Re: [PATCH] xen: netfront: Drop GSO SKBs which do not have csum_blank.
flat view
From: Ian Campbell <hidden>
Date: 2011-01-22 09:43:21
Also in:
xen-devel
On Sat, 2011-01-22 at 00:58 +0000, Jeremy Fitzhardinge wrote:
quoted hunk ↗ jump to hunk
On 01/05/2011 05:23 AM, Ian Campbell wrote:quoted
The Linux network stack expects all GSO SKBs to have ip_summed == CHECKSUM_PARTIAL (which implies that the frame contains a partial checksum) and the Xen network ring protocol similarly expects an SKB which has GSO set to also have NETRX_csum_blank (which also implies a partial checksum). Therefore drop such frames on receive otherwise they will trigger the warning in skb_gso_segment. Signed-off-by: Ian Campbell <redacted> Cc: Jeremy Fitzhardinge <redacted> Cc: xen-devel@lists.xensource.com Cc: netdev@vger.kernel.org --- drivers/net/xen-netfront.c | 5 +++++ 1 files changed, 5 insertions(+), 0 deletions(-)diff --git a/drivers/net/xen-netfront.c b/drivers/net/xen-netfront.c index cdbeec9..8b8c480 100644 --- a/drivers/net/xen-netfront.c +++ b/drivers/net/xen-netfront.c@@ -836,6 +836,11 @@ static int handle_incoming_queue(struct net_device *dev, dev->stats.rx_errors++; continue; } + } else if (skb_is_gso(skb)) { + kfree_skb(skb); + packets_dropped++; + dev->stats.rx_errors++; + continue;This looks redundant; why not something like:diff --git a/drivers/net/xen-netfront.c b/drivers/net/xen-netfront.c index 47e6a71..c1b8f64 100644 --- a/drivers/net/xen-netfront.c +++ b/drivers/net/xen-netfront.c@@ -852,13 +852,12 @@ static int handle_incoming_queue(struct net_device *dev, /* Ethernet work: Delayed to here as it peeks the header. */ skb->protocol = eth_type_trans(skb, dev); - if (skb->ip_summed == CHECKSUM_PARTIAL) { - if (skb_checksum_setup(skb)) { - kfree_skb(skb); - packets_dropped++; - dev->stats.rx_errors++; - continue; - } + if (skb->ip_summed != CHECKSUM_PARTIAL || + skb_checksum_setup(skb)) {
That drops non-partial skbs. However they are fine unless they also claim to be gso. Perhaps you meant "skb->ip_summed == CHECKSUM_PARTIAL && ! skb_checksum_setup(skb)" which I think works but doesn't allow us to correctly chain the gso check onto the else. Ian.
+ kfree_skb(skb); + packets_dropped++; + dev->stats.rx_errors++; + continue; } dev->stats.rx_packets++; Thanks, J