From ee8a9600b5391f434905c46bec7f77d34505083e Mon Sep 17 00:00:00 2001 From: David Thompson Date: Wed, 15 Sep 2021 14:08:48 -0400 Subject: [PATCH] mlxbf_gige: clear valid_polarity upon open The network interface managed by the mlxbf_gige driver can get into a problem state where traffic does not flow. In this state, the interface will be up and enabled, but will stop processing received packets. This problem state will happen if three specific conditions occur: 1) driver has received more than (N * RxRingSize) packets but less than (N+1 * RxRingSize) packets, where N is an odd number Note: the command "ethtool -g " will display the current receive ring size, which currently defaults to 128 2) the driver's interface was disabled via "ifconfig oob_net0 down" during the window described in #1. 3) the driver's interface is re-enabled via "ifconfig oob_net0 up" This patch ensures that the driver's "valid_polarity" field is cleared during the open() method so that it always matches the receive polarity used by hardware. Without this fix, the driver needs to be unloaded and reloaded to correct this problem state. Fixes: f92e1869d74e ("Add Mellanox BlueField Gigabit Ethernet driver") Reviewed-by: Asmaa Mnebhi Signed-off-by: David Thompson Signed-off-by: David S. Miller --- drivers/net/ethernet/mellanox/mlxbf_gige/mlxbf_gige_main.c | 7 +++++++ 1 file changed, 7 insertions(+) diff --git a/drivers/net/ethernet/mellanox/mlxbf_gige/mlxbf_gige_main.c b/drivers/net/ethernet/mellanox/mlxbf_gige/mlxbf_gige_main.c index 3e85b17f58573..6704f5c1aa32e 100644 --- a/drivers/net/ethernet/mellanox/mlxbf_gige/mlxbf_gige_main.c +++ b/drivers/net/ethernet/mellanox/mlxbf_gige/mlxbf_gige_main.c @@ -142,6 +142,13 @@ static int mlxbf_gige_open(struct net_device *netdev) err = mlxbf_gige_clean_port(priv); if (err) goto free_irqs; + + /* Clear driver's valid_polarity to match hardware, + * since the above call to clean_port() resets the + * receive polarity used by hardware. + */ + priv->valid_polarity = 0; + err = mlxbf_gige_rx_init(priv); if (err) goto free_irqs; -- 2.39.5