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=unavailable 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 03438C4332D for ; Fri, 20 Mar 2020 03:23:28 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id AA9FF20709 for ; Fri, 20 Mar 2020 03:23:27 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org AA9FF20709 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=arm.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=owner-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix) id DE6C46B0003; Thu, 19 Mar 2020 23:23:26 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id D96926B0006; Thu, 19 Mar 2020 23:23:26 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id CABF66B0007; Thu, 19 Mar 2020 23:23:26 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0238.hostedemail.com [216.40.44.238]) by kanga.kvack.org (Postfix) with ESMTP id B1CB66B0003 for ; Thu, 19 Mar 2020 23:23:26 -0400 (EDT) Received: from smtpin13.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay03.hostedemail.com (Postfix) with ESMTP id B75A0824556B for ; Fri, 20 Mar 2020 03:23:26 +0000 (UTC) X-FDA: 76614295212.13.nut04_583d15850670c X-HE-Tag: nut04_583d15850670c X-Filterd-Recvd-Size: 2819 Received: from foss.arm.com (foss.arm.com [217.140.110.172]) by imf46.hostedemail.com (Postfix) with ESMTP for ; Fri, 20 Mar 2020 03:23:26 +0000 (UTC) Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id 1AB811FB; Thu, 19 Mar 2020 20:23:25 -0700 (PDT) Received: from [10.163.1.20] (unknown [10.163.1.20]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id E8E883F85E; Thu, 19 Mar 2020 20:23:21 -0700 (PDT) Subject: Re: [PATCH] x86/mm: Make pud_present() check _PAGE_PROTNONE and _PAGE_PSE as well To: linux-mm@kvack.org Cc: Thomas Gleixner , Ingo Molnar , Borislav Petkov , "H. Peter Anvin" , Dave Hansen , Andrew Morton , x86@kernel.org, linux-kernel@vger.kernel.org, "Kirill A. Shutemov" , Dan Williams References: <1584507679-11976-1-git-send-email-anshuman.khandual@arm.com> From: Anshuman Khandual Message-ID: Date: Fri, 20 Mar 2020 08:53:16 +0530 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:52.0) Gecko/20100101 Thunderbird/52.9.1 MIME-Version: 1.0 In-Reply-To: <1584507679-11976-1-git-send-email-anshuman.khandual@arm.com> Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: On 03/18/2020 10:31 AM, Anshuman Khandual wrote: > pud_present() should also check _PAGE_PROTNONE and _PAGE_PSE bits like in > case pmd_present(). This makes a PUD entry test positive for pud_present() > after getting invalidated with pud_mknotpresent(), hence standardizing the > semantics with PMD helpers. > > Cc: Thomas Gleixner > Cc: Ingo Molnar > Cc: Borislav Petkov > Cc: "H. Peter Anvin" > Cc: Dave Hansen > Cc: Andrew Morton > Cc: x86@kernel.org > Cc: linux-mm@kvack.org > Cc: linux-kernel@vger.kernel.org > Signed-off-by: Anshuman Khandual > --- > Even though pud_mknotpresent() is not used any where currently, there is > a discrepancy between PMD and PUD. > > WARN_ON(!pud_present(pud_mknotpresent(pud_mkhuge(pud)))) -> Fail > WARN_ON(!pmd_present(pmd_mknotpresent(pmd_mkhuge(pmd)))) -> Pass > > Though pud_mknotpresent() currently clears _PAGE_PROTNONE, pud_present() > does not check it. This change fixes both inconsistencies. > > This has been build and boot tested on x86. Adding Kirill and Dan. +Cc: Kirill A. Shutemov +Cc: Dan Williams