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Date:   Tue, 16 Aug 2022 14:41:39 +0200
From:   Borislav Petkov <bp@alien8.de>
To:     Ashok Raj <ashok_raj@linux.intel.com>
Cc:     X86 ML <x86@kernel.org>, Andrew Cooper <amc96@srcf.net>,
        LKML <linux-kernel@vger.kernel.org>,
        =?utf-8?Q?=C8=98tefan?= Talpalaru <stefantalpalaru@yahoo.com>,
        Ashok Raj <ashok.raj@intel.com>
Subject: Re: [PATCH] x86/microcode/AMD: Attempt applying on every logical
 thread
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References: <20220814120026.16118-1-bp@alien8.de>
 <YvtcGEHX8eSFpALX@araj-dh-work>
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On Tue, Aug 16, 2022 at 09:00:14AM +0000, Ashok Raj wrote:
> A re-application means, you want to apply even if the cpu_rev <= patch.rev

Yes.

> if cpu_rev is > patch_rev, clearly its ahead?. say BIOS has a newer
> version than in the initrd image, do we want to replace the BIOS
> version since we do no revid checks here.

Can you even downgrade the microcode through the MSR?

-- 
Regards/Gruss,
    Boris.

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