From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 1EC16C00140 for ; Mon, 8 Aug 2022 17:25:00 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S236872AbiHHRY6 (ORCPT ); Mon, 8 Aug 2022 13:24:58 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:33856 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S243226AbiHHRY4 (ORCPT ); Mon, 8 Aug 2022 13:24:56 -0400 Received: from shelob.surriel.com (shelob.surriel.com [96.67.55.147]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id AE020167EB for ; Mon, 8 Aug 2022 10:24:55 -0700 (PDT) Received: from imladris.surriel.com ([96.67.55.152]) by shelob.surriel.com with esmtpsa (TLS1.2) tls TLS_ECDHE_ECDSA_WITH_AES_256_GCM_SHA384 (Exim 4.95) (envelope-from ) id 1oL6Ue-0008EX-LY; Mon, 08 Aug 2022 13:24:44 -0400 Message-ID: <06dc568d91979a3816af602a00884560cb5ec026.camel@surriel.com> Subject: Re: [RFC PATCH 5/5] x86/entry: Store CPU info on exception entry From: Rik van Riel To: Dave Hansen , Ingo Molnar , Ira Weiny , Andy Lutomirski Cc: Borislav Petkov , x86@kernel.org, linux-kernel@vger.kernel.org, kernel-team@fb.com Date: Mon, 08 Aug 2022 13:24:43 -0400 In-Reply-To: <01768c70-a012-0d08-cfa5-a7a87ff0a19c@intel.com> References: <20220805173009.3128098-1-ira.weiny@intel.com> <20220805173009.3128098-6-ira.weiny@intel.com> <5d62c1d0-7425-d5bb-ecb5-1dc3b4d7d245@intel.com> <01768c70-a012-0d08-cfa5-a7a87ff0a19c@intel.com> Content-Type: multipart/signed; micalg="pgp-sha256"; protocol="application/pgp-signature"; boundary="=-zLfyIRf1FZ4PsR+JaPBx" User-Agent: Evolution 3.42.4 (3.42.4-1.fc35) MIME-Version: 1.0 Sender: riel@shelob.surriel.com Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org --=-zLfyIRf1FZ4PsR+JaPBx Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable 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. --=-zLfyIRf1FZ4PsR+JaPBx Content-Type: application/pgp-signature; name="signature.asc" Content-Description: This is a digitally signed message part Content-Transfer-Encoding: 7bit -----BEGIN PGP SIGNATURE----- iQEzBAABCAAdFiEEKR73pCCtJ5Xj3yADznnekoTE3oMFAmLxRtsACgkQznnekoTE 3oPpIQf+M/woay+5/L9lVOq1s9YMpVHckK1DzaJLC9heGr3jDjMXrt9zJYouu2M9 p46Sylwg7nU4zxMKPfV4NMIHd+kDYK73jmF41Ypnm5lbtk+Z6LA/qNElmTlWF3I2 xZA1jpA5KarA+l/9vSdQyfcIJIo8xKxYDV8MLPEoX0EBZh5JA25rUH6dxPn3Rtjd 0DR8namlwZpkkWiWOp3ZzaYFqh0azwQLnrB56hVjHU3ckKunY7nEmn70cWnV9+7d /RSpDNG5MBLs1SFWebF1oWzhbv4XqNMr4KpI6HDVTYw1PmX7uw/G1KzHE7H558Fk KAZc0I/0VuzunNoBWPSEgjfoUCURTw== =gGXL -----END PGP SIGNATURE----- --=-zLfyIRf1FZ4PsR+JaPBx--