RE: [PATCH v2 1/2] x86/mce/AMD: Redo use of SMCA MCA_DE{STAT,ADDR} registers

From	"Ghannam, Yazen" <Yazen.Ghannam@amd.com>
Newsgroups	linux.kernel
Subject	RE: [PATCH v2 1/2] x86/mce/AMD: Redo use of SMCA MCA_DE{STAT,ADDR} registers
Date	2017-04-11 15:40 +0200
Message-ID	<tv4bw-7C6-21@gated-at.bofh.it> (permalink)
References	(6 earlier) <ttJLQ-4Kd-5@gated-at.bofh.it> <tv3yO-77s-15@gated-at.bofh.it> <tv3Sa-7tH-15@gated-at.bofh.it> <tv3Sa-7tH-17@gated-at.bofh.it> <tv41Q-7yR-7@gated-at.bofh.it>
Organization	linux.* mail to news gateway

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> -----Original Message-----
> From: Borislav Petkov [mailto:bp@alien8.de]
> Sent: Tuesday, April 11, 2017 9:25 AM
> To: Ghannam, Yazen <Yazen.Ghannam@amd.com>
> Cc: linux-edac@vger.kernel.org; Tony Luck <tony.luck@intel.com>;
> x86@kernel.org; linux-kernel@vger.kernel.org
> Subject: Re: [PATCH v2 1/2] x86/mce/AMD: Redo use of SMCA
> MCA_DE{STAT,ADDR} registers
> 
> On Tue, Apr 11, 2017 at 01:18:50PM +0000, Ghannam, Yazen wrote:
> > So log_error() reads/clears MCA_STATUS, right? This won't affect
> > MCA_DESTAT on SMCA systems. So if we call log_error_smca() and
> > unconditionally read MCA_DESTAT, we will find the same deferred error
> that we logged in log_error().
> 
> I'm reading this as, "we log the same deferred error in *both* the original
> MCA MSRs and in the new DE* ones". Correct?
> 

Yes, exactly. Deferred errors are *always* logged in the DE* registers and
they are logged in the original MSRs based on the MCA_CONFIG bit.

The idea here is that if a deferred error is overwritten in MCA_STATUS we
will still have a copy logged in MCA_DESTAT.

Thanks,
Yazen

Thread

RE: [PATCH v2 1/2] x86/mce/AMD: Redo use of SMCA MCA_DE{STAT,ADDR}  registers "Ghannam, Yazen" <Yazen.Ghannam@amd.com> - 2017-04-11 15:00 +0200
  Re: [PATCH v2 1/2] x86/mce/AMD: Redo use of SMCA MCA_DE{STAT,ADDR}  registers Borislav Petkov <bp@alien8.de> - 2017-04-11 15:20 +0200
    RE: [PATCH v2 1/2] x86/mce/AMD: Redo use of SMCA MCA_DE{STAT,ADDR}  registers "Ghannam, Yazen" <Yazen.Ghannam@amd.com> - 2017-04-11 15:20 +0200
      Re: [PATCH v2 1/2] x86/mce/AMD: Redo use of SMCA MCA_DE{STAT,ADDR}  registers Borislav Petkov <bp@alien8.de> - 2017-04-11 15:30 +0200
        RE: [PATCH v2 1/2] x86/mce/AMD: Redo use of SMCA MCA_DE{STAT,ADDR}  registers "Ghannam, Yazen" <Yazen.Ghannam@amd.com> - 2017-04-11 15:40 +0200
          Re: [PATCH v2 1/2] x86/mce/AMD: Redo use of SMCA MCA_DE{STAT,ADDR}  registers Borislav Petkov <bp@alien8.de> - 2017-04-11 15:40 +0200
            Re: [PATCH v2 1/2] x86/mce/AMD: Redo use of SMCA MCA_DE{STAT,ADDR}  registers Borislav Petkov <bp@alien8.de> - 2017-04-11 16:00 +0200
            RE: [PATCH v2 1/2] x86/mce/AMD: Redo use of SMCA MCA_DE{STAT,ADDR}  registers "Ghannam, Yazen" <Yazen.Ghannam@amd.com> - 2017-04-11 16:00 +0200

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