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=-5.9 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,NICE_REPLY_A,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 C529EC433DF for ; Mon, 17 Aug 2020 18:56:43 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id A04572072E for ; Mon, 17 Aug 2020 18:56:43 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="Q/hsqM8I" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1731750AbgHQS4k (ORCPT ); Mon, 17 Aug 2020 14:56:40 -0400 Received: from us-smtp-2.mimecast.com ([205.139.110.61]:44570 "EHLO us-smtp-delivery-1.mimecast.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1731467AbgHQS42 (ORCPT ); Mon, 17 Aug 2020 14:56:28 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1597690585; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=P+SWVW+pjg81S9WWqotQ3smvkOJqzR+CExLaQMZK0Pw=; b=Q/hsqM8I1IA1A2Csj8E/CJWcCySYokbi0wnDz4vVjX7E2sELmz+D/v38jTOu6NpFPTl6pw +Dsl++ULV1dc1WSoAzHbNHxmIuWR1SpFVN4ylqR5qLWRzOWgvrRfAnq5Uvz2M2dmfeo10t XF7UYGArExM3gghVBStvbB6zK9q6HLg= Received: from mail-wr1-f72.google.com (mail-wr1-f72.google.com [209.85.221.72]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-222-0cPwofDoP4WTQ4hZHAIp8w-1; Mon, 17 Aug 2020 14:56:23 -0400 X-MC-Unique: 0cPwofDoP4WTQ4hZHAIp8w-1 Received: by mail-wr1-f72.google.com with SMTP id 89so7372274wrr.15 for ; Mon, 17 Aug 2020 11:56:23 -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=P+SWVW+pjg81S9WWqotQ3smvkOJqzR+CExLaQMZK0Pw=; b=C92iEX5AX4c4BooKs/zda9+lgNKBMIjuT9nB+mqI3DETA+J5yiEvMcWnZ8HLI46EON nlzwHYWA/TxJS/aIF8j4/qG3PXiww0YVeFJUOqkF69sXtTmFayChIKeZDCIUbwwQW/lK VthK7VK3UEz9wuBlHv9s99tLn/CwO6b2e/G9fMu4z949LbhzRyLe8bRiFHnhU7Kx9iiA y+aepSFz6V/H6FLuBaj9SrWBH2Y2fN8mPQW9ra/2EgnEHslpIZ1pm5MKlJ15qerVv39k y2nhC6/RogIJW/tqhwrSwpjtUr5ejjbMmLZRNzPpTJ7gG0kljFuD01XAcb/z+S7y0qBo MjaQ== X-Gm-Message-State: AOAM5337wWTDlfydgbGYvUqXATSQKi9P/YWLriHJFLppqvDjIN+ZFKGX OvE7fb9SlamvCbGz2VGhoRsOQubzLuEwszxCUy9uxLcsElfG54A4Mpjh6+D9dk5CFhTAtOdwM64 UwYlI1y7revX6EUJSJRzVR2Es X-Received: by 2002:a1c:7705:: with SMTP id t5mr16436381wmi.112.1597690582493; Mon, 17 Aug 2020 11:56:22 -0700 (PDT) X-Google-Smtp-Source: ABdhPJxV6kFCk0mELAK5UYZBHElUrR6OjmsPsIgsjsuvWmke05COroSNIAs3VHHaBHPOCPA2bimU5A== X-Received: by 2002:a1c:7705:: with SMTP id t5mr16436367wmi.112.1597690582208; Mon, 17 Aug 2020 11:56:22 -0700 (PDT) Received: from ?IPv6:2001:b07:6468:f312:a0d1:fc42:c610:f977? ([2001:b07:6468:f312:a0d1:fc42:c610:f977]) by smtp.gmail.com with ESMTPSA id r3sm29893163wro.1.2020.08.17.11.56.21 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Mon, 17 Aug 2020 11:56:21 -0700 (PDT) Subject: Re: [PATCH] KVM: x86: fix access code passed to gva_to_gpa To: Sean Christopherson Cc: linux-kernel@vger.kernel.org, kvm@vger.kernel.org References: <20200817180042.32264-1-pbonzini@redhat.com> <20200817184226.GJ22407@linux.intel.com> From: Paolo Bonzini Message-ID: <77e46758-4b00-9db9-13ab-329c6dad66f3@redhat.com> Date: Mon, 17 Aug 2020 20:56:20 +0200 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:68.0) Gecko/20100101 Thunderbird/68.9.0 MIME-Version: 1.0 In-Reply-To: <20200817184226.GJ22407@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 17/08/20 20:42, Sean Christopherson wrote: > > Don't suppose you'd be in the mood to kill the bare 'unsigned'? > > WARNING: Prefer 'unsigned int' to bare use of 'unsigned' u32 is even better. > Alternatively, what about capturing the result in a new variable (instead of > defining the mask) to make the wrap suck less (or just overflow like the > current code), e.g.: > > u32 access = error_code & > (PFERR_WRITE_MASK | PFERR_FETCH_MASK | PFERR_USER_MASK); > > if (!(error_code & PFERR_PRESENT_MASK) || > vcpu->arch.walk_mmu->gva_to_gpa(vcpu, gva, access, &fault) != UNMAPPED_GVA) { Sure, that's better. Paolo