From mboxrd@z Thu Jan 1 00:00:00 1970 From: "David S. Miller" Subject: Re: BUG: dst underflow (again) Date: Thu, 4 Nov 2004 22:18:01 -0800 Message-ID: <20041104221801.584c8f11.davem@davemloft.net> References: <4178AB0D.6060107@pobox.com> <20041022.155159.98771450.yoshfuji@linux-ipv6.org> <20041022075947.GA15795@xi.wantstofly.org> <1099577717.1039.155.camel@jzny.localdomain> Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Cc: buytenh@wantstofly.org, yoshfuji@linux-ipv6.org, jgarzik@pobox.com, netdev@oss.sgi.com Return-path: To: hadi@cyberus.ca In-Reply-To: <1099577717.1039.155.camel@jzny.localdomain> Sender: netdev-bounce@oss.sgi.com Errors-to: netdev-bounce@oss.sgi.com List-Id: netdev.vger.kernel.org On 04 Nov 2004 09:15:17 -0500 jamal wrote: > Could you turn off netfilter and see if this continues to happen? That's one possible angle, but let's look at the tracepoints more closely. BTW Lennert, the decoded addresses are extremely helpful. Thanks. Jeff, could you similarly decode the ones that you seem to get? That would be an incredibly useful datapoint. If you've provided this already, my bad and please point me at where you posted that. > > BUG: dst underflow -1: 3bcf9a80 at 42350024 > > BUG: dst underflow 0: 3bcf9a80 at 423486d2 > > BUG: dst underflow 0: 3bcf9a80 at 4235823d ... > > 0x42350024 - 0x42345000 = 0xb024, corresponds to: > > 0000affa > > > > 0x423486d2 - 0x42345000 = 0x36d2, corresponds to: > > 0000339d > > > > 0x4235823d - 0x42345000 = 0x1323d, corresponds to: > > 00012c0d (god, that's one big function btw) The last one is the most interesting. The only dst_release() call that occurs in udpv6_sendmsg() is when xfrm_lookup() returns an error. The semantics of that function are a complete mess (when it errors, it sometimes releases the DST, sometimes does not) and I'll fix that up. But let me ask, do you have any IPSEC policies in the kernel when these BUGs trigger? If so, I'm pretty sure I know what the problem may be.