rtfree: 0xc5caad98 has 2 refs

Hello,

I have an i386 7.0-PRERELEASE #12: Thu Dec 27 17:46:49 CET 2007, with an 
em and two fxp interfaces in an IPv4-only setup with some jails and a pf 
route-to (if that counts) line.

The machine itself runs some mail related stuff (postfix, cyrus, 
openldap, etc) on a ZFS pool.

The problem is with the default kernel I get tons of similar messages:
Dec 27 12:38:40 artax kernel: rtfree: 0xc5caad98 has 1 refs
Dec 27 12:39:03 artax last message repeated 24 times
Dec 27 12:39:03 artax kernel: rtfree: 0xc5caad98 has 2 refs
Dec 27 12:39:03 artax kernel: rtfree: 0xc5caad98 has 1 refs
Dec 27 12:39:04 artax last message repeated 64 times
Dec 27 12:39:04 artax kernel: rtfree: 0
Dec 27 12:39:04 artax kernel: xc5caad98 has 1 refs
Dec 27 12:39:04 artax kernel:
Dec 27 12:39:04 artax kernel: rtfree: 0xc5caad98
Dec 27 12:39:04 artax kernel: has 1 refs
Dec 27 12:39:04 artax kernel:
Dec 27 12:39:04 artax kernel: rtfree: 0xc5caad98 has 1 refs
Dec 27 12:39:04 artax kernel:
Dec 27 12:39:04 artax kernel: rtfree: 0xc5caad98 h
Dec 27 12:39:04 artax kernel: s 1 refs
Dec 27 12:39:04 artax kernel:
Dec 27 12:39:04 artax kernel: rtfree
Dec 27 12:39:04 artax kernel: 0xc5caad98 has 1 refs

Besides these messages fill up the logs and are annoying, the machine 
crashes minutes after it has been started.
I found out that replacing rtfree() calls in the kernel to 
RTFREE_LOCKED() not only makes the above messages disappear, but helps 
the machine to survive and run for days.

The only places where there are plain rtfree calls are in the kernel 
(and where I've replaced them to RTFREE_LOCKED):
net/route.c
netinet/if_ether.c
netinet6/nd6_nbr.c
netinet6/in6_ifattach.c
netinet6/in6_gif.c

Question: is the above approach right and if it is, do anyone care to 
make this replacement?

BTW, how could I find out what causes these?

-- 
Attila Nagy                                   e-mail: Attila.Nagy_at_fsn.hu
Free Software Network (FSN.HU)                 phone: +3630 306 6758
http://www.fsn.hu/