From patchwork Wed Apr 24 16:59:48 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Julien Grall X-Patchwork-Id: 10915279 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 D15CC922 for ; Wed, 24 Apr 2019 17:02:24 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id BFD9128B3E for ; Wed, 24 Apr 2019 17:02:24 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id B4A2528B81; Wed, 24 Apr 2019 17:02:24 +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 6A52828B3E for ; Wed, 24 Apr 2019 17:02:24 +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 1hJLFl-0007nY-9o; Wed, 24 Apr 2019 17:00:13 +0000 Received: from all-amaz-eas1.inumbo.com ([34.197.232.57] helo=us1-amaz-eas2.inumbo.com) by lists.xenproject.org with esmtp (Exim 4.89) (envelope-from ) id 1hJLFk-0007nN-9Z for xen-devel@lists.xenproject.org; Wed, 24 Apr 2019 17:00:12 +0000 X-Inumbo-ID: 6c1ccaee-66b2-11e9-ace0-d3443eb28cba Received: from foss.arm.com (unknown [217.140.101.70]) by us1-amaz-eas2.inumbo.com (Halon) with ESMTP id 6c1ccaee-66b2-11e9-ace0-d3443eb28cba; Wed, 24 Apr 2019 17:00:11 +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 5A9E115BE; Wed, 24 Apr 2019 10:00:11 -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 3FD433F557; Wed, 24 Apr 2019 10:00:10 -0700 (PDT) From: Julien Grall To: xen-devel@lists.xenproject.org Date: Wed, 24 Apr 2019 17:59:48 +0100 Message-Id: <20190424165955.23718-6-julien.grall@arm.com> X-Mailer: git-send-email 2.11.0 In-Reply-To: <20190424165955.23718-1-julien.grall@arm.com> References: <20190424165955.23718-1-julien.grall@arm.com> Subject: [Xen-devel] [PATCH 05/12] 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 , sstabellini@kernel.org, Andrii_Anisov@epam.com 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 --- 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 b61217abd0..eee7122c88 100644 --- a/xen/arch/arm/mm.c +++ b/xen/arch/arm/mm.c @@ -1046,11 +1046,14 @@ 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); } /*