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 X-Spam-Level: X-Spam-Status: No, score=-0.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 2070FC31E4A for ; Thu, 13 Jun 2019 17:00:58 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id EAF7320665 for ; Thu, 13 Jun 2019 17:00:57 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2393153AbfFMRAt (ORCPT ); Thu, 13 Jun 2019 13:00:49 -0400 Received: from gate.crashing.org ([63.228.1.57]:49136 "EHLO gate.crashing.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729758AbfFLX4n (ORCPT ); Wed, 12 Jun 2019 19:56:43 -0400 Received: from localhost (localhost.localdomain [127.0.0.1]) by gate.crashing.org (8.14.1/8.14.1) with ESMTP id x5CNuKVE016725; Wed, 12 Jun 2019 18:56:21 -0500 Message-ID: <78de2a9768cfd7d871d3b61f64ce18aefc8c3293.camel@kernel.crashing.org> Subject: Re: [PATCH 2/2] edac: add support for Amazon's Annapurna Labs EDAC From: Benjamin Herrenschmidt To: Borislav Petkov , Mauro Carvalho Chehab Cc: James Morse , "Hawa, Hanna" , "robh+dt@kernel.org" , "Woodhouse, David" , "paulmck@linux.ibm.com" , "mark.rutland@arm.com" , "gregkh@linuxfoundation.org" , "davem@davemloft.net" , "nicolas.ferre@microchip.com" , "devicetree@vger.kernel.org" , "Shenhar, Talel" , "linux-kernel@vger.kernel.org" , "Chocron, Jonathan" , "Krupnik, Ronen" , "linux-edac@vger.kernel.org" , "Hanoch, Uri" Date: Thu, 13 Jun 2019 09:56:20 +1000 In-Reply-To: <20190612110039.GH32652@zn.tnic> References: <32431fa2-2285-6c41-ce32-09630205bb54@arm.com> <9a2aaf4a9545ed30568a0613e64bc3f57f047799.camel@kernel.crashing.org> <20190608090556.GA32464@zn.tnic> <1ae5e7a3464f9d8e16b112cd371957ea20472864.camel@kernel.crashing.org> <68446361fd1e742b284555b96b638fe6b5218b8b.camel@kernel.crashing.org> <20190611115651.GD31772@zn.tnic> <6df5a17bb1c900dc69b991171e55632f40d9426f.camel@kernel.crashing.org> <20190612034813.GA32652@zn.tnic> <08bd58dc0045670223f8d3bbc8be774505bd3ddf.camel@kernel.crashing.org> <20190612074242.53a4cf56@coco.lan> <20190612110039.GH32652@zn.tnic> Content-Type: text/plain; charset="UTF-8" X-Mailer: Evolution 3.28.5-0ubuntu0.18.04.1 Mime-Version: 1.0 Content-Transfer-Encoding: 7bit Sender: linux-edac-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-edac@vger.kernel.org On Wed, 2019-06-12 at 13:00 +0200, Borislav Petkov wrote: > On Wed, Jun 12, 2019 at 07:42:42AM -0300, Mauro Carvalho Chehab wrote: > > That's said, from the admin PoV, it makes sense to have a single > > daemon that collect errors from all error sources and take the > > needed actions. > > Doing recovery actions in userspace is too flaky. Daemon can get killed > at any point in time So what ? If root kills your RAS daemon, then so be it. That has never been a problem on POWER8/POWER9 server platforms and those have some of the nastiest RAS in town. You can kill PID 1 too you know ... > and there are error types where you want to do recovery *before* you return to userspace. Very few (precise examples please) and I yet have to see why those need some kind of magic coordinator. > Yes, we do have different error reporting facilities but I still think > that concentrating all the error information needed in order to do > proper recovery action is the better approach here. And make that part > of the kernel so that it is robust. Userspace can still configure it and > so on. Ben.