MBUFTRACE panic (KASSERT off < percpu_nextoff)

[Manuel Bouyer <bouyer%antioche.eu.org@localhost>]

Hello,
trying to debug
http://mail-index.netbsd.org/current-users/2014/03/26/msg024535.html
I built a kernel with MBUFTRACE (this is netbsd-6 of december).
I got this almost immediatly:

panic: kernel diagnostic assertion "off < percpu_nextoff" failed: file 
"../../.. /../kern/subr_percpu.c", line 76 
cpu0: Begin traceback...
kern_assert() at netbsd:kern_assert+0x48
percpu_offset() at netbsd:percpu_offset+0x4b
percpu_getref() at netbsd:percpu_getref+0x40
m_claim() at netbsd:m_claim+0x44
m_claimm() at netbsd:m_claimm+0x1d
ether_input() at netbsd:ether_input+0x33
carp_input() at netbsd:carp_input+0x7f
ether_input() at netbsd:ether_input+0x1c4
ether_input() at netbsd:ether_input+0x3c7
wm_intr() at netbsd:wm_intr+0x40e
intr_biglock_wrapper() at netbsd:intr_biglock_wrapper+0x1d
Xintr_ioapic_level1() at netbsd:Xintr_ioapic_level1+0xf2
--- interrupt ---
x86_pause() at netbsd:x86_pause+0x2
callout_softclock() at netbsd:callout_softclock+0x390
softint_dispatch() at netbsd:softint_dispatch+0xd9
DDB lost frame for netbsd:Xsoftintr+0x4f, trying 0xfffffe800100fd70
Xsoftintr() at netbsd:Xsoftintr+0x4f
--- interrupt ---

any idea ?

-- 
Manuel Bouyer <bouyer%antioche.eu.org@localhost>
     NetBSD: 26 ans d'experience feront toujours la difference
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