[dpdk-stable] [PATCH BUG 335 3/3] net/virtio: fix compilation error with 0 headroom

[Hemant Agrawal]

When using RTE_PKTMBUF_HEADROOM as 0, virito ethdev driver throws
compilation error
virtio_ethdev.c:1851:2: note: in expansion of macro ‘RTE_BUILD_BUG_ON’
RTE_BUILD_BUG_ON(RTE_PKTMBUF_HEADROOM
	< sizeof(struct virtio_net_hdr_mrg_rxbuf));

This patch change it into run-time check.
Reported as: https://bugs.dpdk.org/show_bug.cgi?id=335

Fixes: 198ab33677c9 ("net/virtio: move device initialization in a function")
Cc: stable at dpdk.org
Cc: Olivier Matz <olivier.matz at 6wind.com>

Signed-off-by: Hemant Agrawal <hemant.agrawal at nxp.com>
---
 drivers/net/virtio/virtio_ethdev.c | 9 ++++++++-
 1 file changed, 8 insertions(+), 1 deletion(-)

diff --git a/drivers/net/virtio/virtio_ethdev.c b/drivers/net/virtio/virtio_ethdev.c
index 62c827443..3e2e8bd2a 100644
--- a/drivers/net/virtio/virtio_ethdev.c
+++ b/drivers/net/virtio/virtio_ethdev.c
@@ -1848,7 +1848,14 @@ eth_virtio_dev_init(struct rte_eth_dev *eth_dev)
 	struct virtio_hw *hw = eth_dev->data->dev_private;
 	int ret;
 
-	RTE_BUILD_BUG_ON(RTE_PKTMBUF_HEADROOM < sizeof(struct virtio_net_hdr_mrg_rxbuf));
+	if (sizeof(struct virtio_net_hdr_mrg_rxbuf) > RTE_PKTMBUF_HEADROOM) {
+		PMD_INIT_LOG(ERR,
+			"Not sufficient headroom required = %d, avail = %d",
+			(int)sizeof(struct virtio_net_hdr_mrg_rxbuf),
+			RTE_PKTMBUF_HEADROOM);
+
+		return -1;
+	}
 
 	eth_dev->dev_ops = &virtio_eth_dev_ops;
 
-- 
2.17.1