net/netvsc: fix crash during Tx

Commit cc0251813277 ("net/netvsc: split send buffers from Tx
descriptors") changed the way that transmit descriptors are
allocated. They come from a single pool instead of being
individually attached to each mbuf. To find the IOVA, you need
to calculate the offset from the base of the pool.

Fixes: cc0251813277 ("net/netvsc: split send buffers from Tx descriptors")
Cc: stable@dpdk.org
Signed-off-by: Chas Williams <3chas3@gmail.com>
Acked-by: Stephen Hemminger <stephen@networkplumber.org>

diff --git a/drivers/net/netvsc/hn_rxtx.c b/drivers/net/netvsc/hn_rxtx.c
index 86a4c0d..0428c58 100644 (file)
--- a/drivers/net/netvsc/hn_rxtx.c
+++ b/drivers/net/netvsc/hn_rxtx.c
@@ -1421,11 +1421,12 @@ static int hn_xmit_sg(struct hn_tx_queue *txq,
        hn_rndis_dump(txd->rndis_pkt);
 
        /* pass IOVA of rndis header in first segment */
-       addr = rte_malloc_virt2iova(txd->rndis_pkt);
+       addr = rte_malloc_virt2iova(txq->tx_rndis);
        if (unlikely(addr == RTE_BAD_IOVA)) {
                PMD_DRV_LOG(ERR, "RNDIS transmit can not get iova");
                return -EINVAL;
        }
+       addr = addr + ((char *)txd->rndis_pkt - (char *)txq->tx_rndis);
 
        sg[0].page = addr / PAGE_SIZE;
        sg[0].ofs = addr & PAGE_MASK;