From nobody Tue Apr 30 14:03:00 2024 Delivered-To: importer@patchew.org Received-SPF: pass (zoho.com: domain of gnu.org designates 208.118.235.17 as permitted sender) client-ip=208.118.235.17; envelope-from=qemu-devel-bounces+importer=patchew.org@nongnu.org; helo=lists.gnu.org; Authentication-Results: mx.zoho.com; spf=pass (zoho.com: domain of gnu.org designates 208.118.235.17 as permitted sender) smtp.mailfrom=qemu-devel-bounces+importer=patchew.org@nongnu.org; Return-Path: Received: from lists.gnu.org (lists.gnu.org [208.118.235.17]) by mx.zohomail.com with SMTPS id 1496212537040738.4032761291392; Tue, 30 May 2017 23:35:37 -0700 (PDT) Received: from localhost ([::1]:57560 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1dFxEF-0007Ik-LB for importer@patchew.org; Wed, 31 May 2017 02:35:35 -0400 Received: from eggs.gnu.org ([2001:4830:134:3::10]:55180) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1dFxBx-0005nH-7K for qemu-devel@nongnu.org; Wed, 31 May 2017 02:33:14 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1dFxBt-0004Ul-B1 for qemu-devel@nongnu.org; Wed, 31 May 2017 02:33:13 -0400 Received: from mx1.redhat.com ([209.132.183.28]:44074) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1dFxBt-0004TK-5y for qemu-devel@nongnu.org; Wed, 31 May 2017 02:33:09 -0400 Received: from smtp.corp.redhat.com (int-mx04.intmail.prod.int.phx2.redhat.com [10.5.11.14]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id 285A94E4CD for ; Wed, 31 May 2017 06:33:08 +0000 (UTC) Received: from pxdev.xzpeter.org.com (ovpn-12-112.pek2.redhat.com [10.72.12.112]) by smtp.corp.redhat.com (Postfix) with ESMTP id C76381867E; Wed, 31 May 2017 06:33:02 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mx1.redhat.com 285A94E4CD Authentication-Results: ext-mx09.extmail.prod.ext.phx2.redhat.com; dmarc=none (p=none dis=none) header.from=redhat.com Authentication-Results: ext-mx09.extmail.prod.ext.phx2.redhat.com; spf=pass smtp.mailfrom=peterx@redhat.com DKIM-Filter: OpenDKIM Filter v2.11.0 mx1.redhat.com 285A94E4CD From: Peter Xu To: qemu-devel@nongnu.org Date: Wed, 31 May 2017 14:32:58 +0800 Message-Id: <1496212378-22605-1-git-send-email-peterx@redhat.com> X-Scanned-By: MIMEDefang 2.79 on 10.5.11.14 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.38]); Wed, 31 May 2017 06:33:08 +0000 (UTC) X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.2.x-3.x [generic] [fuzzy] X-Received-From: 209.132.183.28 Subject: [Qemu-devel] [PATCH v3] exec: fix address_space_get_iotlb_entry page mask X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.21 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Paolo Bonzini , Maxime Coquelin , peterx@redhat.com Errors-To: qemu-devel-bounces+importer=patchew.org@nongnu.org Sender: "Qemu-devel" X-ZohoMail: RSF_0 Z_629925259 SPT_0 Content-Transfer-Encoding: quoted-printable MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" The IOTLB that it returned didn't guarantee that page_mask is indeed a so-called page mask. That won't affect current usage since now only vhost is using it (vhost API allows arbitary IOTLB range). However we have IOTLB scemantic and we should best follow it. This patch fixes this issue to make sure the page_mask is always a valid page mask. Fixes: a764040 ("exec: abstract address_space_do_translate()") Signed-off-by: Peter Xu --- v3: - use pow2floor() [Paolo] --- exec.c | 14 ++++++-------- 1 file changed, 6 insertions(+), 8 deletions(-) diff --git a/exec.c b/exec.c index b1db12f..8fc0e78 100644 --- a/exec.c +++ b/exec.c @@ -530,16 +530,14 @@ IOMMUTLBEntry address_space_get_iotlb_entry(AddressSp= ace *as, hwaddr addr, section.offset_within_region; =20 if (plen =3D=3D (hwaddr)-1) { - /* - * We use default page size here. Logically it only happens - * for identity mappings. - */ - plen =3D TARGET_PAGE_SIZE; + /* If not specified during translation, use default mask */ + plen =3D TARGET_PAGE_MASK; + } else { + /* Make it a valid page mask */ + assert(plen); + plen =3D pow2floor(plen) - 1; } =20 - /* Convert to address mask */ - plen -=3D 1; - return (IOMMUTLBEntry) { .target_as =3D section.address_space, .iova =3D addr & ~plen, --=20 2.7.4