On Tue, Jun 08, 2021 at 03:34:36PM +0300, Andrew Rybchenko wrote:

On 6/8/21 3:29 PM, Olivier Matz wrote:

quoted

Hi Ferruh, Andrew,

On Tue, Jun 08, 2021 at 01:13:59PM +0300, Andrew Rybchenko wrote:

quoted

On 4/30/21 5:48 PM, Ferruh Yigit wrote:

quoted

On 4/27/2021 2:57 PM, Olivier Matz wrote:

quoted

When packet type is IPV4_EXT, the checksum is always marked as good in
the mbuf offload flags.

Since we know the header lengths, we can easily call
rte_ipv4_udptcp_cksum() in this case too.

Fixes: 8ae3023387e9 ("net/tap: add Rx/Tx checksum offload support")
Cc: stable@dpdk.org

Signed-off-by: Olivier Matz <redacted>
---
 drivers/net/tap/rte_eth_tap.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/net/tap/rte_eth_tap.c b/drivers/net/tap/rte_eth_tap.c
index 68baa18523..e7b185a4b5 100644
--- a/drivers/net/tap/rte_eth_tap.c
+++ b/drivers/net/tap/rte_eth_tap.c

@@ -350,7 +350,7 @@ tap_verify_csum(struct rte_mbuf *mbuf)
 		/* Don't verify checksum for multi-segment packets. */
 		if (mbuf->nb_segs > 1)
 			return;
-		if (l3 == RTE_PTYPE_L3_IPV4) {
+		if (l3 == RTE_PTYPE_L3_IPV4 || l3 == RTE_PTYPE_L3_IPV4_EXT) {

Should we take 'RTE_PTYPE_L3_IPV4_EXT_UNKNOWN' into account?

I think we should.

I think 'RTE_PTYPE_L3_IPV4_EXT_UNKNOWN' cannot happen here:

- mbuf->packet_type is generated by 

(), which cannot

quoted

  return 'RTE_PTYPE_L3_IPV4_EXT_UNKNOWN'

My question if it is guaranteed and the only possible branch.
Can application set packet_type itself and do not call
rte_net_get_ptype(). Yes, typically application knows
if it has IPv4 options in the header or not, but theoretically
could be unaware as well.

This function is called on the Rx path from pmd_rx_burst(), so
the application does not have access to the mbuf.

The software parser that sets the packet type returns either
RTE_PTYPE_L3_IPV4 if there is no option, or RTE_PTYPE_L3_IPV4_EXT
else. The value RTE_PTYPE_L3_IPV4_EXT_UNKNOWN is used by PMDs that don't
know if there are options.

quoted

- right above this code, we already returned if l3 is not in
  (RTE_PTYPE_L3_IPV4, RTE_PTYPE_L3_IPV4_EXT, RTE_PTYPE_L3_IPV6)

If so, it sounds like it should be allowed above as well.

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 			if (l4 == RTE_PTYPE_L4_UDP) {
 				udp_hdr = (struct rte_udp_hdr *)l4_hdr;
 				if (udp_hdr->dgram_cksum == 0) {

@@ -364,7 +364,7 @@ tap_verify_csum(struct rte_mbuf *mbuf)
 				}
 			}
 			cksum = ~rte_ipv4_udptcp_cksum(l3_hdr, l4_hdr);
-		} else if (l3 == RTE_PTYPE_L3_IPV6) {
+		} else { /* l3 == RTE_PTYPE_L3_IPV6, checked above */
 			cksum = ~rte_ipv6_udptcp_cksum(l3_hdr, l4_hdr);
 		}
 		mbuf->ol_flags |= cksum ?