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=-5.3 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_1 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 97461C43331 for ; Tue, 31 Mar 2020 14:37:15 +0000 (UTC) Received: from lists.xenproject.org (lists.xenproject.org [192.237.175.120]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 701802071A for ; Tue, 31 Mar 2020 14:37:15 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 701802071A Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=suse.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=xen-devel-bounces@lists.xenproject.org Received: from localhost ([127.0.0.1] helo=lists.xenproject.org) by lists.xenproject.org with esmtp (Exim 4.89) (envelope-from ) id 1jJI0f-0007Ka-Py; Tue, 31 Mar 2020 14:36:57 +0000 Received: from us1-rack-iad1.inumbo.com ([172.99.69.81]) by lists.xenproject.org with esmtp (Exim 4.89) (envelope-from ) id 1jJI0e-0007KV-C6 for xen-devel@lists.xenproject.org; Tue, 31 Mar 2020 14:36:56 +0000 X-Inumbo-ID: 11a5cbb6-735d-11ea-b4f4-bc764e2007e4 Received: from mx2.suse.de (unknown [195.135.220.15]) by us1-rack-iad1.inumbo.com (Halon) with ESMTPS id 11a5cbb6-735d-11ea-b4f4-bc764e2007e4; Tue, 31 Mar 2020 14:36:55 +0000 (UTC) X-Virus-Scanned: by amavisd-new at test-mx.suse.de Received: from relay2.suse.de (unknown [195.135.220.254]) by mx2.suse.de (Postfix) with ESMTP id EC37BAF1D; Tue, 31 Mar 2020 14:36:54 +0000 (UTC) Subject: Re: [PATCH 05/11] x86/ucode/amd: Overhaul the equivalent cpu table handling completely To: Andrew Cooper References: <20200331100531.4294-1-andrew.cooper3@citrix.com> <20200331100531.4294-6-andrew.cooper3@citrix.com> From: Jan Beulich Message-ID: <53fe152f-c503-ba1f-a64b-d6685ea018fd@suse.com> Date: Tue, 31 Mar 2020 16:36:52 +0200 User-Agent: Mozilla/5.0 (Windows NT 10.0; WOW64; rv:68.0) Gecko/20100101 Thunderbird/68.6.0 MIME-Version: 1.0 In-Reply-To: <20200331100531.4294-6-andrew.cooper3@citrix.com> Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit X-BeenThere: xen-devel@lists.xenproject.org X-Mailman-Version: 2.1.23 Precedence: list List-Id: Xen developer discussion List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Cc: Xen-devel , Wei Liu , =?UTF-8?Q?Roger_Pau_Monn=c3=a9?= Errors-To: xen-devel-bounces@lists.xenproject.org Sender: "Xen-devel" On 31.03.2020 12:05, Andrew Cooper wrote: > We currently copy the entire equivalency table, and the single correct > microcode. This is not safe to heterogeneous scenarios, and as Xen doesn't > support such situations to being with, can be used to simplify things further. s/being/begin/ ? > The CPUID.1.EAX => processor_rev_id mapping is fixed for an individual part. > We can cache the single appropriate entry on first discovery, and forgo > duplicating the entire table. > > Alter install_equiv_cpu_table() to be scan_equiv_cpu_table() which is > responsible for checking the equivalency table and caching appropriate > details. It now has a check for finding a different mapping (which indicates > that one of the tables we've seen is definitely wrong). > > A return value of -ESRCH is now used to signify "everything fine, but nothing > applicable for the current CPU", which is used to select the > container_fast_forward() path. > > Drop the printk(), as each applicable error path in scan_equiv_cpu_table() > already prints diagnostics. > > Signed-off-by: Andrew Cooper Reviewed-by: Jan Beulich