Re: [PATCH 3/4] EFI: Add support for variables longer than 1024 bytes

From: H. Peter Anvin
Date: Wed Dec 14 2011 - 17:58:29 EST


On 12/14/2011 02:57 PM, Matthew Garrett wrote:
> On Wed, Dec 14, 2011 at 02:44:34PM -0800, H. Peter Anvin wrote:
>> On 12/14/2011 02:39 PM, Matthew Garrett wrote:
>>>> What are your thoughts on _not_ wrapping efi_variable with
>>>> extended_efi_variable, and instead just using a
>>>> "internal_efi_variable" structure that we copy stuff into/outof. I
>>>> think that would make the memory management for dealing with the
>>>> different sizes a lot easier to follow.
>>>
>>> Hm. I think that'd only work if we expose a new interface. Writes would
>>> be easy enough to handle, but reads still need to work for old apps.
>>>
>>
>> Would making the old ABI readonly and add a new write interface resolve
>> the problem with compat mode?
>
> Yes, but we'd break existing userspace.
>

Obviously. However, you indicated above that that might be acceptable
-- how many things use this ABI to set variables?

-hpa

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