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Date: Tue, 13 Feb 2018 17:32:44 +0100
From: Ingo Molnar <mingo@kernel.org>
To: Juergen Gross <jgross@suse.com>, "H. Peter Anvin" <hpa@zytor.com>
Cc: linux-kernel@vger.kernel.org, linux-acpi@vger.kernel.org,
        x86@kernel.org, lenb@kernel.org, rafael.j.wysocki@intel.com,
        hpa@zytor.com, tglx@linutronix.de, mingo@redhat.com
Subject: Re: [PATCH] x86/acpi: check rsdp address received via bootparams to
 be valid
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* Juergen Gross <jgross@suse.com> wrote:

> So what about the following:
> 
> From version 0x020e on (current version without my patches is 0x020d)
> the boot loader will write its supported version or'ed with 0x8000 into
> the same version field. So we can be sure any added fields are filled
> with real data or the information has been evaluated by the boot loader,
> if the returned version included that field. If the boot loader finds
> the kernel supports a version < 0x020e it won't return its supported
> version.

This seems like a usable workaround to me, as long as everyone involved
agrees with it.

I've removed the patches for the time being.

Thanks,

	Ingo