From nobody Thu May 2 13:34:14 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 1489498051712604.1137175500435; Tue, 14 Mar 2017 06:27:31 -0700 (PDT) Received: from localhost ([::1]:59505 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1cnmU5-0004RY-Ho for importer@patchew.org; Tue, 14 Mar 2017 09:27:29 -0400 Received: from eggs.gnu.org ([2001:4830:134:3::10]:57589) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1cnmTe-0004RO-3j for qemu-devel@nongnu.org; Tue, 14 Mar 2017 09:27:03 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1cnmTa-0006Bk-SS for qemu-devel@nongnu.org; Tue, 14 Mar 2017 09:27:02 -0400 Received: from mx1.redhat.com ([209.132.183.28]:48198) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1cnmTa-0006BI-Mg for qemu-devel@nongnu.org; Tue, 14 Mar 2017 09:26:58 -0400 Received: from int-mx14.intmail.prod.int.phx2.redhat.com (int-mx14.intmail.prod.int.phx2.redhat.com [10.5.11.27]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id DC1B93D941 for ; Tue, 14 Mar 2017 13:26:58 +0000 (UTC) Received: from lemon.redhat.com (ovpn-8-40.pek2.redhat.com [10.72.8.40]) by int-mx14.intmail.prod.int.phx2.redhat.com (8.14.4/8.14.4) with ESMTP id v2EDQu2c015278; Tue, 14 Mar 2017 09:26:57 -0400 From: Fam Zheng To: qemu-devel@nongnu.org Date: Tue, 14 Mar 2017 21:26:54 +0800 Message-Id: <20170314132654.6751-1-famz@redhat.com> X-Scanned-By: MIMEDefang 2.68 on 10.5.11.27 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.30]); Tue, 14 Mar 2017 13:26:58 +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 for-2.9] virtio-scsi: Fix assertion failure on dataplane handlers 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 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" After the AioContext lock push down, there is a race between virtio_scsi_dataplane_start and those "assert(s->ctx && s->dataplane_started)", because the latter doesn't isn't wrapped in aio_context_acquire. Reproducer is simply booting a Fedora guest with an empty virtio-scsi-dataplane controller: qemu-system-x86_64 \ -drive if=3Dnone,id=3Droot,format=3Draw,file=3DFedora-Cloud-Base-25-1= .3.x86_64.raw \ -device virtio-scsi \ -device scsi-disk,drive=3Droot,bootindex=3D1 \ -object iothread,id=3Dio \ -device virtio-scsi-pci,iothread=3Dio \ -net user,hostfwd=3Dtcp::10022-:22 -net nic,model=3Dvirtio -m 2048 \ --enable-kvm Signed-off-by: Fam Zheng --- hw/scsi/virtio-scsi-dataplane.c | 20 ++++++++++++++++---- 1 file changed, 16 insertions(+), 4 deletions(-) diff --git a/hw/scsi/virtio-scsi-dataplane.c b/hw/scsi/virtio-scsi-dataplan= e.c index 74c95e0..12b44b7 100644 --- a/hw/scsi/virtio-scsi-dataplane.c +++ b/hw/scsi/virtio-scsi-dataplane.c @@ -52,28 +52,40 @@ void virtio_scsi_dataplane_setup(VirtIOSCSI *s, Error *= *errp) static bool virtio_scsi_data_plane_handle_cmd(VirtIODevice *vdev, VirtQueue *vq) { - VirtIOSCSI *s =3D (VirtIOSCSI *)vdev; + bool progress; + VirtIOSCSI *s =3D VIRTIO_SCSI(vdev); =20 + aio_context_acquire(s->ctx); assert(s->ctx && s->dataplane_started); - return virtio_scsi_handle_cmd_vq(s, vq); + progress =3D virtio_scsi_handle_cmd_vq(s, vq); + aio_context_release(s->ctx); + return progress; } =20 static bool virtio_scsi_data_plane_handle_ctrl(VirtIODevice *vdev, VirtQueue *vq) { + bool progress; VirtIOSCSI *s =3D VIRTIO_SCSI(vdev); =20 + aio_context_acquire(s->ctx); assert(s->ctx && s->dataplane_started); - return virtio_scsi_handle_ctrl_vq(s, vq); + progress =3D virtio_scsi_handle_ctrl_vq(s, vq); + aio_context_release(s->ctx); + return progress; } =20 static bool virtio_scsi_data_plane_handle_event(VirtIODevice *vdev, VirtQueue *vq) { + bool progress; VirtIOSCSI *s =3D VIRTIO_SCSI(vdev); =20 + aio_context_acquire(s->ctx); assert(s->ctx && s->dataplane_started); - return virtio_scsi_handle_event_vq(s, vq); + progress =3D virtio_scsi_handle_event_vq(s, vq); + aio_context_release(s->ctx); + return progress; } =20 static int virtio_scsi_vring_init(VirtIOSCSI *s, VirtQueue *vq, int n, --=20 2.9.3