From mboxrd@z Thu Jan  1 00:00:00 1970
From: Matt Fleming <matt-mF/unelCI9GS6iBeEJttW/XRex20P6io@public.gmane.org>
Subject: Re: [PATCH v2 4/5] efi: implement generic support for the Memory
 Attributes table
Date: Tue, 12 Apr 2016 20:57:27 +0100
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To: Ard Biesheuvel <ard.biesheuvel-QSEj5FYQhm4dnm+yROfE0A@public.gmane.org>
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List-Id: linux-efi@vger.kernel.org

On Mon, 11 Apr, at 04:09:11PM, Ard Biesheuvel wrote:
> 
> The spec does not actually mandate that, and I do know that the
> Tianocore code deliberately uses a larger value for desc_size in
> GetMemoryMap() to catch inadvertent uses of sizeof(). I am not sure if
> the memory attribute table code does the same, and it seems dangerous
> to assume that to be the case in general.
 
The spec may not mandate that, but this code will explode horribly if
efi_memory_desc_t does not accurately describe the entries in either
the EFI Memory Attributes table or the EFI memory map.

How do we ensure that doing,

static bool entry_is_valid(...)
{
	*out = *in;
	...

keeps working? Are we using the table version to guarantee that?