summaryrefslogtreecommitdiff
diff options
context:
space:
mode:
authorVladimir Oltean <vladimir.oltean@nxp.com>2022-02-16 17:30:14 +0300
committerDavid S. Miller <davem@davemloft.net>2022-02-17 17:06:51 +0300
commit29940ce32a2da2f3857d5fc459c6df6e47adb67e (patch)
tree3820a0b33aeba63c2c6527abc01e33d042d1ca02
parent9934800436552d2a4af4aaca62d779b33d1f6a63 (diff)
downloadlinux-29940ce32a2da2f3857d5fc459c6df6e47adb67e.tar.xz
net: dsa: tag_ocelot_8021q: calculate TX checksum in software for deferred packets
DSA inherits NETIF_F_CSUM_MASK from master->vlan_features, and the expectation is that TX checksumming is offloaded and not done in software. Normally the DSA master takes care of this, but packets handled by ocelot_defer_xmit() are a very special exception, because they are actually injected into the switch through register-based MMIO. So the DSA master is not involved at all for these packets => no one calculates the checksum. This allows PTP over UDP to work using the ocelot-8021q tagging protocol. Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com> Signed-off-by: David S. Miller <davem@davemloft.net>
-rw-r--r--net/dsa/tag_ocelot_8021q.c7
1 files changed, 7 insertions, 0 deletions
diff --git a/net/dsa/tag_ocelot_8021q.c b/net/dsa/tag_ocelot_8021q.c
index 68982b2789a5..bd6f1d0e5372 100644
--- a/net/dsa/tag_ocelot_8021q.c
+++ b/net/dsa/tag_ocelot_8021q.c
@@ -32,6 +32,13 @@ static struct sk_buff *ocelot_defer_xmit(struct dsa_port *dp,
if (!xmit_work_fn || !xmit_worker)
return NULL;
+ /* PTP over IP packets need UDP checksumming. We may have inherited
+ * NETIF_F_HW_CSUM from the DSA master, but these packets are not sent
+ * through the DSA master, so calculate the checksum here.
+ */
+ if (skb->ip_summed == CHECKSUM_PARTIAL && skb_checksum_help(skb))
+ return NULL;
+
xmit_work = kzalloc(sizeof(*xmit_work), GFP_ATOMIC);
if (!xmit_work)
return NULL;