From patchwork Tue May 14 12:31:17 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Julien Grall X-Patchwork-Id: 10942959 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 29B2B1390 for ; Tue, 14 May 2019 12:32:53 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 191CC28701 for ; Tue, 14 May 2019 12:32:53 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 17370286A7; Tue, 14 May 2019 12:32:53 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-5.2 required=2.0 tests=BAYES_00,MAILING_LIST_MULTI, RCVD_IN_DNSWL_MED autolearn=ham version=3.3.1 Received: from lists.xenproject.org (lists.xenproject.org [192.237.175.120]) (using TLSv1.2 with cipher AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.wl.linuxfoundation.org (Postfix) with ESMTPS id BF69F2835B for ; Tue, 14 May 2019 12:32:52 +0000 (UTC) Received: from localhost ([127.0.0.1] helo=lists.xenproject.org) by lists.xenproject.org with esmtp (Exim 4.89) (envelope-from ) id 1hQWap-0005MA-9c; Tue, 14 May 2019 12:31:39 +0000 Received: from us1-rack-dfw2.inumbo.com ([104.130.134.6]) by lists.xenproject.org with esmtp (Exim 4.89) (envelope-from ) id 1hQWao-0005Le-0o for xen-devel@lists.xenproject.org; Tue, 14 May 2019 12:31:38 +0000 X-Inumbo-ID: 377b0a74-7644-11e9-8980-bc764e045a96 Received: from foss.arm.com (unknown [217.140.101.70]) by us1-rack-dfw2.inumbo.com (Halon) with ESMTP id 377b0a74-7644-11e9-8980-bc764e045a96; Tue, 14 May 2019 12:31:37 +0000 (UTC) Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.72.51.249]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id 1FBEB15AB; Tue, 14 May 2019 05:31:37 -0700 (PDT) Received: from e108454-lin.cambridge.arm.com (e108454-lin.cambridge.arm.com [10.1.196.50]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id E08DF3F71E; Tue, 14 May 2019 05:31:35 -0700 (PDT) From: Julien Grall To: xen-devel@lists.xenproject.org Date: Tue, 14 May 2019 13:31:17 +0100 Message-Id: <20190514123125.29086-5-julien.grall@arm.com> X-Mailer: git-send-email 2.11.0 In-Reply-To: <20190514123125.29086-1-julien.grall@arm.com> References: <20190514123125.29086-1-julien.grall@arm.com> Subject: [Xen-devel] [PATCH MM-PART3 v2 04/12] xen/arm: mm: Only increment mfn when valid in xen_pt_update 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: Oleksandr_Tyshchenko@epam.com, Julien Grall , Stefano Stabellini , Andrii Anisov MIME-Version: 1.0 Errors-To: xen-devel-bounces@lists.xenproject.org Sender: "Xen-devel" X-Virus-Scanned: ClamAV using ClamSMTP Currently, the MFN will be incremented even if it is invalid. This will result to have a valid MFN after the first iteration. While this is not a major problem today, this will be in the future if the code expect an invalid MFN at every iteration. Such behavior is prevented by avoiding to increment an invalid MFN. Signed-off-by: Julien Grall Reviewed-by: Andrii Anisov --- Changes in v2: - Move the patch earlier on in the series - Add Andrii's reviewed-by --- xen/arch/arm/mm.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) diff --git a/xen/arch/arm/mm.c b/xen/arch/arm/mm.c index f956aa6399..9de2a1150f 100644 --- a/xen/arch/arm/mm.c +++ b/xen/arch/arm/mm.c @@ -1051,11 +1051,14 @@ static int xen_pt_update(enum xenmap_operation op, spin_lock(&xen_pt_lock); - for(; addr < addr_end; addr += PAGE_SIZE, mfn = mfn_add(mfn, 1)) + for( ; addr < addr_end; addr += PAGE_SIZE ) { rc = xen_pt_update_entry(op, addr, mfn, flags); if ( rc ) break; + + if ( !mfn_eq(mfn, INVALID_MFN) ) + mfn = mfn_add(mfn, 1); } /*