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Date:   Fri, 11 Feb 2022 15:09:12 -0600
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Subject: Re: [PATCH 1/2] x86: Use CPUID 0x8000001f to confirm SME availability
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To:     "Limonciello, Mario" <mario.limonciello@amd.com>,
        Borislav Petkov <bp@alien8.de>,
        "maintainer:X86 ARCHITECTURE (32-BIT AND 64-BIT)" <x86@kernel.org>
Cc:     Kees Cook <keescook@chromium.org>, hughsient@gmail.com,
        Martin Fernandez <martin.fernandez@eclypsium.com>,
        linux-kernel@vger.kernel.org
References: <20220211053652.64655-1-mario.limonciello@amd.com>
 <568d9945-ed0c-90a7-d9cf-a5662f1dbce2@amd.com>
 <a52990c0-3e54-a5f2-22c2-3446e92f4294@amd.com>
From:   Tom Lendacky <thomas.lendacky@amd.com>
In-Reply-To: <a52990c0-3e54-a5f2-22c2-3446e92f4294@amd.com>
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On 2/11/22 13:51, Limonciello, Mario wrote:
> On 2/11/2022 08:55, Tom Lendacky wrote:
>> On 2/10/22 23:36, Mario Limonciello wrote:

>      1254:       f6 45 d8 01             testb  $0x1,-0x28(%rbp)
>      1258:       74 02                   je     125c <stop_this_cpu+0x8c>
>      125a:       0f 09                   wbinvd
>      125c:       eb 07                   jmp    1265 <stop_this_cpu+0x95>
>      125e:       0f 00 2d 00 00 00 00    verw   0x0(%rip)        # 1265 
> <stop_this_cpu+0x95>
>      1265:       f4                      hlt
>      1266:       eb f4                   jmp    125c <stop_this_cpu+0x8c>

That appears to be the same as today after the WBINVD is issued, so should 
be good.

Thanks,
Tom

>