From mboxrd@z Thu Jan  1 00:00:00 1970
From: David Miller <davem@davemloft.net>
Subject: Re: [PATCH net-next] ipv4: fix a dst leak in tunnels
Date: Thu, 16 Jan 2014 17:13:03 -0800 (PST)
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From: Eric Dumazet <eric.dumazet@gmail.com>
Date: Thu, 16 Jan 2014 16:41:19 -0800

> This patch :
> 
> 1) Remove a dst leak if DST_NOCACHE was set on dst
>    Fix this by holding a reference only if dst really cached.

Can you explain this problem a little bit more?

Why do we have to handle DST_NOCACHE specially?  We hold a reference
and dst_release() knows what to do with DST_NOCACHE routes.

Or is it semantically undesirable for tunnels to cache these routes?
If so, why do we leave sockets caching DST_NOCACHE routes just fine?

Thanks.