vhost: fix vring address handling during live migration

When live migration starts, QEMU will set ring addrs again for
each virtqueue. In this case, we should try to translate ring
addrs after we invalidating the ring, otherwise virtqueues can
be enabled with the addrs untranslated. Besides, also leverage
the access_ok flag in non-IOMMU case to prevent the data path
accessing invalidated virtqueues.

Fixes: 5a4933e56be4 ("vhost: postpone ring address translations at kick time only")
Cc: stable@dpdk.org
Reported-by: Yilong Lv <lvyilong.lyl@alibaba-inc.com>
Signed-off-by: Tiwei Bie <tiwei.bie@intel.com>
Reviewed-by: Maxime Coquelin <maxime.coquelin@redhat.com>

diff --git a/lib/librte_vhost/vhost.c b/lib/librte_vhost/vhost.c
index 981837b5dde037eb6a1d9017d5a49eee1f9d3e5d..77be160697b2faedfafb8356f3d9807f5ed2d9a3 100644 (file)
--- a/lib/librte_vhost/vhost.c
+++ b/lib/librte_vhost/vhost.c
@@ -358,7 +358,7 @@ vring_translate(struct virtio_net *dev, struct vhost_virtqueue *vq)
 {
 
        if (!(dev->features & (1ULL << VIRTIO_F_IOMMU_PLATFORM)))
-               goto out;
+               return -1;
 
        if (vq_is_packed(dev)) {
                if (vring_translate_packed(dev, vq) < 0)
@@ -367,7 +367,6 @@ vring_translate(struct virtio_net *dev, struct vhost_virtqueue *vq)
                if (vring_translate_split(dev, vq) < 0)
                        return -1;
        }
-out:
        vq->access_ok = 1;
 
        return 0;

diff --git a/lib/librte_vhost/vhost_user.c b/lib/librte_vhost/vhost_user.c
index e4ae027a0554aae9c3d31f6a7330ff275dc331ba..3d2db6edff55b1ef87a478c78800f80f0ebd7275 100644 (file)
--- a/lib/librte_vhost/vhost_user.c
+++ b/lib/librte_vhost/vhost_user.c
@@ -622,6 +622,7 @@ translate_ring_addresses(struct virtio_net *dev, int vq_index)
                        return dev;
                }
 
+               vq->access_ok = 1;
                return dev;
        }
 
@@ -680,6 +681,7 @@ translate_ring_addresses(struct virtio_net *dev, int vq_index)
        }
 
        vq->log_guest_addr = addr->log_guest_addr;
+       vq->access_ok = 1;
 
        VHOST_LOG_DEBUG(VHOST_CONFIG, "(%d) mapped address desc: %p\n",
                        dev->vid, vq->desc);
@@ -704,6 +706,7 @@ vhost_user_set_vring_addr(struct virtio_net **pdev, struct VhostUserMsg *msg,
        struct virtio_net *dev = *pdev;
        struct vhost_virtqueue *vq;
        struct vhost_vring_addr *addr = &msg->payload.addr;
+       bool access_ok;
 
        if (dev->mem == NULL)
                return RTE_VHOST_MSG_RESULT_ERR;
@@ -711,6 +714,8 @@ vhost_user_set_vring_addr(struct virtio_net **pdev, struct VhostUserMsg *msg,
        /* addr->index refers to the queue index. The txq 1, rxq is 0. */
        vq = dev->virtqueue[msg->payload.addr.index];
 
+       access_ok = vq->access_ok;
+
        /*
         * Rings addresses should not be interpreted as long as the ring is not
         * started and enabled
@@ -719,8 +724,9 @@ vhost_user_set_vring_addr(struct virtio_net **pdev, struct VhostUserMsg *msg,
 
        vring_invalidate(dev, vq);
 
-       if (vq->enabled && (dev->features &
-                               (1ULL << VHOST_USER_F_PROTOCOL_FEATURES))) {
+       if ((vq->enabled && (dev->features &
+                               (1ULL << VHOST_USER_F_PROTOCOL_FEATURES))) ||
+                       access_ok) {
                dev = translate_ring_addresses(dev, msg->payload.addr.index);
                if (!dev)
                        return RTE_VHOST_MSG_RESULT_ERR;
@@ -1325,6 +1331,8 @@ vhost_user_get_vring_base(struct virtio_net **pdev,
        msg->size = sizeof(msg->payload.state);
        msg->fd_num = 0;
 
+       vring_invalidate(dev, vq);
+
        return RTE_VHOST_MSG_RESULT_REPLY;
 }