Re: [PATCH] net: ethernet: ti: am65-cpsw: Fix devlink port register sequence

From: Jakub Kicinski
Date: Fri Jun 24 2022 - 19:42:48 EST


On Thu, 23 Jun 2022 10:13:37 +0530 Siddharth Vadapalli wrote:
> Renaming interfaces using udevd depends on the interface being registered
> before its netdev is registered. Otherwise, udevd reads an empty
> phys_port_name value, resulting in the interface not being renamed.
>
> Fix this by registering the interface before registering its netdev
> by invoking am65_cpsw_nuss_register_devlink() before invoking
> register_netdev() for the interface.
>
> Signed-off-by: Siddharth Vadapalli <s-vadapalli@xxxxxx>

Please add a Fixes tag and [PATCH net] in the subject.

> diff --git a/drivers/net/ethernet/ti/am65-cpsw-nuss.c b/drivers/net/ethernet/ti/am65-cpsw-nuss.c
> index fb92d4c1547d..47a6c4e5360b 100644
> --- a/drivers/net/ethernet/ti/am65-cpsw-nuss.c
> +++ b/drivers/net/ethernet/ti/am65-cpsw-nuss.c
> @@ -2527,6 +2527,10 @@ static int am65_cpsw_nuss_register_ndevs(struct am65_cpsw_common *common)
> return ret;
> }
>
> + ret = am65_cpsw_nuss_register_devlink(common);
> + if (ret)
> + goto err_cleanup_ndev;

You need to take the devlink_port_type_eth_set() out of this function
if it's now called before netdev registration and call it after netdev
registration. Otherwise devlink will generate a netlink notification
about the port state change with a half-initialized netdev.

> for (i = 0; i < common->port_num; i++) {
> port = &common->ports[i];
>
> @@ -2545,17 +2549,12 @@ static int am65_cpsw_nuss_register_ndevs(struct am65_cpsw_common *common)
> if (ret)
> goto err_cleanup_ndev;
>
> - ret = am65_cpsw_nuss_register_devlink(common);
> - if (ret)
> - goto clean_unregister_notifiers;
> -
> /* can't auto unregister ndev using devm_add_action() due to
> * devres release sequence in DD core for DMA
> */
>
> return 0;
> -clean_unregister_notifiers:
> - am65_cpsw_unregister_notifiers(common);
> +
> err_cleanup_ndev:
> am65_cpsw_nuss_cleanup_ndev(common);
>