From mboxrd@z Thu Jan  1 00:00:00 1970
From: David Miller <davem@davemloft.net>
Subject: Re: [PATCH 09/15] ipv4: Cache output routes in fib_info nexthops.
Date: Thu, 19 Jul 2012 08:52:29 -0700 (PDT)
Message-ID: <20120719.085229.2014129813204637207.davem@davemloft.net>
References: <20120718.112404.1910372180742347127.davem@davemloft.net>
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In a dream I found a bug in this patch and the next one.

When we fetch a cached route from the FIB info, we have to
check if it has been invalidated by a PMTU event or similar.
And if so, cmpxchg() it with NULL and release it, so we
can build and install a new cached route there.

I'll fix this up when I integrate everyone's feedback later
today.