From mboxrd@z Thu Jan 1 00:00:00 1970 From: Bob Tracy Subject: Re: [BUG] 3.12.0-rcX IPv6 panic Date: Mon, 21 Oct 2013 18:40:41 -0500 Message-ID: <20131021234041.GA12350@gherkin.frus.com> References: <20131021131846.GA5769@gherkin.frus.com> <20131021155252.GA24158@order.stressinduktion.org> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii To: linux-kernel@vger.kernel.org, netdev@vger.kernel.org Return-path: Content-Disposition: inline In-Reply-To: <20131021155252.GA24158@order.stressinduktion.org> Sender: linux-kernel-owner@vger.kernel.org List-Id: netdev.vger.kernel.org On Mon, Oct 21, 2013 at 05:52:52PM +0200, Hannes Frederic Sowa wrote: > On Mon, Oct 21, 2013 at 08:18:46AM -0500, Bob Tracy wrote: > > Actually, a regression: the 3.11 kernel is rock-solid stable on my > > Alpha. > > > > Beginning with 3.12.0-rc1, I can reliably trigger a kernel panic by > > executing the gogo6.net "gw6c" IPv6 client program. If the networking > > layer is active, an "Oops" will eventually (within a day) occur regardless > > of whether I attempt to run "gw6c". 3.12.0-rcX is stable as long as I > > leave networking completely disabled. The error has persisted up through > > -rc6. Apologies for not mentioning this earlier, but the state of my > > PWS-433au has been questionable, and I wanted to make sure I had a > > legitimate bug sighting. > > > > I'll have to transcribe the panic backtrace by hand: nothing makes it > > into any of the system logs :-(. I *can* recall that every backtrace > > I've seen thus far has included one of the skb_copy() variants near the > > top of the list (first or second function). > > Try to capture the panic via serial console. Otherwise a picture > would give us a first hint. Please watch out for lines like > skb_(over|under)_panic. I'll get a screen capture of some kind for you within the next day or so. > gw6c is a tunnel client? Can you post ip -6 tunnel ls? Assuming you meant "show [NAME]" (no "ls" option for the tunnel object), that yields the following with "gw6c" running on a 3.11.0 kernel: smirkin:~# ip -6 tunnel show sit1 sit1: any/ipv6 remote 4056:5874:: local 4500:0:0:4000:4029:: encaplimit 0 hoplimit 0 tclass 0x00 flowlabel 0x00000 (flowinfo 0x00000000) I'm running the gw6c client in gateway mode: the Alpha is my IPv6 gateway/firewall. --Bob