Re: [PATCH iproute2] devlink: Support DEVLINK_ESWITCH_MODE_SWITCHDEV_INACTIVE

[David Ahern <dsahern@gmail.com>]

On 11/6/25 5:14 PM, Saeed Mahameed wrote:
> From: Saeed Mahameed <saeedm@nvidia.com>
> 
> Add support for the new inactive switchdev mode [1].
> 
> A user can start the eswitch in switchdev or switchdev_inactive mode.
> 
> Active: Traffic is enabled on this eswitch FDB.
> Inactive: Traffic is ignored/dropped on this eswitch FDB.
> 
> An example use case:
> $ devlink dev eswitch set pci/0000:08:00.1 mode switchdev_inactive
> Setup FDB pipeline and netdev representors
> ...
> Once ready to start receiving traffic
> $ devlink dev eswitch set pci/0000:08:00.1 mode switchdev
> 
> [1] https://lore.kernel.org/all/20251107000831.157375-1-saeed@kernel.org/
> 
> Signed-off-by: Saeed Mahameed <saeedm@nvidia.com>
> ---
>  devlink/devlink.c            | 7 ++++++-
>  include/uapi/linux/devlink.h | 1 +
>  2 files changed, 7 insertions(+), 1 deletion(-)
> 
> diff --git a/devlink/devlink.c b/devlink/devlink.c
> index 35128083..fd9fac21 100644
> --- a/devlink/devlink.c
> +++ b/devlink/devlink.c
> @@ -45,6 +45,7 @@
>  
>  #define ESWITCH_MODE_LEGACY "legacy"
>  #define ESWITCH_MODE_SWITCHDEV "switchdev"
> +#define ESWITCH_MODE_SWITCHDEV_INACTIVE "switchdev_inactive"
>  #define ESWITCH_INLINE_MODE_NONE "none"
>  #define ESWITCH_INLINE_MODE_LINK "link"
>  #define ESWITCH_INLINE_MODE_NETWORK "network"

These modes really should be an array that is used for both set and
show. Then eswitch_mode_get and eswitch_mode_get would not need to be
touched; just update arrays and the new entries take effect.

> @@ -1428,6 +1429,8 @@ static int eswitch_mode_get(const char *typestr,
>  		*p_mode = DEVLINK_ESWITCH_MODE_LEGACY;
>  	} else if (strcmp(typestr, ESWITCH_MODE_SWITCHDEV) == 0) {
>  		*p_mode = DEVLINK_ESWITCH_MODE_SWITCHDEV;
> +	} else if (strcmp(typestr, ESWITCH_MODE_SWITCHDEV_INACTIVE) == 0) {
> +		*p_mode = DEVLINK_ESWITCH_MODE_SWITCHDEV_INACTIVE;
>  	} else {
>  		pr_err("Unknown eswitch mode \"%s\"\n", typestr);
>  		return -EINVAL;
> @@ -2848,7 +2851,7 @@ static bool dl_dump_filter(struct dl *dl, struct nlattr **tb)
>  static void cmd_dev_help(void)
>  {
>  	pr_err("Usage: devlink dev show [ DEV ]\n");
> -	pr_err("       devlink dev eswitch set DEV [ mode { legacy | switchdev } ]\n");
> +	pr_err("       devlink dev eswitch set DEV [ mode { legacy | switchdev | switchdev_inactive } ]\n");
>  	pr_err("                               [ inline-mode { none | link | network | transport } ]\n");
>  	pr_err("                               [ encap-mode { none | basic } ]\n");
>  	pr_err("       devlink dev eswitch show DEV\n");
> @@ -3284,6 +3287,8 @@ static const char *eswitch_mode_name(uint32_t mode)
>  	switch (mode) {
>  	case DEVLINK_ESWITCH_MODE_LEGACY: return ESWITCH_MODE_LEGACY;
>  	case DEVLINK_ESWITCH_MODE_SWITCHDEV: return ESWITCH_MODE_SWITCHDEV;
> +	case DEVLINK_ESWITCH_MODE_SWITCHDEV_INACTIVE:
> +		return ESWITCH_MODE_SWITCHDEV_INACTIVE;
>  	default: return "<unknown mode>";
>  	}
>  }
> diff --git a/include/uapi/linux/devlink.h b/include/uapi/linux/devlink.h
> index bcd5fde1..317c088b 100644
> --- a/include/uapi/linux/devlink.h
> +++ b/include/uapi/linux/devlink.h
> @@ -181,6 +181,7 @@ enum devlink_sb_threshold_type {
>  enum devlink_eswitch_mode {
>  	DEVLINK_ESWITCH_MODE_LEGACY,
>  	DEVLINK_ESWITCH_MODE_SWITCHDEV,
> +	DEVLINK_ESWITCH_MODE_SWITCHDEV_INACTIVE,
>  };
>  
>  enum devlink_eswitch_inline_mode {

uapi changes should be a separate patch that I can drop when applying
the rest of the changes.

Requests for future patches; i applied this one to iproute2-next.