5.15-stable review patch. If anyone has any objections, please let me know.
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From: Kohei Enju enjuk@amazon.com
[ Upstream commit f017156aea60db8720e47591ed1e041993381ad2 ]
In EC2 instances where the RSS hash key is not configurable, ethtool shows bogus RSS hash key since ena_get_rxfh_key_size() unconditionally returns ENA_HASH_KEY_SIZE.
Commit 6a4f7dc82d1e ("net: ena: rss: do not allocate key when not supported") added proper handling for devices that don't support RSS hash key configuration, but ena_get_rxfh_key_size() has been unchanged.
When the RSS hash key is not configurable, return 0 instead of ENA_HASH_KEY_SIZE to clarify getting the value is not supported.
Tested on m5 instance families.
Without patch: # ethtool -x ens5 | grep -A 1 "RSS hash key" RSS hash key: 00:00:00:00:00:00:00:00:00:00:00:00:00:00:00:00:00:00:00:00:00:00:00:00:00:00:00:00:00:00:00:00:00:00:00:00:00:00:00:00
With patch: # ethtool -x ens5 | grep -A 1 "RSS hash key" RSS hash key: Operation not supported
Fixes: 6a4f7dc82d1e ("net: ena: rss: do not allocate key when not supported") Signed-off-by: Kohei Enju enjuk@amazon.com Link: https://patch.msgid.link/20250929050247.51680-1-enjuk@amazon.com Signed-off-by: Jakub Kicinski kuba@kernel.org Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/net/ethernet/amazon/ena/ena_ethtool.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-)
diff --git a/drivers/net/ethernet/amazon/ena/ena_ethtool.c b/drivers/net/ethernet/amazon/ena/ena_ethtool.c index 413082f10dc1c..31f05356a7c06 100644 --- a/drivers/net/ethernet/amazon/ena/ena_ethtool.c +++ b/drivers/net/ethernet/amazon/ena/ena_ethtool.c @@ -688,7 +688,10 @@ static u32 ena_get_rxfh_indir_size(struct net_device *netdev)
static u32 ena_get_rxfh_key_size(struct net_device *netdev) { - return ENA_HASH_KEY_SIZE; + struct ena_adapter *adapter = netdev_priv(netdev); + struct ena_rss *rss = &adapter->ena_dev->rss; + + return rss->hash_key ? ENA_HASH_KEY_SIZE : 0; }
static int ena_indirection_table_set(struct ena_adapter *adapter,