[ PATCH v2 0/2] ibmveth gso fix.

[ PATCH v2 0/2] ibmveth gso fix.

[David Wilder]

The ibmveth driver is a virtual Ethernet driver used on IBM pSeries systems.
Gso packets can be sent between LPARS (virtual hosts) without segmentation,
by flagging gso packets using one of two methods depending on the firmware
version. Some gso packet were not correctly identified by the receiver.
This patch-set corrects this issue.

V2:
- Added fix tags.
- Byteswap the constant at compilation time.
- Updated the commit message to clarify what frame validation is performed
  by the hypervisor.

Signed-off-by: David Wilder <dwilder@us.ibm.com>
Reviewed-by: Thomas Falcon <tlfalcon@linux.ibm.com>
Reviewed-by: Cristobal Forno <cris.forno@ibm.com>
Reviewed-by: Pradeep Satyanarayana <pradeeps@linux.vnet.ibm.com>

David Wilder (2):
  ibmveth: Switch order of ibmveth_helper calls.
  ibmveth: Identify ingress large send packets.

 drivers/net/ethernet/ibm/ibmveth.c | 19 +++++++++++++++----
 1 file changed, 15 insertions(+), 4 deletions(-)

-- 
1.8.3.1

[ PATCH v2 1/2] ibmveth: Switch order of ibmveth_helper calls.

[David Wilder]

ibmveth_rx_csum_helper() must be called after ibmveth_rx_mss_helper()
as ibmveth_rx_csum_helper() may alter ip and tcp checksum values.

Fixes: 66aa0678efc2 ("ibmveth: Support to enable LSO/CSO for Trunk
VEA.")
Signed-off-by: David Wilder <dwilder@us.ibm.com>
Reviewed-by: Thomas Falcon <tlfalcon@linux.ibm.com>
Reviewed-by: Cristobal Forno <cris.forno@ibm.com>
Reviewed-by: Pradeep Satyanarayana <pradeeps@linux.vnet.ibm.com>
---
 drivers/net/ethernet/ibm/ibmveth.c | 10 +++++-----
 1 file changed, 5 insertions(+), 5 deletions(-)

diff --git a/drivers/net/ethernet/ibm/ibmveth.c b/drivers/net/ethernet/ibm/ibmveth.c
index c5c732601e35..3935a7e22ce5 100644
--- a/drivers/net/ethernet/ibm/ibmveth.c
+++ b/drivers/net/ethernet/ibm/ibmveth.c
@@ -1385,16 +1385,16 @@ static int ibmveth_poll(struct napi_struct *napi, int budget)
 			skb_put(skb, length);
 			skb->protocol = eth_type_trans(skb, netdev);
 
-			if (csum_good) {
-				skb->ip_summed = CHECKSUM_UNNECESSARY;
-				ibmveth_rx_csum_helper(skb, adapter);
-			}
-
 			if (length > netdev->mtu + ETH_HLEN) {
 				ibmveth_rx_mss_helper(skb, mss, lrg_pkt);
 				adapter->rx_large_packets++;
 			}
 
+			if (csum_good) {
+				skb->ip_summed = CHECKSUM_UNNECESSARY;
+				ibmveth_rx_csum_helper(skb, adapter);
+			}
+
 			napi_gro_receive(napi, skb);	/* send it up */
 
 			netdev->stats.rx_packets++;
-- 
1.8.3.1

Re: [ PATCH v2 1/2] ibmveth: Switch order of ibmveth_helper calls.

[Willem de Bruijn]

On Tue, Oct 13, 2020 at 7:21 PM David Wilder <dwilder@us.ibm.com> wrote:
>
> ibmveth_rx_csum_helper() must be called after ibmveth_rx_mss_helper()
> as ibmveth_rx_csum_helper() may alter ip and tcp checksum values.
>
> Fixes: 66aa0678efc2 ("ibmveth: Support to enable LSO/CSO for Trunk
> VEA.")
> Signed-off-by: David Wilder <dwilder@us.ibm.com>
> Reviewed-by: Thomas Falcon <tlfalcon@linux.ibm.com>
> Reviewed-by: Cristobal Forno <cris.forno@ibm.com>
> Reviewed-by: Pradeep Satyanarayana <pradeeps@linux.vnet.ibm.com>

Acked-by: Willem de Bruijn <willemb@google.com>

Re: [ PATCH v2 1/2] ibmveth: Switch order of ibmveth_helper calls.

[Jakub Kicinski]

On Tue, 13 Oct 2020 16:20:13 -0700 David Wilder wrote:
> Fixes: 66aa0678efc2 ("ibmveth: Support to enable LSO/CSO for Trunk
> VEA.")

Please make sure Fixes tags are not wrapped in the future.

[ PATCH v2 2/2] ibmveth: Identify ingress large send packets.

[David Wilder]

Ingress large send packets are identified by either:
The IBMVETH_RXQ_LRG_PKT flag in the receive buffer
or with a -1 placed in the ip header checksum.
The method used depends on firmware version. Frame
geometry and sufficient header validation is performed by the
hypervisor eliminating the need for further header checks here.

Fixes: 7b5967389f5a ("ibmveth: set correct gso_size and gso_type")
Signed-off-by: David Wilder <dwilder@us.ibm.com>
Reviewed-by: Thomas Falcon <tlfalcon@linux.ibm.com>
Reviewed-by: Cristobal Forno <cris.forno@ibm.com>
Reviewed-by: Pradeep Satyanarayana <pradeeps@linux.vnet.ibm.com>
---
 drivers/net/ethernet/ibm/ibmveth.c | 13 ++++++++++++-
 1 file changed, 12 insertions(+), 1 deletion(-)

diff --git a/drivers/net/ethernet/ibm/ibmveth.c b/drivers/net/ethernet/ibm/ibmveth.c
index 3935a7e22ce5..7ef3369953b6 100644
--- a/drivers/net/ethernet/ibm/ibmveth.c
+++ b/drivers/net/ethernet/ibm/ibmveth.c
@@ -1349,6 +1349,7 @@ static int ibmveth_poll(struct napi_struct *napi, int budget)
 			int offset = ibmveth_rxq_frame_offset(adapter);
 			int csum_good = ibmveth_rxq_csum_good(adapter);
 			int lrg_pkt = ibmveth_rxq_large_packet(adapter);
+			__sum16 iph_check = 0;
 
 			skb = ibmveth_rxq_get_buffer(adapter);
 
@@ -1385,7 +1386,17 @@ static int ibmveth_poll(struct napi_struct *napi, int budget)
 			skb_put(skb, length);
 			skb->protocol = eth_type_trans(skb, netdev);
 
-			if (length > netdev->mtu + ETH_HLEN) {
+			/* PHYP without PLSO support places a -1 in the ip
+			 * checksum for large send frames.
+			 */
+			if (skb->protocol == cpu_to_be16(ETH_P_IP)) {
+				struct iphdr *iph = (struct iphdr *)skb->data;
+
+				iph_check = iph->check;
+			}
+
+			if ((length > netdev->mtu + ETH_HLEN) ||
+			    lrg_pkt || iph_check == 0xffff) {
 				ibmveth_rx_mss_helper(skb, mss, lrg_pkt);
 				adapter->rx_large_packets++;
 			}
-- 
1.8.3.1

Re: [ PATCH v2 2/2] ibmveth: Identify ingress large send packets.

[Willem de Bruijn]

On Tue, Oct 13, 2020 at 7:21 PM David Wilder <dwilder@us.ibm.com> wrote:
>
> Ingress large send packets are identified by either:
> The IBMVETH_RXQ_LRG_PKT flag in the receive buffer
> or with a -1 placed in the ip header checksum.
> The method used depends on firmware version. Frame
> geometry and sufficient header validation is performed by the
> hypervisor eliminating the need for further header checks here.
>
> Fixes: 7b5967389f5a ("ibmveth: set correct gso_size and gso_type")
> Signed-off-by: David Wilder <dwilder@us.ibm.com>
> Reviewed-by: Thomas Falcon <tlfalcon@linux.ibm.com>
> Reviewed-by: Cristobal Forno <cris.forno@ibm.com>
> Reviewed-by: Pradeep Satyanarayana <pradeeps@linux.vnet.ibm.com>

Acked-by: Willem de Bruijn <willemb@google.com>

Thanks for clarifying the header validation. I clearly had missed that :)

Re: [ PATCH v2 0/2] ibmveth gso fix.

[Jakub Kicinski]

On Tue, 13 Oct 2020 16:20:12 -0700 David Wilder wrote:
> The ibmveth driver is a virtual Ethernet driver used on IBM pSeries systems.
> Gso packets can be sent between LPARS (virtual hosts) without segmentation,
> by flagging gso packets using one of two methods depending on the firmware
> version. Some gso packet were not correctly identified by the receiver.
> This patch-set corrects this issue.
> 
> V2:
> - Added fix tags.
> - Byteswap the constant at compilation time.
> - Updated the commit message to clarify what frame validation is performed
>   by the hypervisor.

Applied, thanks everyone!