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Subject: Re: [PATCH] x86/acpi: check rsdp address received via bootparams to
 be valid
To: Ingo Molnar <mingo@kernel.org>, "H. Peter Anvin" <hpa@zytor.com>
Cc: linux-kernel@vger.kernel.org, linux-acpi@vger.kernel.org,
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From: Juergen Gross <jgross@suse.com>
Message-ID: <1d6083f2-0a3e-2f3a-7089-426f81e8af93@suse.com>
Date: Tue, 13 Feb 2018 17:48:43 +0100
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On 13/02/18 17:32, Ingo Molnar wrote:
> 
> * 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.

Okay, thanks for the feedback.

I'll go that route.

> I've removed the patches for the time being.

Seems a sensible thing to do.


Juergen