linux-kernel - Re: [PATCH v2] x86/mce: add support SRAO reported via CMC check

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Message-ID: <20171127101926.7u5h5g6mfotwpfca@pd.tnic>
Date:   Mon, 27 Nov 2017 11:19:26 +0100
From:   Borislav Petkov <bp@...en8.de>
To:     Xie XiuQi <xiexiuqi@...wei.com>
Cc:     tony.luck@...el.com, tglx@...utronix.de, mingo@...hat.com,
        hpa@...or.com, x86@...nel.org, linux-edac@...r.kernel.org,
        linux-kernel@...r.kernel.org, chenwei68@...wei.com
Subject: Re: [PATCH v2] x86/mce: add support SRAO reported via CMC check

On Sat, Nov 25, 2017 at 10:05:48AM +0800, Xie XiuQi wrote:
> In Intel SDM Volume 3B (253669-063US, July 2017), SRAO could be
> reported either via MCE or CMC:
> 
>   In cases when SRAO is signaled via CMCI the error signature is
>   indicated via UC=1, PCC=0, S=0.
> 
>   Type(*1)	UC	EN	PCC	S	AR	Signaling
>   ---------------------------------------------------------------
>   UC		1	1	1	x	x	MCE
>   SRAR		1	1	0	1	1	MCE
>   SRAO		1	x(*2)	0	x(*2)	0	MCE/CMC
>   UCNA		1	x	0	0	0	CMC
>   CE		0	x	x	x	x	CMC
> 
>   NOTES:
>   1. SRAR, SRAO and UCNA errors are supported by the processor only
>      when IA32_MCG_CAP[24] (MCG_SER_P) is set.
>   2. EN=1, S=1 when signaled via MCE. EN=x, S=0 when signaled via CMC.
> 
> And there is a description in 15.6.2 UCR Error Reporting and Logging, for bit S:
> 
>   S (Signaling) flag, bit 56 - Indicates (when set) that a machine check
>   exception was generated for the UCR error reported in this MC bank...
>   When the S flag in the IA32_MCi_STATUS register is clear, this UCR error
>   was not signaled via a machine check exception and instead was reported
>   as a corrected machine check (CMC).
> 
> So we could merge this two case, and just remove the S=0 check for SRAO
> in mce_severity().
> 
> ---
> v2: add OVER=0 check and merge MCE and CMC case.
> 
> Signed-off-by: Xie XiuQi <xiexiuqi@...wei.com>
> Tested-by: Chen Wei <chenwei68@...wei.com>
> Reviewed-by: Tony Luck <tony.luck@...el.com>
> ---
>  arch/x86/kernel/cpu/mcheck/mce-severity.c | 26 +++++++++++++++++---------
>  1 file changed, 17 insertions(+), 9 deletions(-)

Applied, thanks.

-- 
Regards/Gruss,
    Boris.

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