help w/panic under heavy load - 5.4

[Edwin]

Hi John,

Re-compiled with INVARIANTS/INVARIANT_SUPPORT included the gdb output below - same situation (put heavy load 
on the box - incidentally - small (68 byte UDP packets) - fwiw.

my buildkernel kept failing on the options DDB (even tried GENERIC kernel) - so I'm 
sure I'm doing something wrong there - just didn't figure it out yet.

I wanted to get back to you with the output for the above asap though - I'm happy to input/output whatever commands
you would like if necc.

Thanks!
/Edwin


mbsd05# kgdb kernel.debug /tmp/crash/vmcore.5
[GDB will not be able to debug user-mode threads: /usr/lib/libthread_db.so: Undefined symbol "ps_pglobal_lookup"]
GNU gdb 6.1.1 [FreeBSD]
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welcome to change it and/or distribute copies of it under certain conditions.
Type "show copying" to see the conditions.
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This GDB was configured as "i386-marcel-freebsd".
#0  doadump () at pcpu.h:159
159             __asm __volatile("movl %%fs:0,%0" : "=r" (td));
(kgdb) where
#0  doadump () at pcpu.h:159
#1  0xc060c474 in boot (howto=260) at /usr/src/sys/kern/kern_shutdown.c:410
#2  0xc060c6f2 in panic (fmt=0xc081e5ad "m_copym, offset > size of mbuf chain") at /usr/src/sys/kern/kern_shutdown.c:566
#3  0xc063beb8 in m_copym (m=0x0, off0=1500, len=1480, wait=1) at /usr/src/sys/kern/uipc_mbuf.c:385
#4  0xc06996b4 in ip_fragment (ip=0xc124400e, m_frag=0xc7692c38, mtu=-1056768768, if_hwassist_flags=0, sw_csum=1)
    at /usr/src/sys/netinet/ip_output.c:967
#5  0xc069132e in ip_fastforward (m=0xc120e700) at /usr/src/sys/netinet/ip_fastfwd.c:572
#6  0xc066cd99 in ether_demux (ifp=0xc0f90000, m=0xc120e700) at /usr/src/sys/net/if_ethersubr.c:770
#7  0xc066cb1d in ether_input (ifp=0xc0f90000, m=0xc120e700) at /usr/src/sys/net/if_ethersubr.c:631
#8  0xc0711597 in sis_rxeof (sc=0xc0f90000) at /usr/src/sys/pci/if_sis.c:1636
#9  0xc071185f in sis_poll (ifp=0xc0f90000, cmd=POLL_ONLY, count=0) at /usr/src/sys/pci/if_sis.c:1769
#10 0xc05f2f5c in netisr_poll () at /usr/src/sys/kern/kern_poll.c:384
#11 0xc0673cc5 in swi_net (dummy=0x0) at /usr/src/sys/net/netisr.c:338
#12 0xc05fb10c in ithread_loop (arg=0xc0ec6480) at /usr/src/sys/kern/kern_intr.c:547
#13 0xc05fa580 in fork_exit (callout=0xc05fafe8 <ithread_loop>, arg=0xc0ec6480, frame=0xc7692d48)
    at /usr/src/sys/kern/kern_fork.c:791
#14 0xc07a26cc in fork_trampoline () at /usr/src/sys/i386/i386/exception.s:209
(kgdb) f 4
#4  0xc06996b4 in ip_fragment (ip=0xc124400e, m_frag=0xc7692c38, mtu=-1056768768, if_hwassist_flags=0, sw_csum=1)
    at /usr/src/sys/netinet/ip_output.c:967
967                     m->m_next = m_copy(m0, off, len);
(kgdb) f 3
#3  0xc063beb8 in m_copym (m=0x0, off0=1500, len=1480, wait=1) at /usr/src/sys/kern/uipc_mbuf.c:385
385                     KASSERT(m != NULL, ("m_copym, offset > size of mbuf chain"));
(kgdb) quit
mbsd05# 




John Baldwin (jhb at FreeBSD.org) wrote:
> On Monday 18 July 2005 11:42 pm, Edwin wrote:
> > Hi,
> >
> > I have a recurring (re-producible) panic on the 5.3/5.4 kernels and I would
> > like to ask for some help in tracking it down. :) - it could be some
> > misconfig on my part - but i have tried several different configs of the
> > kernel - ultimately w/ polling on/off, ipfw on/off, ipfastforwarding on/off
> > - although with ipff off - the box still crashes but in a different
> > location - it will even crash w/ GENERIC kernel under heavy load.
> >
> > I'm not quite sure where to look past the below (ie. what variables/etc to
> > present to the list).
> 
> Try turning INVARIANTS and INVARIANT_SUPPORT on in your kernel and see if you 
> can reproduce this.  Also, try to get a traceback in ddb if possible as 
> sometimes ddb gives more reliable stack traces.  It looks like your m is 
> NULL, in which case the KASSERT() on the previous line should fire if 
> INVARIANTS is on.
> 
> -- 
> John Baldwin <jhb at FreeBSD.org>  <><  http://www.FreeBSD.org/~jhb/
> "Power Users Use the Power to Serve"  =  http://www.FreeBSD.org