Stack backtrace

I've been having some problems with cvsup corruption and haven't been able
to trace it to the source so I decided to recompile my kernel with all
GENERIC options and debugging to see if it was something that I had changed
that caused the problem. I'm not sure what this means but it popped up
during the build of cvsup. 

Is this a possible source of my problem or is this something not to worry
about?

malloc(M_WAITOK) of "Mbuf", forcing M_NOWAIT with the following
non-sleepable locks held:
exclusive sleep mutex inp (tcpinp) r = 0 (0xc1d17bd0) locked _at_
/usr/src/sys/netinet/tcp_usrreq.c:1037
Stack backtrace:
witness_warn(5,0,c08db91d,c08c1095,c08c5805) at witness_warn+0x194
uma_zalloc_arg(c1021b00,d6b19c0c,2,c066635e,0) at uma_zalloc_arg+0x50
ip_ctloutput(c284213c,d6b19cb8,c08ce5cb,40e,c1d17bd0) at ip_ctloutput+0x9b
tcp_ctloutput(c284213c,d6b19cb8,0,0,0) at tcp_ctloutput+0xad
sosetopt(c284213c,d6b19cb8,d6b19cb4,0,c284213c) at sosetopt+0x48
setsockopt(c1d4ddc0,d6b19d14,14,d6b19d48,5) at setsockopt+0xd4
syscall(2f,2f,2f,281a6920,3) at syscall+0x12f
Xint0x80_syscall() at Xint0x80_syscall+0x1f
--- syscall (105), eip = 0x28108fef, esp = 0xbfbfe91c, ebp = 0xbfbfe948 ---