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=-2.2 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_1 autolearn=no 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 38D2EC3A5A5 for ; Thu, 5 Sep 2019 10:51:44 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 0BC07206BB for ; Thu, 5 Sep 2019 10:51:44 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2387966AbfIEKvm (ORCPT ); Thu, 5 Sep 2019 06:51:42 -0400 Received: from Galois.linutronix.de ([193.142.43.55]:42419 "EHLO Galois.linutronix.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1731476AbfIEKvm (ORCPT ); Thu, 5 Sep 2019 06:51:42 -0400 Received: from p5de0b6c5.dip0.t-ipconnect.de ([93.224.182.197] helo=nanos) by Galois.linutronix.de with esmtpsa (TLS1.2:DHE_RSA_AES_256_CBC_SHA256:256) (Exim 4.80) (envelope-from ) id 1i5pMG-0005iC-Gn; Thu, 05 Sep 2019 12:51:20 +0200 Date: Thu, 5 Sep 2019 12:51:18 +0200 (CEST) From: Thomas Gleixner To: Borislav Petkov cc: "Raj, Ashok" , Boris Ostrovsky , Mihai Carabas , "H. Peter Anvin" , Ingo Molnar , Jon Grimm , kanth.ghatraju@oracle.com, konrad.wilk@oracle.com, patrick.colp@oracle.com, Tom Lendacky , x86-ml , linux-kernel@vger.kernel.org Subject: Re: [PATCH] x86/microcode: Add an option to reload microcode even if revision is unchanged In-Reply-To: <20190905072029.GB19246@zn.tnic> Message-ID: References: <1567056803-6640-1-git-send-email-ashok.raj@intel.com> <20190829060942.GA1312@zn.tnic> <20190829130213.GA23510@araj-mobl1.jf.intel.com> <20190903164630.GF11641@zn.tnic> <41cee473-321c-2758-032a-ccf0f01359dc@oracle.com> <20190905002132.GA26568@otc-nc-03> <20190905072029.GB19246@zn.tnic> User-Agent: Alpine 2.21 (DEB 202 2017-01-01) MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII X-Linutronix-Spam-Score: -1.0 X-Linutronix-Spam-Level: - X-Linutronix-Spam-Status: No , -1.0 points, 5.0 required, ALL_TRUSTED=-1,SHORTCIRCUIT=-0.0001 Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, 5 Sep 2019, Borislav Petkov wrote: > On Wed, Sep 04, 2019 at 05:21:32PM -0700, Raj, Ashok wrote: > > But echo 2 > reload would allow reading a microcode file from > > /lib/firmware/intel-ucode/ even if the revision hasn't changed right? > > > > #echo 1 > reload wouldn't load if the revision on disk is same as what's loaded, > > and we want to permit that with the echo 2 option. > > Then before we continue with this, please specify what the exact > requirements are. Talk to your microcoders or whoever is going to use > this and give the exact use cases which should be supported and describe > them in detail. Plus I have to ask whether this facility makes any sense outside of microcode development. If so, then please explain the use case and give a proper justification why this needs to be in the mainline kernel. Thanks, tglx