Date: Wed, 10 Nov 2004 12:10:28 +0100 From: Sebastian Schulze Struchtrup <sebastian@struchtrup.de> To: Robert Watson <rwatson@freebsd.org> Cc: Arjan Van Leeuwen <avleeuwen@gmail.com> Subject: Re: Panic in 5.3, related to network traffic Message-ID: <4191F724.2010405@struchtrup.de> In-Reply-To: <Pine.NEB.3.96L.1041110094326.60848U-100000@fledge.watson.org> References: <Pine.NEB.3.96L.1041110094326.60848U-100000@fledge.watson.org>
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>Hmm. Odd. The stack trace in your screen shot shows the same mbuf being
>passed to icmp_error() was was passed to ip_forward(). This suggests,
>given the other arguments, that it's actually the call to icmp_error() on
>line 1650, not 1879. I wonder if addr2line is getting confused.
>
It seems that this is the usual enemy of debugging: compiler optimisation.
There's actually only one call. The call in line 1650 jumps to the one
generated by line 1879.
(line numbers don't match, because I am runnig 6-Current on this machine)
/usr/src/sys/netinet/ip_input.c:1711 (1650)
103a: 6a 00 push $0x0
103c: 6a 00 push $0x0
103e: 6a 01 push $0x1
1040: 6a 03 push $0x3
1042: 56 push %esi
1043: e9 fa fd ff ff jmp e42 <ip_forward+0x1a6>
/usr/src/sys/netinet/ip_input.c:1711 (1650)
e41: 56 push %esi
/usr/src/sys/netinet/ip_input.c:1940 (1879)
e42: e8 fc ff ff ff call e43 <ip_forward+0x1a7>
e47: eb e8 jmp e31 <ip_forward+0x195>
> If you use kgdb on the kernel.debug and do:
>
> l *icmp_error+0x191
> l *ip_forward+0x3d1
>
>Do you get different answers?
>
>
Maybe it would help to compile the kernel with INVARIANTS.
Then we should get a false assertion somewhere earlier and closer to the
problem.
I assume that their is an invalid/null mbuf somewhere. It seems that
this comes more or less directly from the inferface driver.
Just my two cents...
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