Date: Wed, 9 Dec 2015 11:45:46 +0300 From: "Andrey V. Elsukov" <ae@FreeBSD.org> To: Jason <j@scre.ws>, freebsd-net@freebsd.org Cc: kevin.bowling@kev009.com, hiren@strugglingcoder.info, Mark Johnston <markj@freebsd.org> Subject: Re: Multiple cores/race conditions in IPv6 RA Message-ID: <5667EA3A.8050200@FreeBSD.org> In-Reply-To: <50cff74ea38f155ae616cf49f5ffb5ae@m.nitrology.com> References: <50cff74ea38f155ae616cf49f5ffb5ae@m.nitrology.com>
next in thread | previous in thread | raw e-mail | index | archive | help
This is an OpenPGP/MIME signed message (RFC 4880 and 3156) --CA3LqJI7WbNHHaADAAf5o3jSFhroLgeMh Content-Type: text/plain; charset=windows-1252 Content-Transfer-Encoding: quoted-printable On 08.12.15 08:32, Jason wrote: > Hi, >=20 > It appears the IPv6 router advertisement code paths were written fairly= > lockless, assuming you would never process multiples concurrently. We > are seeing multiple page faults in various places processing the > messages and modifying the routing table. We have multiple L3 devices > and multiple v6 blocks broadcasting these messages to hardware with dua= l > uplinks in the same VLAN, which I believe is making us susceptible to > this. Though I believe the dual uplink is all that's required for this= , > as it can be seen in configurations with a single v6 block. >=20 > We are running stable/10 @ r285800, and it doesn't appear anything > relevant has changed since then. Our other widely deployed version is > 8.3-RELEASE, which does not see this issue. Upon bumping a machine fro= m > 8.3 -> 10 we can see it start to exhibit this behavior. The only chang= e > I see that might be relevant is r243148, but these cores are relatively= > rare, so testing is tough without a considerable deployment. So > basically I'm hoping someone with a trained eye can send us in the righ= t > direction before we go down that road. Hi, some time ago Mark Johnston has published there the patch related to this problem: https://lists.freebsd.org/pipermail/freebsd-net/2013-February/034682.html= Maybe Mark has something to say about it. --=20 WBR, Andrey V. Elsukov --CA3LqJI7WbNHHaADAAf5o3jSFhroLgeMh Content-Type: application/pgp-signature; name="signature.asc" Content-Description: OpenPGP digital signature Content-Disposition: attachment; filename="signature.asc" -----BEGIN PGP SIGNATURE----- Version: GnuPG v2 Comment: Using GnuPG with Thunderbird - http://www.enigmail.net/ iQEcBAEBCAAGBQJWZ+o6AAoJEAHF6gQQyKF6pvgH/iD6n22BzWnTli+pnOc4GkyV UqHl5cnNb6qpZBHJ57zjw4sPubjkog1GaoTDKqMFmXkJ1YjWaMvAQ1XXmdH3Yz4b SV9tOuQUqasI+Pd6d/0u9DwJdnHV17BtvauBr9Ld9u4zL3kEaUpLIY6hIzobRFUv /YKq3mIr5KzrCKwGu6YGcV3Jyiqx8MLOIj07kovllGYMhIe0aaCU034ydIWOlTGR bvuRCXh2eJKMvj+rCozYxOCIfTPZY8gA9tKgu9CwNvfRA9XMdMEiCgnt7NPC0RQV ecmeH6/BU+GpnuNpxjSnKlIW73ipdRFo6bd3/7O7SDXWooU7T407iV2ndzz9hKw= =ZXQo -----END PGP SIGNATURE----- --CA3LqJI7WbNHHaADAAf5o3jSFhroLgeMh--
Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?5667EA3A.8050200>