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Subject: Re: [RFC Part1 PATCH v3 02/17] x86/CPU/AMD: Add the Secure Encrypted
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To: Borislav Petkov <bp@suse.de>
Cc: Brijesh Singh <brijesh.singh@amd.com>, linux-kernel@vger.kernel.org,
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From: Tom Lendacky <thomas.lendacky@amd.com>
Message-ID: <b2aedd44-ebbc-b196-31d0-0b423f4fa632@amd.com>
Date: Wed, 9 Aug 2017 13:17:54 -0500
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On 7/25/2017 10:33 AM, Borislav Petkov wrote:
> On Tue, Jul 25, 2017 at 10:29:40AM -0500, Tom Lendacky wrote:
>> But early_identify_cpu() calls get_cpu_cap() which will check for cpuid
>> leaf 0x80000008 support and set x86_phys_bits.
> 
> Right, but it can't be less than 32, can it? And if it is more than 32
> bits, then it probably doesn't really matter on 32-bit. Unless it is
> less than 36 bits and you do PAE...
> 
>> I'll try to build and run a 32-bit kernel and see how this all flows.
> 
> Yeah, that would be good.

Ok, finally got around to running a 32-bit kernel and it reports
x86_phys_bits as 48.

Thanks,
Tom

> 
> Thanks.
>