Re: [edk2-devel] [RFC PATCH 1/3] MdePkg: Update MemoryAttributesTable to v2.10

["Michael Kubacki" <mikuback@linux.microsoft.com>]

Acked-by: Michael Kubacki <michael.kubacki@microsoft.com>

Might be convenient to have a link in the commit message to the 
definition in the 2.10 spec:

https://uefi.org/specs/UEFI/2.10/04_EFI_System_Table.html?highlight=memory_attribute#efi-memory-attributes-table

On 2/2/2023 1:03 PM, Ard Biesheuvel wrote:
> UEFI v2.10 introduces a new flag to the memory attributes table to
> inform the OS whether or not runtime services code regions were emitted
> by the compiler with guard instructions for forward edge control flow
> integrity enforcement.
> 
> So update our definition accordingly.
> 
> Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
> ---
>   MdePkg/Include/Guid/MemoryAttributesTable.h | 8 ++++++--
>   1 file changed, 6 insertions(+), 2 deletions(-)
> 
> diff --git a/MdePkg/Include/Guid/MemoryAttributesTable.h b/MdePkg/Include/Guid/MemoryAttributesTable.h
> index 82f83a67b96d..238c14ff92df 100644
> --- a/MdePkg/Include/Guid/MemoryAttributesTable.h
> +++ b/MdePkg/Include/Guid/MemoryAttributesTable.h
> @@ -17,11 +17,15 @@ typedef struct {
>     UINT32    Version;
> 
>     UINT32    NumberOfEntries;
> 
>     UINT32    DescriptorSize;
> 
> -  UINT32    Reserved;
> 
> +  UINT32    Flags;
> 
>     // EFI_MEMORY_DESCRIPTOR Entry[1];
> 
>   } EFI_MEMORY_ATTRIBUTES_TABLE;
> 
>   
> 
> -#define EFI_MEMORY_ATTRIBUTES_TABLE_VERSION  0x00000001
> 
> +#define EFI_MEMORY_ATTRIBUTES_TABLE_VERSION  0x00000002
> 
> +
> 
> +#define EFI_MEMORY_ATTRIBUTES_FLAGS_RT_FORWARD_CONTROL_FLOW_GUARD  0x1
> 
> +// BIT0 implies that Runtime code includes the forward control flow guard
> 
> +// instruction, such as X86 CET-IBT or ARM BTI.
> 
>   
> 
>   extern EFI_GUID  gEfiMemoryAttributesTableGuid;
> 
>   
>