Re: [PATCH RESEND net-next v3 2/2] tcp: add LINUX_MIB_PAWS_TW_REJECTED counter

Eric Dumazet
2025-04-08T14:19:00Z

On Mon, Apr 7, 2025 at 4:00 PM Jiayuan Chen <jiayuan.chen@linux.dev> wrote:
>
> When TCP is in TIME_WAIT state, PAWS verification uses
> LINUX_PAWSESTABREJECTED, which is ambiguous and cannot be distinguished
> from other PAWS verification processes.
>
> Moreover, when PAWS occurs in TIME_WAIT, we typically need to pay special
> attention to upstream network devices, so we added a new counter, like the
> existing PAWS_OLD_ACK one.

I really dislike the repetition of "upstream network devices".

Is it mentioned in some RFC ?

>
> Also we update the doc with previously missing PAWS_OLD_ACK.
>
> usage:
> '''
> nstat -az | grep PAWSTimewait
> TcpExtPAWSTimewait 1 0.0
> '''
>
> Suggested-by: Eric Dumazet <edumazet@google.com>
> Signed-off-by: Jiayuan Chen <jiayuan.chen@linux.dev>

Reviewed-by: Eric Dumazet <edumazet@google.com>