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Date:   Tue, 28 Jun 2022 01:38:08 +0300
From:   "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>
To:     Ard Biesheuvel <ardb@kernel.org>
Cc:     Peter Gonda <pgonda@google.com>, Borislav Petkov <bp@alien8.de>,
        Andy Lutomirski <luto@kernel.org>,
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        <sathyanarayanan.kuppuswamy@linux.intel.com>,
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Subject: Re: [PATCHv7 00/14] mm, x86/cc: Implement support for unaccepted
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On Mon, Jun 27, 2022 at 06:33:51PM +0200, Ard Biesheuvel wrote:
> > > > >
> > > > > Just as an idea, we can put info into UTS_VERSION which can be read from
> > > > > the built bzImage. We have info on SMP and preeption there already.
> > > > >
> > > >
> > > > Instead of hacking this into the binary, couldn't we define a protocol
> > > > that the kernel will call from the EFI stub (before EBS()) to identify
> > > > itself as an image that understands unaccepted memory, and knows how
> > > > to deal with it?
> > > >
> > > > That way, the firmware can accept all the memory on behalf of the OS
> > > > at ExitBootServices() time, unless the OS has indicated there is no
> > > > need to do so.
> > >
> > > I agree it would be better. But I think it would require change to EFI
> > > spec, no?
> >
> > Could this somehow be amended on to the UEFI Specification version 2.9
> > change which added all of the unaccepted memory features?
> >
> 
> Why would this need a change in the EFI spec? Not every EFI protocol
> needs to be in the spec.

My EFI knowledge is shallow. Do we do this in other cases?

-- 
 Kirill A. Shutemov