Hi Olivier,

Thanks for the review.
Please find the comments inline below:

On Wed, Jun 30, 2021 at 3:09 PM Olivier Matz [off-list ref] wrote:

Hi Mohsin,

Hope you are fine!
Please see my comments below.

On Wed, Jun 30, 2021 at 01:04:04PM +0200, Mohsin Kazmi wrote:

quoted

Re: [PATCH v2] net: prepare the outer ipv4 hdr for checksum

I suggest to highlight that it this is the Intel-specific tx-prepare
function in the commit title. What about:

  net: fix Intel-specific Tx preparation for outer checksums

I'll update the commit title as suggested.

Preparation the headers for the hardware offload

quoted

misses the outer ipv4 checksum offload.
It results in bad checksum computed by hardware NIC.

This patch fixes the issue by setting the outer ipv4
checksum field to 0.

Fixes: 4fb7e803eb1a ("ethdev: add Tx preparation")
Cc: stable@dpdk.org

Signed-off-by: Mohsin Kazmi <redacted>
Acked-by: Qi Zhang <redacted>
---

v2:
* Update the commit message with Fixes.
---
 lib/net/rte_net.h | 12 +++++++++++-
 1 file changed, 11 insertions(+), 1 deletion(-)

diff --git a/lib/net/rte_net.h b/lib/net/rte_net.h
index 434435ffa2..e47365099e 100644
--- a/lib/net/rte_net.h
+++ b/lib/net/rte_net.h

@@ -128,8 +128,18 @@ rte_net_intel_cksum_flags_prepare(struct rte_mbuf

*m, uint64_t ol_flags)

quoted

      if (!(ol_flags & (PKT_TX_IP_CKSUM | PKT_TX_L4_MASK |

PKT_TX_TCP_SEG)))

quoted

              return 0;

I think this test should be updated too with PKT_TX_OUTER_IP_CKSUM.

Thanks. Yes, I'll update it too.

quoted

-     if (ol_flags & (PKT_TX_OUTER_IPV4 | PKT_TX_OUTER_IPV6))
+     if (ol_flags & (PKT_TX_OUTER_IPV4 | PKT_TX_OUTER_IPV6)) {
              inner_l3_offset += m->outer_l2_len + m->outer_l3_len;
+             /*
+              * prepare outer ipv4 header checksum by setting it to 0,
+              * in order to be computed by hardware NICs.
+              */
+             if (ol_flags & PKT_TX_OUTER_IP_CKSUM) {
+                     ipv4_hdr = rte_pktmbuf_mtod_offset(m,
+                                     struct rte_ipv4_hdr *,

m->outer_l2_len);

quoted

+                     ipv4_hdr->hdr_checksum = 0;
+             }
+     }

What about outer L4 checksum? Does it requires the same than inner?

I am using XL710 for my testing with i40e dpdk driver. AFAIK, It doesn't
support outer l4 checksum. I am not sure if other Intel NICs support it.

quoted

      /*
       * Check if headers are fragmented.
--
2.17.1