From mboxrd@z Thu Jan  1 00:00:00 1970
From: Eric Dumazet <eric.dumazet@gmail.com>
Subject: Re: [PATCH net-next] net: sock: adapt SOCK_MIN_RCVBUF and
 SOCK_MIN_SNDBUF
Date: Wed, 19 Jun 2013 03:02:12 -0700
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To: Daniel Borkmann <dborkman@redhat.com>
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On Wed, 2013-06-19 at 11:57 +0200, Daniel Borkmann wrote:

> Ok, if you prefer, I can send an update.
> 

Yes please.

By the way, I used exactly :

-#define SOCK_MIN_SNDBUF 2048
+/* minimum tcp skb truesize is 2048 + sizeof(struct sk_buff) */
+#define TCP_SKB_MIN_TRUESIZE (2048 + sizeof(struct sk_buff))
+
+#define SOCK_MIN_SNDBUF (2 * TCP_SKB_MIN_TRUESIZE)


because SKB_TRUESIZE(2048) adds 
SKB_DATA_ALIGN(sizeof(struct skb_shared_info))

But in case of TCP skbs, the skb_shared_info is part of the 2048 bytes
allocation for skb->head