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virtio-scsi: Fix acquire/release in dataplane handlers

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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 <famz@redhat.com>
Message-Id: <20170317061447.16243-3-famz@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
This commit is contained in:
Fam Zheng 2017-03-17 14:14:47 +08:00 committed by Paolo Bonzini
parent 3d69f82161
commit 7140778605
2 changed files with 30 additions and 17 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

20
hw/scsi/virtio-scsi-dataplane.c
View File

@ -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,

27
hw/scsi/virtio-scsi.c
View File

@ -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);