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=-6.7 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED 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 50EAAC3A59C for ; Fri, 16 Aug 2019 09:44:17 +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 28DE620644 for ; Fri, 16 Aug 2019 09:44:17 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 28DE620644 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]:52562 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1hyYmO-0001u1-1S for qemu-devel@archiver.kernel.org; Fri, 16 Aug 2019 05:44:16 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:59643) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1hyYdV-0000BK-TU for qemu-devel@nongnu.org; Fri, 16 Aug 2019 05:35:06 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1hyYdU-0003rn-MN for qemu-devel@nongnu.org; Fri, 16 Aug 2019 05:35:05 -0400 Received: from mx1.redhat.com ([209.132.183.28]:56350) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1hyYdS-0003og-DK; Fri, 16 Aug 2019 05:35:02 -0400 Received: from smtp.corp.redhat.com (int-mx06.intmail.prod.int.phx2.redhat.com [10.5.11.16]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id AFCA2306046D; Fri, 16 Aug 2019 09:35:01 +0000 (UTC) Received: from localhost.localdomain.com (dhcp-200-226.str.redhat.com [10.33.200.226]) by smtp.corp.redhat.com (Postfix) with ESMTP id DC63B5C1D6; Fri, 16 Aug 2019 09:34:58 +0000 (UTC) From: Kevin Wolf To: qemu-block@nongnu.org Date: Fri, 16 Aug 2019 11:34:36 +0200 Message-Id: <20190816093439.14262-14-kwolf@redhat.com> In-Reply-To: <20190816093439.14262-1-kwolf@redhat.com> References: <20190816093439.14262-1-kwolf@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.16 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.41]); Fri, 16 Aug 2019 09:35:01 +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 13/16] mirror: Keep mirror_top_bs drained after dropping permissions 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, qemu-devel@nongnu.org Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" mirror_top_bs is currently implicitly drained through its connection to the source or the target node. However, the drain section for target_bs ends early after moving mirror_top_bs from src to target_bs, so that requests can already be restarted while mirror_top_bs is still present in the chain, but has dropped all permissions and therefore runs into an assertion failure like this: qemu-system-x86_64: block/io.c:1634: bdrv_co_write_req_prepare: Assertion `child->perm & BLK_PERM_WRITE' failed. Keep mirror_top_bs drained until all graph changes have completed. Cc: qemu-stable@nongnu.org Signed-off-by: Kevin Wolf Reviewed-by: Max Reitz --- block/mirror.c | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-) diff --git a/block/mirror.c b/block/mirror.c index 9f5c59ece1..642d6570cc 100644 --- a/block/mirror.c +++ b/block/mirror.c @@ -656,7 +656,10 @@ static int mirror_exit_common(Job *job) s->target =3D NULL; =20 /* We don't access the source any more. Dropping any WRITE/RESIZE is - * required before it could become a backing file of target_bs. */ + * required before it could become a backing file of target_bs. Not = having + * these permissions any more means that we can't allow any new requ= ests on + * mirror_top_bs from now on, so keep it drained. */ + bdrv_drained_begin(mirror_top_bs); bs_opaque->stop =3D true; bdrv_child_refresh_perms(mirror_top_bs, mirror_top_bs->backing, &error_abort); @@ -724,6 +727,7 @@ static int mirror_exit_common(Job *job) bs_opaque->job =3D NULL; =20 bdrv_drained_end(src); + bdrv_drained_end(mirror_top_bs); s->in_drain =3D false; bdrv_unref(mirror_top_bs); bdrv_unref(src); --=20 2.20.1