From nobody Wed Nov 5 12:20:51 2025 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.zohomail.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; dmarc=fail(p=none dis=none) header.from=redhat.com Return-Path: Received: from lists.gnu.org (lists.gnu.org [208.118.235.17]) by mx.zohomail.com with SMTPS id 1537460762226951.8150986083932; Thu, 20 Sep 2018 09:26:02 -0700 (PDT) Received: from localhost ([::1]:51973 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1g31mC-000136-Tn for importer@patchew.org; Thu, 20 Sep 2018 12:26:00 -0400 Received: from eggs.gnu.org ([2001:4830:134:3::10]:45764) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1g31h3-0004s8-OK for qemu-devel@nongnu.org; Thu, 20 Sep 2018 12:20:42 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1g31h2-0005rb-RW for qemu-devel@nongnu.org; Thu, 20 Sep 2018 12:20:41 -0400 Received: from mx1.redhat.com ([209.132.183.28]:16566) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1g31gx-0005nT-VA; Thu, 20 Sep 2018 12:20:36 -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 5AF4231524C5; Thu, 20 Sep 2018 16:20:35 +0000 (UTC) Received: from localhost.localdomain.com (ovpn-116-231.ams2.redhat.com [10.36.116.231]) by smtp.corp.redhat.com (Postfix) with ESMTP id 87D5285A39; Thu, 20 Sep 2018 16:20:33 +0000 (UTC) From: Kevin Wolf To: qemu-block@nongnu.org Date: Thu, 20 Sep 2018 18:19:50 +0200 Message-Id: <20180920161958.27453-12-kwolf@redhat.com> In-Reply-To: <20180920161958.27453-1-kwolf@redhat.com> References: <20180920161958.27453-1-kwolf@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 [10.5.110.41]); Thu, 20 Sep 2018 16:20:35 +0000 (UTC) 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] [PATCH v3 11/19] block-backend: Decrease in_flight only after callback 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: kwolf@redhat.com, famz@redhat.com, slp@redhat.com, qemu-devel@nongnu.org, mreitz@redhat.com, pbonzini@redhat.com, jsnow@redhat.com Errors-To: qemu-devel-bounces+importer=patchew.org@nongnu.org Sender: "Qemu-devel" X-ZohoMail: RDMRC_1 RSF_0 Z_629925259 SPT_0 Content-Transfer-Encoding: quoted-printable MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Request callbacks can do pretty much anything, including operations that will yield from the coroutine (such as draining the backend). In that case, a decreased in_flight would be visible to other code and could lead to a drain completing while the callback hasn't actually completed yet. Signed-off-by: Kevin Wolf Reviewed-by: Fam Zheng Reviewed-by: Max Reitz Reviewed-by: Paolo Bonzini --- block/block-backend.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/block/block-backend.c b/block/block-backend.c index 63eb2d10cd..5e5e60ff8d 100644 --- a/block/block-backend.c +++ b/block/block-backend.c @@ -1340,8 +1340,8 @@ static const AIOCBInfo blk_aio_em_aiocb_info =3D { static void blk_aio_complete(BlkAioEmAIOCB *acb) { if (acb->has_returned) { - blk_dec_in_flight(acb->rwco.blk); acb->common.cb(acb->common.opaque, acb->rwco.ret); + blk_dec_in_flight(acb->rwco.blk); qemu_aio_unref(acb); } } --=20 2.13.6