Hi again.
-----Original Message----- From: stable-owner@vger.kernel.org [mailto:stable-owner@vger.kernel.org] On Behalf Of Nobuhiro Iwamatsu Sent: Monday, June 10, 2019 10:10 AM To: Greg Kroah-Hartman gregkh@linuxfoundation.org Cc: linux-kernel@vger.kernel.org; stable@vger.kernel.org; Alan Maguire alan.maguire@oracle.com; David Ahern dsahern@gmail.com; David S. Miller davem@davemloft.net Subject: Re: [PATCH 4.14 03/35] neighbor: Call __ipv4_neigh_lookup_noref in neigh_xmit
Hi,
On Sun, Jun 09, 2019 at 06:42:09PM +0200, Greg Kroah-Hartman wrote:
From: David Ahern dsahern@gmail.com
[ Upstream commit 4b2a2bfeb3f056461a90bd621e8bd7d03fa47f60 ]
Commit cd9ff4de0107 changed the key for IFF_POINTOPOINT devices to INADDR_ANY but neigh_xmit which is used for MPLS encapsulations was not updated to use the altered key. The result is that every packet
Tx
does a lookup on the gateway address which does not find an entry, a new one is created only to find the existing one in the table right before the insert since arp_constructor was updated to reset the primary key. This is seen in the allocs and destroys counters: ip -s -4 ntable show | head -10 | grep alloc
which increase for each packet showing the unnecessary overhread.
Fix by having neigh_xmit use __ipv4_neigh_lookup_noref for
NEIGH_ARP_TABLE.
Fixes: cd9ff4de0107 ("ipv4: Make neigh lookup keys for loopback/point-to-point devices be INADDR_ANY") Reported-by: Alan Maguire alan.maguire@oracle.com Signed-off-by: David Ahern dsahern@gmail.com Tested-by: Alan Maguire alan.maguire@oracle.com Signed-off-by: David S. Miller davem@davemloft.net Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org
This commit also requires the following commit:
commit 9b3040a6aafd7898ece7fc7efcbca71e42aa8069 Author: David Ahern dsahern@gmail.com Date: Sun May 5 11:16:20 2019 -0700
ipv4: Define __ipv4_neigh_lookup_noref when CONFIG_INET is disabled Define __ipv4_neigh_lookup_noref to return NULL when CONFIG_INET isdisabled.
Fixes: 4b2a2bfeb3f0 ("neighbor: Call __ipv4_neigh_lookup_noref inneigh_xmit") Reported-by: kbuild test robot lkp@intel.com Signed-off-by: David Ahern dsahern@gmail.com Signed-off-by: David S. Miller davem@davemloft.net
And this is also necessary for 4.4.y, 4.14.y, 4.19.y and 5.1.y.
4.4.y, 4.9.y, 4.19.y and 5.1.y.
Please apply this commit.
Best regards, Nobuhiro