From patchwork Fri Mar 17 06:14:47 2017 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Fam Zheng X-Patchwork-Id: 740175 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Received: from lists.gnu.org (lists.gnu.org [IPv6:2001:4830:134:3::11]) (using TLSv1 with cipher AES256-SHA (256/256 bits)) (No client certificate requested) by ozlabs.org (Postfix) with ESMTPS id 3vkw971bJpz9rxl for ; Fri, 17 Mar 2017 17:16:59 +1100 (AEDT) Received: from localhost ([::1]:47322 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1colC4-000796-Oe for incoming@patchwork.ozlabs.org; Fri, 17 Mar 2017 02:16:56 -0400 Received: from eggs.gnu.org ([2001:4830:134:3::10]:57608) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1colAA-0006Bf-Ih for qemu-devel@nongnu.org; Fri, 17 Mar 2017 02:14:59 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1colA8-00073f-SF for qemu-devel@nongnu.org; Fri, 17 Mar 2017 02:14:58 -0400 Received: from mx1.redhat.com ([209.132.183.28]:51228) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1colA8-00073Q-K5 for qemu-devel@nongnu.org; Fri, 17 Mar 2017 02:14:56 -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 AE49680460; Fri, 17 Mar 2017 06:14:56 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mx1.redhat.com AE49680460 Authentication-Results: ext-mx04.extmail.prod.ext.phx2.redhat.com; dmarc=none (p=none dis=none) header.from=redhat.com Authentication-Results: ext-mx04.extmail.prod.ext.phx2.redhat.com; spf=pass smtp.mailfrom=famz@redhat.com DKIM-Filter: OpenDKIM Filter v2.11.0 mx1.redhat.com AE49680460 Received: from lemon.redhat.com (ovpn-8-19.pek2.redhat.com [10.72.8.19]) by smtp.corp.redhat.com (Postfix) with ESMTP id 1C41C5DD62; Fri, 17 Mar 2017 06:14:54 +0000 (UTC) From: Fam Zheng To: qemu-devel@nongnu.org Date: Fri, 17 Mar 2017 14:14:47 +0800 Message-Id: <20170317061447.16243-3-famz@redhat.com> In-Reply-To: <20170317061447.16243-1-famz@redhat.com> References: <20170317061447.16243-1-famz@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 [10.5.110.28]); Fri, 17 Mar 2017 06:14:56 +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 v3 2/2] virtio-scsi: Fix acquire/release in 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 , Ed Swierk Errors-To: qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org Sender: "Qemu-devel" 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=none,id=root,format=raw,file=Fedora-Cloud-Base-25-1.3.x86_64.raw \ -device virtio-scsi \ -device scsi-disk,drive=root,bootindex=1 \ -object iothread,id=io \ -device virtio-scsi-pci,iothread=io \ -net user,hostfwd=tcp::10022-:22 -net nic,model=virtio -m 2048 \ --enable-kvm Fix this by moving acquire/release pairs from virtio_scsi_handle_*_vq to their callers - and wrap the broken assertions in. Signed-off-by: Fam Zheng --- hw/scsi/virtio-scsi-dataplane.c | 20 ++++++++++++++++---- hw/scsi/virtio-scsi.c | 27 ++++++++++++++------------- 2 files changed, 30 insertions(+), 17 deletions(-) diff --git a/hw/scsi/virtio-scsi-dataplane.c b/hw/scsi/virtio-scsi-dataplane.c index 74c95e0..944ea4e 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 = (VirtIOSCSI *)vdev; + bool progress; + VirtIOSCSI *s = VIRTIO_SCSI(vdev); + virtio_scsi_acquire(s); assert(s->ctx && s->dataplane_started); - return virtio_scsi_handle_cmd_vq(s, vq); + progress = virtio_scsi_handle_cmd_vq(s, vq); + virtio_scsi_release(s); + return progress; } static bool virtio_scsi_data_plane_handle_ctrl(VirtIODevice *vdev, VirtQueue *vq) { + bool progress; VirtIOSCSI *s = VIRTIO_SCSI(vdev); + virtio_scsi_acquire(s); assert(s->ctx && s->dataplane_started); - return virtio_scsi_handle_ctrl_vq(s, vq); + progress = virtio_scsi_handle_ctrl_vq(s, vq); + virtio_scsi_release(s); + return progress; } static bool virtio_scsi_data_plane_handle_event(VirtIODevice *vdev, VirtQueue *vq) { + bool progress; VirtIOSCSI *s = VIRTIO_SCSI(vdev); + virtio_scsi_acquire(s); assert(s->ctx && s->dataplane_started); - return virtio_scsi_handle_event_vq(s, vq); + progress = virtio_scsi_handle_event_vq(s, vq); + virtio_scsi_release(s); + return progress; } static int virtio_scsi_vring_init(VirtIOSCSI *s, VirtQueue *vq, int n, diff --git a/hw/scsi/virtio-scsi.c b/hw/scsi/virtio-scsi.c index e7466d3..bd62d08 100644 --- a/hw/scsi/virtio-scsi.c +++ b/hw/scsi/virtio-scsi.c @@ -427,12 +427,10 @@ bool virtio_scsi_handle_ctrl_vq(VirtIOSCSI *s, VirtQueue *vq) VirtIOSCSIReq *req; bool progress = false; - virtio_scsi_acquire(s); while ((req = virtio_scsi_pop_req(s, vq))) { progress = true; virtio_scsi_handle_ctrl_req(s, req); } - virtio_scsi_release(s); return progress; } @@ -446,7 +444,9 @@ static void virtio_scsi_handle_ctrl(VirtIODevice *vdev, VirtQueue *vq) return; } } + virtio_scsi_acquire(s); virtio_scsi_handle_ctrl_vq(s, vq); + virtio_scsi_release(s); } static void virtio_scsi_complete_cmd_req(VirtIOSCSIReq *req) @@ -590,7 +590,6 @@ bool virtio_scsi_handle_cmd_vq(VirtIOSCSI *s, VirtQueue *vq) QTAILQ_HEAD(, VirtIOSCSIReq) reqs = QTAILQ_HEAD_INITIALIZER(reqs); - virtio_scsi_acquire(s); do { virtio_queue_set_notification(vq, 0); @@ -618,7 +617,6 @@ bool virtio_scsi_handle_cmd_vq(VirtIOSCSI *s, VirtQueue *vq) QTAILQ_FOREACH_SAFE(req, &reqs, next, next) { virtio_scsi_handle_cmd_req_submit(s, req); } - virtio_scsi_release(s); return progress; } @@ -633,7 +631,9 @@ static void virtio_scsi_handle_cmd(VirtIODevice *vdev, VirtQueue *vq) return; } } + virtio_scsi_acquire(s); virtio_scsi_handle_cmd_vq(s, vq); + virtio_scsi_release(s); } static void virtio_scsi_get_config(VirtIODevice *vdev, @@ -709,12 +709,10 @@ void virtio_scsi_push_event(VirtIOSCSI *s, SCSIDevice *dev, return; } - virtio_scsi_acquire(s); - req = virtio_scsi_pop_req(s, vs->event_vq); if (!req) { s->events_dropped = true; - goto out; + return; } if (s->events_dropped) { @@ -724,7 +722,7 @@ void virtio_scsi_push_event(VirtIOSCSI *s, SCSIDevice *dev, if (virtio_scsi_parse_req(req, 0, sizeof(VirtIOSCSIEvent))) { virtio_scsi_bad_req(req); - goto out; + return; } evt = &req->resp.event; @@ -744,19 +742,14 @@ void virtio_scsi_push_event(VirtIOSCSI *s, SCSIDevice *dev, evt->lun[3] = dev->lun & 0xFF; } virtio_scsi_complete_req(req); -out: - virtio_scsi_release(s); } bool virtio_scsi_handle_event_vq(VirtIOSCSI *s, VirtQueue *vq) { - virtio_scsi_acquire(s); if (s->events_dropped) { virtio_scsi_push_event(s, NULL, VIRTIO_SCSI_T_NO_EVENT, 0); - virtio_scsi_release(s); return true; } - virtio_scsi_release(s); return false; } @@ -770,7 +763,9 @@ static void virtio_scsi_handle_event(VirtIODevice *vdev, VirtQueue *vq) return; } } + virtio_scsi_acquire(s); virtio_scsi_handle_event_vq(s, vq); + virtio_scsi_release(s); } static void virtio_scsi_change(SCSIBus *bus, SCSIDevice *dev, SCSISense sense) @@ -780,8 +775,10 @@ static void virtio_scsi_change(SCSIBus *bus, SCSIDevice *dev, SCSISense sense) if (virtio_vdev_has_feature(vdev, VIRTIO_SCSI_F_CHANGE) && dev->type != TYPE_ROM) { + virtio_scsi_acquire(s); virtio_scsi_push_event(s, dev, VIRTIO_SCSI_T_PARAM_CHANGE, sense.asc | (sense.ascq << 8)); + virtio_scsi_release(s); } } @@ -803,9 +800,11 @@ static void virtio_scsi_hotplug(HotplugHandler *hotplug_dev, DeviceState *dev, } if (virtio_vdev_has_feature(vdev, VIRTIO_SCSI_F_HOTPLUG)) { + virtio_scsi_acquire(s); virtio_scsi_push_event(s, sd, VIRTIO_SCSI_T_TRANSPORT_RESET, VIRTIO_SCSI_EVT_RESET_RESCAN); + virtio_scsi_release(s); } } @@ -817,9 +816,11 @@ static void virtio_scsi_hotunplug(HotplugHandler *hotplug_dev, DeviceState *dev, SCSIDevice *sd = SCSI_DEVICE(dev); if (virtio_vdev_has_feature(vdev, VIRTIO_SCSI_F_HOTPLUG)) { + virtio_scsi_acquire(s); virtio_scsi_push_event(s, sd, VIRTIO_SCSI_T_TRANSPORT_RESET, VIRTIO_SCSI_EVT_RESET_REMOVED); + virtio_scsi_release(s); } qdev_simple_device_unplug_cb(hotplug_dev, dev, errp);