kern/155597: Kernel panics with "sbdrop" message

[Vladimir Kutakov]

>Number:         155597
>Category:       kern
>Synopsis:       Kernel panics with "sbdrop" message
>Confidential:   no
>Severity:       serious
>Priority:       medium
>Responsible:    freebsd-bugs
>State:          open
>Quarter:        
>Keywords:       
>Date-Required:
>Class:          sw-bug
>Submitter-Id:   current-users
>Arrival-Date:   Wed Mar 16 12:30:12 UTC 2011
>Closed-Date:
>Last-Modified:
>Originator:     Vladimir Kutakov
>Release:        7.4 RELEASE
>Organization:
>Environment:
FreeBSD nickel.novoteka.ru 7.4-RELEASE FreeBSD 7.4-RELEASE #0: Wed Mar  9 17:28:54 MSK 2011     prince at nickel.novoteka.ru:/usr/obj/usr/src/sys/GENERIC  amd64
>Description:
The machine works as webserver and has panic "sbdrop" after some hours of work. The network is rather loaded, but not extremly (about 20-30kpps input).

Please let me know if some additional information needed. I want to resolve the problem very much.

Here is the backtrace from the dumped core:
(kgdb) bt
#0  doadump () at pcpu.h:196
#1  0xffffff000706d3a0 in ?? ()
#2  0xffffffff8054d4da in boot (howto=260) at /usr/src/sys/kern/kern_shutdown.c:421
#3  0xffffffff8054d8f2 in panic (fmt=Variable "fmt" is not available.
) at /usr/src/sys/kern/kern_shutdown.c:576
#4  0xffffffff805a9976 in sbdrop_internal (sb=Variable "sb" is not available.
) at /usr/src/sys/kern/uipc_sockbuf.c:843
#5  0xffffffff8069d53c in tcp_do_segment (m=0xffffff01b5618400, th=0xffffff01573e4022, so=0xffffff013eecd2d0, tp=0xffffff016f9f8000, drop_hdrlen=40, tlen=0) at /usr/src/sys/netinet/tcp_input.c:2043
#6  0xffffffff8069ed48 in tcp_input (m=0xffffff01b5618400, off0=Variable "off0" is not available.
) at /usr/src/sys/netinet/tcp_input.c:847
#7  0xffffffff8063a2eb in ip_input (m=0xffffff01b5618400) at /usr/src/sys/netinet/ip_input.c:663
#8  0xffffffff805f2ee1 in ether_demux (ifp=0xffffff00070f5000, m=0xffffff01b5618400) at /usr/src/sys/net/if_ethersubr.c:834
#9  0xffffffff805f315e in ether_input (ifp=0xffffff00070f5000, m=0xffffff01b5618400) at /usr/src/sys/net/if_ethersubr.c:692
#10 0xffffffff8031ddb9 in igb_rxeof (que=Variable "que" is not available.
) at /usr/src/sys/dev/e1000/if_igb.c:4097
#11 0xffffffff8031e1a8 in igb_msix_que (arg=Variable "arg" is not available.
) at /usr/src/sys/dev/e1000/if_igb.c:1309
#12 0xffffffff8052b0e5 in ithread_loop (arg=0xffffff00070fe100) at /usr/src/sys/kern/kern_intr.c:1181
#13 0xffffffff80527b43 in fork_exit (callout=0xffffffff8052af70 <ithread_loop>, arg=0xffffff00070fe100, frame=0xffffff800013fc80) at /usr/src/sys/kern/kern_fork.c:811
#14 0xffffffff80800f3e in fork_trampoline () at /usr/src/sys/amd64/amd64/exception.S:554
#15 0x0000000000000000 in ?? ()
#16 0x0000000000000000 in ?? ()

>How-To-Repeat:
Direct netwotk traffic to the machine and wait some hours.
>Fix:


>Release-Note:
>Audit-Trail:
>Unformatted: