netdev - [PATCH net 1/9] virtio-net: remove the warning before XDP linearizing

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Date:   Fri, 23 Dec 2016 22:37:24 +0800
From:   Jason Wang <jasowang@...hat.com>
To:     mst@...hat.com, virtualization@...ts.linux-foundation.org,
        netdev@...r.kernel.org, linux-kernel@...r.kernel.org
Cc:     john.r.fastabend@...el.com, Jason Wang <jasowang@...hat.com>
Subject: [PATCH net 1/9] virtio-net: remove the warning before XDP linearizing

Since we use EWMA to estimate the size of rx buffer. When rx buffer
size is underestimated, it's usual to have a packet with more than one
buffers. Consider this is not a bug, remove the warning and correct
the comment before XDP linearizing.

Cc: John Fastabend <john.r.fastabend@...el.com>
Signed-off-by: Jason Wang <jasowang@...hat.com>
---
 drivers/net/virtio_net.c | 8 +-------
 1 file changed, 1 insertion(+), 7 deletions(-)

diff --git a/drivers/net/virtio_net.c b/drivers/net/virtio_net.c
index 08327e0..1067253 100644
--- a/drivers/net/virtio_net.c
+++ b/drivers/net/virtio_net.c
@@ -552,14 +552,8 @@ static struct sk_buff *receive_mergeable(struct net_device *dev,
 		struct page *xdp_page;
 		u32 act;
 
-		/* No known backend devices should send packets with
-		 * more than a single buffer when XDP conditions are
-		 * met. However it is not strictly illegal so the case
-		 * is handled as an exception and a warning is thrown.
-		 */
+		/* This happens when rx buffer size is underestimated */
 		if (unlikely(num_buf > 1)) {
-			bpf_warn_invalid_xdp_buffer();
-
 			/* linearize data for XDP */
 			xdp_page = xdp_linearize_page(rq, num_buf,
 						      page, offset, &len);
-- 
2.7.4