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_PASS autolearn=ham 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 A79A1C67871 for ; Sat, 6 Oct 2018 16:11:23 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 784722089D for ; Sat, 6 Oct 2018 16:11:23 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 784722089D Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=linutronix.de Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727836AbeJFXPP (ORCPT ); Sat, 6 Oct 2018 19:15:15 -0400 Received: from Galois.linutronix.de ([146.0.238.70]:39448 "EHLO Galois.linutronix.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725266AbeJFXPP (ORCPT ); Sat, 6 Oct 2018 19:15:15 -0400 Received: from p5492e4c1.dip0.t-ipconnect.de ([84.146.228.193] helo=nanos) by Galois.linutronix.de with esmtpsa (TLS1.2:DHE_RSA_AES_256_CBC_SHA256:256) (Exim 4.80) (envelope-from ) id 1g8pAP-0006rF-UO; Sat, 06 Oct 2018 18:10:58 +0200 Date: Sat, 6 Oct 2018 18:10:57 +0200 (CEST) From: Thomas Gleixner To: Andi Kleen cc: peterz@infradead.org, x86@kernel.org, linux-kernel@vger.kernel.org, eranian@google.com, kan.liang@intel.com, isaku.yamahata@intel.com, kvm@vger.kernel.org, Andi Kleen Subject: Re: [PATCH v1 1/2] x86/cpufeature: Add facility to match microcode revisions In-Reply-To: Message-ID: References: <20181006001928.28097-1-andi@firstfloor.org> 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 Sat, 6 Oct 2018, Thomas Gleixner wrote: > On Fri, 5 Oct 2018, Andi Kleen wrote: > > +/* > > + * Match specific microcodes or steppings. > > What means microcodes or steppings? If you mean microcode revisions then > please spell it out and use it all over the place. steppings is confusing > at best as its associated to the CPU stepping. > > > + * > > + * vendor/family/model/stepping must be all set. > > + * min_ucode/max_ucode/driver_data are optional and can be 0. > > + */ > > + > > +struct x86_ucode_id { > > + __u16 vendor; > > __uXX are usually UAPI types. Please use the regular kernel uXX > types instead. > > > + __u16 family; > > + __u16 model; > > + __u16 stepping; > > Why u16? The corresponding members in cpuinfo_x86 are 8bit wide so why > wasting memory for these tables? > > > + __u32 min_ucode; > > + __u32 max_ucode; > > + kernel_ulong_t driver_data; Why do we need max_ucode and driver_data? I can't find an existing example where this would be useful. If we need it later then it can be added incrementaly. Thanks, tglx