Date:   Fri, 12 Nov 2021 07:52:13 +0100
From:   Greg KH <gregkh@linuxfoundation.org>
To:     Richard Hughes <hughsient@gmail.com>
Cc:     Andy Shevchenko <andy.shevchenko@gmail.com>,
        Ard Biesheuvel <ardb@kernel.org>,
        Hans-Gert Dahmen <hans-gert.dahmen@immu.ne>,
        Mika Westerberg <mika.westerberg@linux.intel.com>,
        Mauro Lima <mauro.lima@eclypsium.com>,
        "akpm@linux-foundation.org" <akpm@linux-foundation.org>,
        "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
        Philipp Deppenwiese <philipp.deppenwiese@immu.ne>,
        "platform-driver-x86@vger.kernel.org" 
        <platform-driver-x86@vger.kernel.org>
Subject: Re: [PATCH] firmware: export x86_64 platform flash bios region via
 sysfs
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On Thu, Nov 11, 2021 at 09:07:42PM +0000, Richard Hughes wrote:
> On Thu, 11 Nov 2021 at 15:50, Andy Shevchenko <andy.shevchenko@gmail.com> wrote:
> > I was thinking about SHA256 hashes or so (as they tell about
> > binaries). In any case the interface for this seems to be in the
> > kernel.
> 
> I'm quite sure you don't want to put those EFI format decoders in the
> kernel; there is all kinds of weird compression schemes, volumes are
> recursive, and vendors like to hide weird things in the undocumented
> (or reserved) areas.

Why don't we just export these areas to userspace and let the decoding
of them happen there?  That's a real "thing" that the kernel can easily
detect is present and know to export properly as they are defined by the
UEFI specification, right?

Yes, that will not help for the non-UEFI x86 systems, but it's a
start...

thanks,

greg k-h