From mboxrd@z Thu Jan  1 00:00:00 1970
From: Eric Dumazet <eric.dumazet@gmail.com>
Subject: Re: [PATCH net-next 3/7] net: rxrpc: change call to
 sock_recv_ts_and_drops() on rxrpc recvmsg to sock_recv_timestamp()
Date: Thu, 26 Feb 2015 06:31:06 -0800
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Cc: David Miller <davem@davemloft.net>,
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	Eric Dumazet <edumazet@google.com>,
	Shmulik Ladkani <shmulik.ladkani@gmail.com>,
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To: Eyal Birger <eyal.birger@gmail.com>
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On Thu, 2015-02-26 at 09:30 +0200, Eyal Birger wrote:

> Maybe I didn't understand your comment. Note this patch does not fix
> SO_RXQ_OVFL on rxrpc sockets.
> 
> I essentially reverted 3b885787ea4112 for these sockets.
> 
> It may be possible to compact rxrpc skb->cb[] usage by tricking the size
> of the resend_at variable as you suggested.
> 
> However, since SO_RXQ_OVFL never really worked on these sockets,
> I limited the patch series scope to moving skb->dropcount; This patch only
> signals that rxrpc can't support this feature unless some space is freed in its
> skb->cb[] use.
> --

My point is : If you stick this patch early in the serie, then skb->mark
will be overwritten by sock_recv_timestamp() (to store skb->dropcount)
and rxrpc breaks as it actively relies on skb->mark (apparently)

We dont care if SO_RXQ_OVFL is broken for rxprpc : Nobody noticed yet.

But breaking rxrpc skb->mark early in the serie does not help bisection
if needed later.