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Message-ID: <06dc568d91979a3816af602a00884560cb5ec026.camel@surriel.com>
Subject: Re: [RFC PATCH 5/5] x86/entry: Store CPU info on exception entry
From:   Rik van Riel <riel@surriel.com>
To:     Dave Hansen <dave.hansen@intel.com>,
        Ingo Molnar <mingo@kernel.org>,
        Ira Weiny <ira.weiny@intel.com>,
        Andy Lutomirski <luto@kernel.org>
Cc:     Borislav Petkov <bp@alien8.de>, x86@kernel.org,
        linux-kernel@vger.kernel.org, kernel-team@fb.com
Date:   Mon, 08 Aug 2022 13:24:43 -0400
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On Mon, 2022-08-08 at 09:16 -0700, Dave Hansen wrote:
> On 8/8/22 04:03, Ingo Molnar wrote:
> > > Again, I don't believe this is too much overhead but I don't want
> > > people=20
> > > to say it was not discussed.
> > Is it necessary to do this, what are the alternatives, can this
> > overhead be=20
> > avoided?
>=20
> I'm thinking that the whole racy smp_processor_id() thing wasn't so
> bad
> in the first place.
>=20

FWIW, just grabbing the CPU number in show_signal_msg()
appears to be good enough for our use.=C2=A0

It will typically show >90% of the errors happening on the
CPU core that went bad, which is more than enough to diagnose=C2=A0
that a server has a hardware issue and should probably have
the CPU repaired.

--=20
All Rights Reversed.

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