linux-kernel - Re: [PATCH 2/5] x86/mce/inject: Set the valid bit in MCA

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Message-ID: <YU2LtYZzt2L9D2Ja@zn.tnic>
Date:   Fri, 24 Sep 2021 10:26:29 +0200
From:   Borislav Petkov <bp@...en8.de>
To:     Smita Koralahalli <Smita.KoralahalliChannabasappa@....com>
Cc:     x86@...nel.org, linux-edac@...r.kernel.org,
        linux-kernel@...r.kernel.org, Tony Luck <tony.luck@...el.com>,
        "H . Peter Anvin" <hpa@...or.com>, yazen.ghannam@....com
Subject: Re: [PATCH 2/5] x86/mce/inject: Set the valid bit in MCA_STATUS
 before error injection

On Wed, Sep 15, 2021 at 06:27:36PM -0500, Smita Koralahalli wrote:
> MCA handlers check the valid bit in each status register (MCA_STATUS[Val])
> and examine the remainder of the status register only if the valid bit is
> set.
> 
> Set the valid bit in the corresponding MCA_STATUS register if the user
> forgets to set it while doing error simulation.

Why, maybe the user wants to inject with Val not set. You could warn
here instead and state that handlers will likely ignore signatures with
Val=0.

-- 
Regards/Gruss,
    Boris.

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