From owner-freebsd-net@freebsd.org Wed Dec 9 19:18:22 2015 Return-Path: Delivered-To: freebsd-net@mailman.ysv.freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:1900:2254:206a::19:1]) by mailman.ysv.freebsd.org (Postfix) with ESMTP id 66EA39D6026 for ; Wed, 9 Dec 2015 19:18:22 +0000 (UTC) (envelope-from evidence@nitrology.com) Received: from nitrology.com (nitrology.com [69.28.133.242]) by mx1.freebsd.org (Postfix) with ESMTP id 575F31ED6; Wed, 9 Dec 2015 19:18:22 +0000 (UTC) (envelope-from evidence@nitrology.com) Received: by nitrology.com (Postfix, from userid 1001) id EB9799CC9F; Wed, 9 Dec 2015 12:18:15 -0700 (MST) Date: Wed, 9 Dec 2015 12:18:15 -0700 From: Jason Wolfe To: Kubilay Kocak Cc: "Andrey V. Elsukov" , freebsd-net@freebsd.org, Mark Johnston , kevin.bowling@kev009.com, hiren@strugglingcoder.info Subject: Re: Multiple cores/race conditions in IPv6 RA Message-ID: <20151209191815.GA56497@nitrology.com> References: <50cff74ea38f155ae616cf49f5ffb5ae@m.nitrology.com> <5667EA3A.8050200@FreeBSD.org> <5667EC45.2050808@FreeBSD.org> <5667ED4C.90405@FreeBSD.org> <5667FC48.5090507@FreeBSD.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <5667FC48.5090507@FreeBSD.org> User-Agent: Mutt/1.5.24 (2015-08-30) X-BeenThere: freebsd-net@freebsd.org X-Mailman-Version: 2.1.20 Precedence: list List-Id: Networking and TCP/IP with FreeBSD List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Wed, 09 Dec 2015 19:18:22 -0000 Word around town is Kubilay Kocak leaked this on Wed, Dec 09, 2015 at 09:02:48PM +1100: > On 9/12/2015 7:58 PM, Andrey V. Elsukov wrote: > > On 09.12.15 11:54, Kubilay Kocak wrote: > >>> 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. > >>> > >> > >> Is it worth creating an issue report to track/resolve this, with 10.3 > >> coming up? > > > > This problem exists since 4.x-5.x, so, I don't think that creating a > > report will automatically resolve it :) > > > > Not automatically no. But perhaps never being tracked has contributed to > its non-resolution? Andrey/Kubilay, Thanks for the responses. I was actually able to grab 2 patches from markj that we are currently testing. The first is actually in Phab, maybe we can bribe markj to pick it back up :) https://reviews.freebsd.org/D2254 The second one actually gets into the NDP code and is similar to the one posted on the mailing list that you linked. It's a few months newer from May of 2013: https://people.freebsd.org/~markj/patches/ndp-locking.diff Initial testing is going well, I'll report back once we have more conclusive results. It appears based various threads and reviews that the issues are a bit nebulous as there are many locking issues in this code. Thank you to markj and others for going after the hot spots, and I've created a bug report to track the overall progress of this: https://bugs.freebsd.org/bugzilla/show_bug.cgi?id=205165 Also, I don't believe these issues have been present for too long. I see the entry deletion bug reported on 4.X/5.X, and that seems to be more related to the ndp binary itself. Our 8.3-RELEASE installs did not exhibit the race conditions in the kernel code. Thanks again! Jason