net: Support RXFCS feature flag.
When set on hardware that supports the feature,
this causes the Ethernet FCS to be appended
to the end of the skb.
Useful for sniffing packets.
Signed-off-by: Ben Greear <greearb@candelatech.com>
Tested-by: Aaron Brown <aaron.f.brown@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
diff --git a/Documentation/networking/netdev-features.txt b/Documentation/networking/netdev-features.txt
index 4b1c0dc..7d27812 100644
--- a/Documentation/networking/netdev-features.txt
+++ b/Documentation/networking/netdev-features.txt
@@ -152,3 +152,9 @@
headers. Some drivers set this because the cards can't handle the bigger MTU.
[FIXME: Those cases could be fixed in VLAN code by allowing only reduced-MTU
VLANs. This may be not useful, though.]
+
+* rx-fcs
+
+This requests that the NIC append the Ethernet Frame Checksum (FCS)
+to the end of the skb data. This allows sniffers and other tools to
+read the CRC recorded by the NIC on receipt of the packet.