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Date:   Thu, 5 Sep 2019 13:20:19 -0700
From:   "Raj, Ashok" <ashok.raj@intel.com>
To:     Borislav Petkov <bp@alien8.de>
Cc:     Boris Ostrovsky <boris.ostrovsky@oracle.com>,
        Mihai Carabas <mihai.carabas@oracle.com>,
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        Ashok Raj <ashok.raj@intel.com>
Subject: Re: [PATCH] x86/microcode: Add an option to reload microcode even if
 revision is unchanged
Message-ID: <20190905202019.GA3649@otc-nc-03>
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On Thu, Sep 05, 2019 at 09:49:50PM +0200, Borislav Petkov wrote:
> On Thu, Sep 05, 2019 at 12:40:44PM -0700, Raj, Ashok wrote:
> > The original description said to load a new microcode file, the content
> > could have changed, but revision in the header hasn't increased.
> 
> How does the hardware even accept a revision which is the same as the
> one already loaded?

Hardware will allow a reload as long as the loaded ucode svn <= the version being updated.