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=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 17CF5C43613 for ; Thu, 20 Jun 2019 12:16:28 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id E351F2080C for ; Thu, 20 Jun 2019 12:16:27 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1731742AbfFTMQ0 (ORCPT ); Thu, 20 Jun 2019 08:16:26 -0400 Received: from mail-wm1-f65.google.com ([209.85.128.65]:54404 "EHLO mail-wm1-f65.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726874AbfFTMQ0 (ORCPT ); Thu, 20 Jun 2019 08:16:26 -0400 Received: by mail-wm1-f65.google.com with SMTP id g135so2838164wme.4 for ; Thu, 20 Jun 2019 05:16:25 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:subject:to:cc:references:from:message-id:date :user-agent:mime-version:in-reply-to:content-language :content-transfer-encoding; bh=B9TrtGyucT7ajjWuvboh+Hy5dvZksEd6/p4CR2fghIg=; b=A7OSdNT+3bcSy1ZMZkS3doXRRWmpmYpQeUp4St2vBpbna8fSIVmsIS9lt3WYKmo/lg EzqpP4JIPR+rDBwn9eIdfa+SHiOKztBxJTL+qk/5VKA61zYADlRMNjSmLBVDdYUJMUJW hR3Ab56kzX7q/jSBDFCLr+akM0jJT6uJUX1g/n9LQcS7ApENETP6hiGMkvpLvOnxxHhF aKEQkfHaScVzOcCnMBweJBXO/tLULzPh204es0YFpM5r6Doo03PJOat7njbaSWfwIgYq GuTn8myiIsNyCac1W5vhxEb/GzA1l4MdyBTH0TvXlhNZ7cPLIwP7U8IreDMcDNfBdUDY BP5A== X-Gm-Message-State: APjAAAWmsRlflUz647COptG6tYWdaOUpP3dH5VJp2SJOjOKxkFEf5uil CTrn//BWEMcoD6YKVsPgfc2H6A== X-Google-Smtp-Source: APXvYqzkWL+juoCKmAeAkp5CGN3y2wmBiY61EVn/WFlS6StZw7pwdzH2GmRBNiiSmutGjpGYKskLFA== X-Received: by 2002:a1c:4484:: with SMTP id r126mr2782080wma.27.1561032984421; Thu, 20 Jun 2019 05:16:24 -0700 (PDT) Received: from ?IPv6:2001:b07:6468:f312:7822:aa18:a9d8:39ab? ([2001:b07:6468:f312:7822:aa18:a9d8:39ab]) by smtp.gmail.com with ESMTPSA id d18sm36464286wrb.90.2019.06.20.05.16.23 (version=TLS1_3 cipher=AEAD-AES128-GCM-SHA256 bits=128/128); Thu, 20 Jun 2019 05:16:23 -0700 (PDT) Subject: Re: [PATCH RFC] kvm: x86: Expose AVX512_BF16 feature to guest To: Jing Liu , kvm@vger.kernel.org Cc: linux-kernel@vger.kernel.org, jing2.liu@intel.com References: <1561029712-11848-1-git-send-email-jing2.liu@linux.intel.com> <1561029712-11848-2-git-send-email-jing2.liu@linux.intel.com> From: Paolo Bonzini Message-ID: Date: Thu, 20 Jun 2019 14:16:22 +0200 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:60.0) Gecko/20100101 Thunderbird/60.6.1 MIME-Version: 1.0 In-Reply-To: <1561029712-11848-2-git-send-email-jing2.liu@linux.intel.com> Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 20/06/19 13:21, Jing Liu wrote: > + for (i = 1; i <= times; i++) { > + if (*nent >= maxnent) > + goto out; > + do_cpuid_1_ent(&entry[i], function, i); > + entry[i].eax &= F(AVX512_BF16); > + entry[i].ebx = 0; > + entry[i].ecx = 0; > + entry[i].edx = 0; > + entry[i].flags |= KVM_CPUID_FLAG_SIGNIFCANT_INDEX; > + ++*nent; This woud be wrong for i > 1, so instead make this if (entry->eax >= 1) and define F(AVX512_BF16) as a new constant kvm_cpuid_7_1_eax_features. Paolo