[PATCH net-next v2 0/2] mlx4: avoid devlink port type not set warnings

[PATCH net-next v2 0/2] mlx4: avoid devlink port type not set warnings

[Jakub Kicinski]

Hi!

This small set addresses the issue of mlx4 potentially not setting
devlink port type when Ethernet or IB driver is not built, but
port has that type.

v2:
 - add patch 1

Jakub Kicinski (2):
  devlink: don't crash if netdev is NULL
  mlx4: make sure to always set the port type

 drivers/net/ethernet/mellanox/mlx4/main.c | 11 +++++++++
 net/core/devlink.c                        | 28 ++++++++++++++++-------
 2 files changed, 31 insertions(+), 8 deletions(-)

-- 
2.26.2

[PATCH net-next v2 1/2] devlink: don't crash if netdev is NULL

[Jakub Kicinski]

Following change will add support for a corner case where
we may not have a netdev to pass to devlink_port_type_eth_set()
but we still want to set port type.

This is definitely a corner case, and drivers should not normally
pass NULL netdev - print a warning message when this happens.

Sadly for other port types (ib) switches don't have a device
reference, the way we always do for Ethernet, so we can't put
the warning in __devlink_port_type_set().

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
---
 net/core/devlink.c | 28 ++++++++++++++++++++--------
 1 file changed, 20 insertions(+), 8 deletions(-)

diff --git a/net/core/devlink.c b/net/core/devlink.c
index 49e911c19881..31cac8365b22 100644
--- a/net/core/devlink.c
+++ b/net/core/devlink.c
@@ -7603,14 +7603,8 @@ static void __devlink_port_type_set(struct devlink_port *devlink_port,
 	devlink_port_notify(devlink_port, DEVLINK_CMD_PORT_NEW);
 }
 
-/**
- *	devlink_port_type_eth_set - Set port type to Ethernet
- *
- *	@devlink_port: devlink port
- *	@netdev: related netdevice
- */
-void devlink_port_type_eth_set(struct devlink_port *devlink_port,
-			       struct net_device *netdev)
+static void devlink_port_type_netdev_checks(struct devlink_port *devlink_port,
+					    struct net_device *netdev)
 {
 	const struct net_device_ops *ops = netdev->netdev_ops;
 
@@ -7644,6 +7638,24 @@ void devlink_port_type_eth_set(struct devlink_port *devlink_port,
 		err = ops->ndo_get_port_parent_id(netdev, &ppid);
 		WARN_ON(err != -EOPNOTSUPP);
 	}
+}
+
+/**
+ *	devlink_port_type_eth_set - Set port type to Ethernet
+ *
+ *	@devlink_port: devlink port
+ *	@netdev: related netdevice
+ */
+void devlink_port_type_eth_set(struct devlink_port *devlink_port,
+			       struct net_device *netdev)
+{
+	if (netdev)
+		devlink_port_type_netdev_checks(devlink_port, netdev);
+	else
+		dev_warn(devlink_port->devlink->dev,
+			 "devlink port type for port %d set to Ethernet without a software interface reference, device type not supported by the kernel?\n",
+			 devlink_port->index);
+
 	__devlink_port_type_set(devlink_port, DEVLINK_PORT_TYPE_ETH, netdev);
 }
 EXPORT_SYMBOL_GPL(devlink_port_type_eth_set);
-- 
2.26.2

[PATCH net-next v2 2/2] mlx4: make sure to always set the port type

[Jakub Kicinski]

Even tho mlx4_core registers the devlink ports, it's mlx4_en
and mlx4_ib which set their type. In situations where one of
the two is not built yet the machine has ports of given type
we see the devlink warning from devlink_port_type_warn() trigger.

Having ports of a type not supported by the kernel may seem
surprising, but it does occur in practice - when the unsupported
port is not plugged in to a switch anyway users are more than happy
not to see it (and potentially allocate any resources to it).

Set the type in mlx4_core if type-specific driver is not built.

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
---
 drivers/net/ethernet/mellanox/mlx4/main.c | 11 +++++++++++
 1 file changed, 11 insertions(+)

diff --git a/drivers/net/ethernet/mellanox/mlx4/main.c b/drivers/net/ethernet/mellanox/mlx4/main.c
index 258c7a96f269..70cf24ba71e4 100644
--- a/drivers/net/ethernet/mellanox/mlx4/main.c
+++ b/drivers/net/ethernet/mellanox/mlx4/main.c
@@ -3031,6 +3031,17 @@ static int mlx4_init_port_info(struct mlx4_dev *dev, int port)
 	if (err)
 		return err;
 
+	/* Ethernet and IB drivers will normally set the port type,
+	 * but if they are not built set the type now to prevent
+	 * devlink_port_type_warn() from firing.
+	 */
+	if (!IS_ENABLED(CONFIG_MLX4_EN) &&
+	    dev->caps.port_type[port] == MLX4_PORT_TYPE_ETH)
+		devlink_port_type_eth_set(&info->devlink_port, NULL);
+	else if (!IS_ENABLED(CONFIG_MLX4_INFINIBAND) &&
+		 dev->caps.port_type[port] == MLX4_PORT_TYPE_IB)
+		devlink_port_type_ib_set(&info->devlink_port, NULL);
+
 	info->dev = dev;
 	info->port = port;
 	if (!mlx4_is_slave(dev)) {
-- 
2.26.2

Re: [PATCH net-next v2 2/2] mlx4: make sure to always set the port type

[Tariq Toukan]

On 9/9/2020 1:21 AM, Jakub Kicinski wrote:
> Even tho mlx4_core registers the devlink ports, it's mlx4_en
> and mlx4_ib which set their type. In situations where one of
> the two is not built yet the machine has ports of given type
> we see the devlink warning from devlink_port_type_warn() trigger.
> 
> Having ports of a type not supported by the kernel may seem
> surprising, but it does occur in practice - when the unsupported
> port is not plugged in to a switch anyway users are more than happy
> not to see it (and potentially allocate any resources to it).
> 
> Set the type in mlx4_core if type-specific driver is not built.
> 
> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
> ---
>   drivers/net/ethernet/mellanox/mlx4/main.c | 11 +++++++++++
>   1 file changed, 11 insertions(+)
> 
> diff --git a/drivers/net/ethernet/mellanox/mlx4/main.c b/drivers/net/ethernet/mellanox/mlx4/main.c
> index 258c7a96f269..70cf24ba71e4 100644
> --- a/drivers/net/ethernet/mellanox/mlx4/main.c
> +++ b/drivers/net/ethernet/mellanox/mlx4/main.c
> @@ -3031,6 +3031,17 @@ static int mlx4_init_port_info(struct mlx4_dev *dev, int port)
>   	if (err)
>   		return err;
>   
> +	/* Ethernet and IB drivers will normally set the port type,
> +	 * but if they are not built set the type now to prevent
> +	 * devlink_port_type_warn() from firing.
> +	 */
> +	if (!IS_ENABLED(CONFIG_MLX4_EN) &&
> +	    dev->caps.port_type[port] == MLX4_PORT_TYPE_ETH)
> +		devlink_port_type_eth_set(&info->devlink_port, NULL);
> +	else if (!IS_ENABLED(CONFIG_MLX4_INFINIBAND) &&
> +		 dev->caps.port_type[port] == MLX4_PORT_TYPE_IB)
> +		devlink_port_type_ib_set(&info->devlink_port, NULL);
> +
>   	info->dev = dev;
>   	info->port = port;
>   	if (!mlx4_is_slave(dev)) {
> 

Reviewed-by: Tariq Toukan <tariqt@mellanox.com>

Re: [PATCH net-next v2 0/2] mlx4: avoid devlink port type not set warnings

[David Miller]

From: Jakub Kicinski <kuba@kernel.org>
Date: Tue,  8 Sep 2020 15:21:12 -0700

> This small set addresses the issue of mlx4 potentially not setting
> devlink port type when Ethernet or IB driver is not built, but
> port has that type.
> 
> v2:
>  - add patch 1

Series applied, thank you.