[PATCH AUTOSEL 4.19 17/25] net: ena: rss: fix failure to get indirection table

From: Sasha Levin
Date: Sat Feb 22 2020 - 21:29:41 EST


From: Sameeh Jubran <sameehj@xxxxxxxxxx>

[ Upstream commit 0c8923c0a64fb5d14bebb9a9065d2dc25ac5e600 ]

On old hardware, getting / setting the hash function is not supported while
gettting / setting the indirection table is.

This commit enables us to still show the indirection table on older
hardwares by setting the hash function and key to NULL.

Fixes: 1738cd3ed342 ("net: ena: Add a driver for Amazon Elastic Network Adapters (ENA)")
Signed-off-by: Sameeh Jubran <sameehj@xxxxxxxxxx>
Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
drivers/net/ethernet/amazon/ena/ena_ethtool.c | 14 ++++++++++++++
1 file changed, 14 insertions(+)

diff --git a/drivers/net/ethernet/amazon/ena/ena_ethtool.c b/drivers/net/ethernet/amazon/ena/ena_ethtool.c
index 237fbcac734f5..dc63aa912aebb 100644
--- a/drivers/net/ethernet/amazon/ena/ena_ethtool.c
+++ b/drivers/net/ethernet/amazon/ena/ena_ethtool.c
@@ -661,7 +661,21 @@ static int ena_get_rxfh(struct net_device *netdev, u32 *indir, u8 *key,
if (rc)
return rc;

+ /* We call this function in order to check if the device
+ * supports getting/setting the hash function.
+ */
rc = ena_com_get_hash_function(adapter->ena_dev, &ena_func, key);
+
+ if (rc) {
+ if (rc == -EOPNOTSUPP) {
+ key = NULL;
+ hfunc = NULL;
+ rc = 0;
+ }
+
+ return rc;
+ }
+
if (rc)
return rc;

--
2.20.1