Subject: Re: [PATCH net-next v2 1/8] net: rtnetlink: add RTM_FLUSHNEIGH

From: David Ahern <[email-masked]>
Date: Mon, 11 Apr 2022 16:57:43 -0600

On Mon, Apr 11, 2022 at 08:29:27PM +0300, Nikolay Aleksandrov wrote:
> Add a new rtnetlink type used to flush neigh objects. It will be
> initially used to add flush with filtering support for bridge fdbs, but
> it also opens the door to add similar support to others (e.g. vxlan).
> 
> Signed-off-by: Nikolay Aleksandrov <[email-masked]>
> ---
>  include/uapi/linux/rtnetlink.h | 3 +++
>  security/selinux/nlmsgtab.c    | 3 ++-
>  2 files changed, 5 insertions(+), 1 deletion(-)
> 
> diff --git a/include/uapi/linux/rtnetlink.h b/include/uapi/linux/rtnetlink.h
> index 83849a37db5b..06001cfd404b 100644
> --- a/include/uapi/linux/rtnetlink.h
> +++ b/include/uapi/linux/rtnetlink.h
> @@ -194,6 +194,9 @@ enum {
>  	RTM_GETTUNNEL,
>  #define RTM_GETTUNNEL	RTM_GETTUNNEL
>  
> +	RTM_FLUSHNEIGH = 124,
> +#define RTM_FLUSHNEIGH	RTM_FLUSHNEIGH
> +

rtm message types are "new, del, get, set" quadruplets; making this a
flush breaks the current consistent style. Can this be done by adding
a FLUSH flag to the RTM_DELNEIGH message?

>  	__RTM_MAX,
>  #define RTM_MAX		(((__RTM_MAX + 3) & ~3) - 1)
>  };