion = INITIALIZATION_BLOCK_VERSION;
     LoaderBlock->ProtocolVersion = BOOT_PROTOCOL_VERSION;
@@ -467,24 +476,30 @@ Xtos::InitializeLoaderBlock(IN PXTBL_PAGE_MAPPING PageMap,
     LoaderBlock->FirmwareInformation.EfiFirmware.EfiRuntimeServices = NULLPTR;
 
     /* Copy parameters to kernel initialization block */
-    LoaderBlock->KernelParameters = (PWCHAR)((UINT_PTR)*VirtualAddress + sizeof(KERNEL_INITIALIZATION_BLOCK));
+    LoaderBlock->KernelParameters = (PWCHAR)((UINT_PTR)VirtualBlock + sizeof(KERNEL_INITIALIZATION_BLOCK));
     XtLdrProtocol->Memory.CopyMemory((PVOID)((UINT_PTR)LoaderBlock + sizeof(KERNEL_INITIALIZATION_BLOCK)),
-                  Parameters->Parameters,
+                                     Parameters->Parameters, ParametersSize);
-                  ParametersSize);
 
-    /* Map kernel initialization block */
+    /* Commit mappings */
-    XtLdrProtocol->Memory.MapVirtualMemory(PageMap, (ULONGLONG)*VirtualAddress, (ULONGLONG)LoaderBlock,
+    XtLdrProtocol->Memory.CommitPageMap(PageMap);
-                                           BlockPages, LoaderSystemBlock);
-
-    /* Calculate next valid virtual address */
-    *VirtualAddress = (PUINT8)*VirtualAddress + (BlockPages * EFI_PAGE_SIZE);
 
+    /* Initialize system resources list */
     XtLdrProtocol->LinkedList.InitializeHead(&LoaderBlock->SystemResourcesListHead);
-    GetSystemResourcesList(PageMap, VirtualAddress, &LoaderBlock->SystemResourcesListHead);
+    Status = GetSystemResourcesList(PageMap, PhysicalResources, VirtualResources, FbVirtualAddress, &LoaderBlock->SystemResourcesListHead);
+    if(Status != STATUS_EFI_SUCCESS)
+    {
+        /* Failed to initialize system resources list, return status code */
+        return Status;
+    }
 
     /* Initialize memory descriptor list */
     XtLdrProtocol->LinkedList.InitializeHead(&LoaderBlock->MemoryDescriptorListHead);
-    GetMemoryDescriptorList(PageMap, VirtualAddress, &LoaderBlock->MemoryDescriptorListHead);
+    Status = GetMemoryDescriptorList(PageMap, PhysicalDescriptor, VirtualDescriptor, &LoaderBlock->MemoryDescriptorListHead);
+    if(Status != STATUS_EFI_SUCCESS)
+    {
+        /* Failed to initialize memory descriptor list, return status code */
+        return Status;
+    }
 
     /* Set boot image size */
     LoaderBlock->BootImageSize = (PFN_NUMBER)(((ULONGLONG)*VirtualAddress - KSEG0_BASE) / EFI_PAGE_SIZE);
@@ -702,6 +717,14 @@ Xtos::RunBootSequence(IN PEFI_FILE_HANDLE BootDir,
         return Status;
     }
 
+    /* Build page map */
+    Status = BuildPageMap(&PageMap);
+    if(Status != STATUS_EFI_SUCCESS)
+    {
+        XtLdrProtocol->Debug.Print(L"Failed to build page map (Status code: %zX)\n", Status);
+        return Status;
+    }
+
     /* Store virtual address of kernel initialization block for future kernel call */
     KernelParameters = (PKERNEL_INITIALIZATION_BLOCK)VirtualAddress;
 

boot/xtldr/protocol.cc

@@ -1054,6 +1054,7 @@ Protocol::InstallXtLoaderProtocol()
     LoaderProtocol.Memory.AllocatePages = Memory::AllocatePages;
     LoaderProtocol.Memory.AllocatePool = Memory::AllocatePool;
     LoaderProtocol.Memory.BuildPageMap = Memory::BuildPageMap;
+    LoaderProtocol.Memory.CommitPageMap = Memory::CommitPageMap;
     LoaderProtocol.Memory.CompareMemory = RTL::Memory::CompareMemory;
     LoaderProtocol.Memory.CopyMemory = RTL::Memory::CopyMemory;
     LoaderProtocol.Memory.FreePages = Memory::FreePages;

sdk/xtdk/bltypes.h

@@ -51,6 +51,7 @@ typedef EFI_STATUS (XTCDECL *PBL_BOOTMENU_INITIALIZE_OS_LIST)(IN ULONG MaxNameLe
 typedef BOOLEAN (XTCDECL *PBL_BOOTUTILS_GET_BOOLEAN_PARAMETER)(IN PCWSTR Parameters, IN PCWSTR Needle);
 typedef VOID (XTAPI *PBL_BOOTUTILS_GET_TRAMPOLINE_INFORMATION)(IN TRAMPOLINE_TYPE TrampolineType, OUT PVOID *TrampolineCode, OUT PULONG_PTR TrampolineSize);
 typedef EFI_STATUS (XTCDECL *PBL_BUILD_PAGE_MAP)(IN PXTBL_PAGE_MAPPING PageMap, IN ULONG_PTR SelfMapAddress);
+typedef EFI_STATUS (XTCDECL *PBL_COMMIT_PAGE_MAP)(IN PXTBL_PAGE_MAPPING PageMap);
 typedef EFI_STATUS (XTCDECL *PBL_CLOSE_VOLUME)(IN PEFI_HANDLE VolumeHandle);
 typedef VOID (XTCDECL *PBL_CLEAR_CONSOLE_LINE)(IN ULONGLONG LineNo);
 typedef BOOLEAN (XTCDECL *PBL_CPU_CPUID)(IN OUT PCPUID_REGISTERS Registers);
@@ -449,6 +450,7 @@ typedef struct _XTBL_LOADER_PROTOCOL
         PBL_ALLOCATE_PAGES AllocatePages;
         PBL_ALLOCATE_POOL AllocatePool;
         PBL_BUILD_PAGE_MAP BuildPageMap;
+        PBL_COMMIT_PAGE_MAP CommitPageMap;
         PBL_COMPARE_MEMORY CompareMemory;
         PBL_COPY_MEMORY CopyMemory;
         PBL_FREE_PAGES FreePages;