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=-6.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS autolearn=ham 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 C82E5C0650F for ; Tue, 30 Jul 2019 11:26:57 +0000 (UTC) Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id A0ED32087F for ; Tue, 30 Jul 2019 11:26:57 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org A0ED32087F Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=redhat.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Received: from localhost ([::1]:59848 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.86_2) (envelope-from ) id 1hsQHQ-0007YK-QK for qemu-devel@archiver.kernel.org; Tue, 30 Jul 2019 07:26:56 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:52252) by lists.gnu.org with esmtp (Exim 4.86_2) (envelope-from ) id 1hsQFJ-0003am-DH for qemu-devel@nongnu.org; Tue, 30 Jul 2019 07:24:46 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1hsQFH-0006jd-Hq for qemu-devel@nongnu.org; Tue, 30 Jul 2019 07:24:44 -0400 Received: from mx1.redhat.com ([209.132.183.28]:43288) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1hsQF8-0006eH-FU; Tue, 30 Jul 2019 07:24:35 -0400 Received: from smtp.corp.redhat.com (int-mx03.intmail.prod.int.phx2.redhat.com [10.5.11.13]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id C3D6B88313; Tue, 30 Jul 2019 11:24:33 +0000 (UTC) Received: from localhost.localdomain.com (ovpn-117-75.ams2.redhat.com [10.36.117.75]) by smtp.corp.redhat.com (Postfix) with ESMTP id B9BB260623; Tue, 30 Jul 2019 11:24:32 +0000 (UTC) From: Kevin Wolf To: qemu-block@nongnu.org Date: Tue, 30 Jul 2019 13:24:24 +0200 Message-Id: <20190730112425.21497-4-kwolf@redhat.com> In-Reply-To: <20190730112425.21497-1-kwolf@redhat.com> References: <20190730112425.21497-1-kwolf@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.13 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.28]); Tue, 30 Jul 2019 11:24:33 +0000 (UTC) Content-Transfer-Encoding: quoted-printable X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.2.x-3.x [generic] X-Received-From: 209.132.183.28 Subject: [Qemu-devel] [PULL 3/4] block/copy-on-read: Fix permissions for inactive node X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.23 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: kwolf@redhat.com, peter.maydell@linaro.org, qemu-devel@nongnu.org Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" The copy-on-read drive must not request the WRITE_UNCHANGED permission for its child if the node is inactive, otherwise starting a migration destination with -incoming will fail because the child cannot provide write access yet: qemu-system-x86_64: -blockdev copy-on-read,file=3Dimg,node-name=3Dcor: = Block node is read-only Earlier QEMU versions additionally ran into an abort() on the migration source side: bdrv_inactivate_recurse() failed to update permissions. This is silently ignored today because it was only supposed to loosen restrictions. This is the symptom that was originally reported here: https://bugzilla.redhat.com/show_bug.cgi?id=3D1733022 Signed-off-by: Kevin Wolf Reviewed-by: Max Reitz --- block/copy-on-read.c | 16 +++++++--------- 1 file changed, 7 insertions(+), 9 deletions(-) diff --git a/block/copy-on-read.c b/block/copy-on-read.c index 22f24fd0db..6631f30205 100644 --- a/block/copy-on-read.c +++ b/block/copy-on-read.c @@ -56,16 +56,14 @@ static void cor_child_perm(BlockDriverState *bs, Bdrv= Child *c, uint64_t perm, uint64_t shared, uint64_t *nperm, uint64_t *nshared) { - if (c =3D=3D NULL) { - *nperm =3D (perm & PERM_PASSTHROUGH) | BLK_PERM_WRITE_UNCHANGED; - *nshared =3D (shared & PERM_PASSTHROUGH) | PERM_UNCHANGED; - return; - } + *nperm =3D perm & PERM_PASSTHROUGH; + *nshared =3D (shared & PERM_PASSTHROUGH) | PERM_UNCHANGED; =20 - *nperm =3D (perm & PERM_PASSTHROUGH) | - (c->perm & PERM_UNCHANGED); - *nshared =3D (shared & PERM_PASSTHROUGH) | - (c->shared_perm & PERM_UNCHANGED); + /* We must not request write permissions for an inactive node, the c= hild + * cannot provide it. */ + if (!(bs->open_flags & BDRV_O_INACTIVE)) { + *nperm |=3D BLK_PERM_WRITE_UNCHANGED; + } } =20 =20 --=20 2.20.1