From mboxrd@z Thu Jan  1 00:00:00 1970
From: David Miller <davem@davemloft.net>
Subject: Re: [PATCH net-next] ipv6: perform inetpeer binding at dst
 creation, with readonly option
Date: Thu, 08 Mar 2012 13:40:57 -0800 (PST)
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From: Nick Jones <nick.jones@network-box.com>
Date: Fri, 09 Mar 2012 00:10:29 +0800

> However, seeing a kmalloc done for such a transient, sparse
> structure didn't sit so well in the stomach.  If we can be sure that
> the metrics of a dst for an icmp6 packet won't be written to, we
> could use the static const ip6_template_metrics array defined in
> route.c:~205, it has RTAX_HOPLIMIT fixed at 255, and using it avoids
> a kmalloc.
> 
> I'll produce another patch for this strategy if you think this is a
> better idea.

This could work, but you'll need to add an assertion or similar to make
sure this requirement always holds.