[bionic:linux-azure-4.15][PATCH 2/2] hv_netvsc: make recording RSS hash depend on feature flag

[Marcelo Henrique Cerri]

From: Dexuan Cui <decui at microsoft.com>

BugLink: https://bugs.launchpad.net/bugs/1902531

The recording of RSS hash should be controlled by NETIF_F_RXHASH.

Fixes: 1fac7ca4e63b ("hv_netvsc: record hardware hash in skb")
Suggested-by: Eric Dumazet <eric.dumazet at gmail.com>
Signed-off-by: Stephen Hemminger <sthemmin at microsoft.com>
Signed-off-by: Haiyang Zhang <haiyangz at microsoft.com>
Reviewed-by: Michael Kelley <mikelley at microsoft.com>
Signed-off-by: Jakub Kicinski <jakub.kicinski at netronome.com>

This is a backport of the below commit in the mainline kernel:
commit 6f3aeb1ba05d ("hv_netvsc: make recording RSS hash depend on feature flag")

Cc: Haiyang Zhang <haiyangz at microsoft.com>
Signed-off-by: Dexuan Cui <decui at microsoft.com>
Signed-off-by: Marcelo Henrique Cerri <marcelo.cerri at canonical.com>
---
 drivers/net/hyperv/hyperv_net.h   | 2 +-
 drivers/net/hyperv/netvsc_drv.c   | 2 +-
 drivers/net/hyperv/rndis_filter.c | 1 +
 3 files changed, 3 insertions(+), 2 deletions(-)

diff --git a/drivers/net/hyperv/hyperv_net.h b/drivers/net/hyperv/hyperv_net.h
index 58ba775d8dd2..a18f1a4ad33d 100644
--- a/drivers/net/hyperv/hyperv_net.h
+++ b/drivers/net/hyperv/hyperv_net.h
@@ -827,7 +827,7 @@ struct nvsp_message {
 
 #define NETVSC_SUPPORTED_HW_FEATURES (NETIF_F_RXCSUM | NETIF_F_IP_CSUM | \
 				      NETIF_F_TSO | NETIF_F_IPV6_CSUM | \
-				      NETIF_F_TSO6)
+				      NETIF_F_TSO6 | NETIF_F_RXHASH)
 
 #define VRSS_SEND_TAB_SIZE 16  /* must be power of 2 */
 #define VRSS_CHANNEL_MAX 64
diff --git a/drivers/net/hyperv/netvsc_drv.c b/drivers/net/hyperv/netvsc_drv.c
index 391d67feedaa..d8bade2c13ce 100644
--- a/drivers/net/hyperv/netvsc_drv.c
+++ b/drivers/net/hyperv/netvsc_drv.c
@@ -817,7 +817,7 @@ static struct sk_buff *netvsc_alloc_recv_skb(struct net_device *net,
 			skb->ip_summed = CHECKSUM_UNNECESSARY;
 	}
 
-	if (hash_info)
+	if (hash_info && (net->features & NETIF_F_RXHASH))
 		skb_set_hash(skb, *hash_info, PKT_HASH_TYPE_L4);
 
 	if (vlan) {
diff --git a/drivers/net/hyperv/rndis_filter.c b/drivers/net/hyperv/rndis_filter.c
index 02b784efa1c8..df85b75b75a3 100644
--- a/drivers/net/hyperv/rndis_filter.c
+++ b/drivers/net/hyperv/rndis_filter.c
@@ -1145,6 +1145,7 @@ static int rndis_netdev_set_hwcaps(struct rndis_device *rndis_device,
 
 	/* Compute tx offload settings based on hw capabilities */
 	net->hw_features |= NETIF_F_RXCSUM;
+	net->hw_features |= NETIF_F_RXHASH;
 
 	if ((hwcaps.csum.ip4_txcsum & NDIS_TXCSUM_ALL_TCP4) == NDIS_TXCSUM_ALL_TCP4) {
 		/* Can checksum TCP */
-- 
2.25.1