net/virtio: fix advertised Rx offload capabilities

When the virtio PMD is used on top of a vhost that does not support
offloads, Rx offload capabilities are still advertised by
virtio_dev_info_get(). But if an application tries to start the PMD with
Rx offloads enabled (rxmode.hw_ip_checksum = 1), the initialization of
the device will fail with -ENOTSUP and the following log:

  rx ip checksum not available on this host

This patch fixes the Rx offload capabilities returned by
virtio_dev_info_get() to be consistent with features advertised by the
host.

Fixes: 96cb6711939e ("net/virtio: support Rx checksum offload")
Fixes: 86d59b21468a ("net/virtio: support LRO")
Cc: stable@dpdk.org
Signed-off-by: Olivier Matz <olivier.matz@6wind.com>
Acked-by: Yuanhan Liu <yuanhan.liu@linux.intel.com>

diff --git a/drivers/net/virtio/virtio_ethdev.c b/drivers/net/virtio/virtio_ethdev.c
index d580257..0fe99d5 100644 (file)
--- a/drivers/net/virtio/virtio_ethdev.c
+++ b/drivers/net/virtio/virtio_ethdev.c
@@ -1829,7 +1829,7 @@ virtio_dev_link_update(struct rte_eth_dev *dev, __rte_unused int wait_to_complet
 static void
 virtio_dev_info_get(struct rte_eth_dev *dev, struct rte_eth_dev_info *dev_info)
 {
-       uint64_t tso_mask;
+       uint64_t tso_mask, host_features;
        struct virtio_hw *hw = dev->data->dev_private;
 
        dev_info->pci_dev = dev->device ? RTE_DEV_TO_PCI(dev->device) : NULL;
@@ -1843,18 +1843,25 @@ virtio_dev_info_get(struct rte_eth_dev *dev, struct rte_eth_dev_info *dev_info)
        dev_info->default_txconf = (struct rte_eth_txconf) {
                .txq_flags = ETH_TXQ_FLAGS_NOOFFLOADS
        };
-       dev_info->rx_offload_capa =
-               DEV_RX_OFFLOAD_TCP_CKSUM |
-               DEV_RX_OFFLOAD_UDP_CKSUM |
-               DEV_RX_OFFLOAD_TCP_LRO;
-       dev_info->tx_offload_capa = 0;
 
+       host_features = VTPCI_OPS(hw)->get_features(hw);
+       dev_info->rx_offload_capa = 0;
+       if (host_features & (1ULL << VIRTIO_NET_F_GUEST_CSUM)) {
+               dev_info->rx_offload_capa |=
+                       DEV_RX_OFFLOAD_TCP_CKSUM |
+                       DEV_RX_OFFLOAD_UDP_CKSUM;
+       }
+       tso_mask = (1ULL << VIRTIO_NET_F_GUEST_TSO4) |
+               (1ULL << VIRTIO_NET_F_GUEST_TSO6);
+       if ((host_features & tso_mask) == tso_mask)
+               dev_info->rx_offload_capa |= DEV_RX_OFFLOAD_TCP_LRO;
+
+       dev_info->tx_offload_capa = 0;
        if (hw->guest_features & (1ULL << VIRTIO_NET_F_CSUM)) {
                dev_info->tx_offload_capa |=
                        DEV_TX_OFFLOAD_UDP_CKSUM |
                        DEV_TX_OFFLOAD_TCP_CKSUM;
        }
-
        tso_mask = (1ULL << VIRTIO_NET_F_HOST_TSO4) |
                (1ULL << VIRTIO_NET_F_HOST_TSO6);
        if ((hw->guest_features & tso_mask) == tso_mask)