From: Steffen Klassert <steffen.klassert@secunet•com>
To: David Miller <davem@davemloft•net>
Cc: timo.teras@iki•fi, netdev@vger•kernel.org
Subject: Re: linux-3.0.x regression with ipv4 routes having mtu
Date: Tue, 20 Dec 2011 09:03:41 +0100 [thread overview]
Message-ID: <20111220080341.GM6348@secunet.com> (raw)
In-Reply-To: <20111219.150903.108164273331779302.davem@davemloft.net>
On Mon, Dec 19, 2011 at 03:09:03PM -0500, David Miller wrote:
>
> Actually, adding yet another ID is pointless.
>
> Just get rid of redirect_genid, and use net->ipv4.rt_genid for all of
> the necessary purposes.
I already thought about such a solution, but is this really save?
What if somebody adds/deletes/flushes routes? rt_cache_invalidate()
is invoked and we increment net->ipv4.rt_genid. Then an icmp redirect
may appear and we call ip_rt_redirect() which sets the id on the
inetpeer to the new value of net->ipv4.rt_genid. After that,
ipv4_validate_peer() will find the generation id in proper state
and does not invalidate the learned pmtu value.
I think we could either have two separate generation ids for
pmtu and redirect handling, or we could handle both cases together
by accumulating check_peer_redir() and check_peer_pmtu() into a
check_peer() function. But the latter seems to be a bit too extensive
for a simple bug fix.
next prev parent reply other threads:[~2011-12-20 8:03 UTC|newest]
Thread overview: 23+ messages / expand[flat|nested] mbox.gz Atom feed top
2011-12-14 15:54 linux-3.0.x regression with ipv4 routes having mtu Timo Teräs
2011-12-14 17:50 ` David Miller
2011-12-14 17:57 ` Eric Dumazet
2011-12-14 18:22 ` Timo Teräs
2011-12-15 13:49 ` Steffen Klassert
2011-12-16 12:21 ` Steffen Klassert
2011-12-16 14:30 ` Timo Teräs
2011-12-19 13:52 ` Steffen Klassert
2011-12-19 20:09 ` David Miller
2011-12-20 8:03 ` Steffen Klassert [this message]
2011-12-19 21:10 ` David Miller
2011-12-20 6:53 ` Timo Teräs
2011-12-20 7:03 ` David Miller
2011-12-20 7:18 ` Steffen Klassert
2011-12-20 18:35 ` David Miller
2011-12-21 8:56 ` Steffen Klassert
2011-12-21 20:56 ` David Miller
2011-12-22 10:25 ` Steffen Klassert
2011-12-22 18:51 ` David Miller
2011-12-23 8:47 ` Steffen Klassert
2011-12-23 9:00 ` David Miller
2011-12-23 8:58 ` Steffen Klassert
2012-02-02 10:01 ` Steffen Klassert
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