5.99.55 panic

[Aleksey Cheusov <cheusov%tut.by@localhost>]

About 2 day ago I updated my system to latest current.
Now I see the kernel panic a few minutes after
running a pkgsrc bulk build. Stack trace is below.

Any clue?

breakpoint() at netbsd:breakpoint+0x5
panic() at netbsd:panic+0x219
lockdebug_abort() at netbsd:lockdebug_abort+0x3a
rw_vector_enter() at netbsd:rw_vector_enter+0x32c
genfs_lock() at netbsd:genfs_lock+0x9f
layer_bypass() at netbsd:layer_bypass+0xf5
VOP_LOCK() at netbsd:VOP_LOCK+0x32
vclean() at netbsd:vclean+0x95
getcleanvnode() at netbsd:getcleanvnode+0xfc
getnewvnode() at netbsd:getnewvnode+0x1b2
layer_node_alloc() at netbsd:layer_node_alloc+0x34
layer_node_create() at netbsd:layer_node_create+0x8b
layer_lookup() at netbsd:layer_lookup+0x9c
VOP_LOOKUP() at netbsd:VOP_LOOKUP+0x39
lookup_once() at netbsd:lookup_once+0xd4
namei_tryemulroot() at netbsd:namei_tryemulroot+0x253
namei() at netbsd:namei+0x2b
vn_open() at netbsd:vn_open+0x92
sys_open() at netbsd:sys_open+0xeb
syscall() at netbsd:syscall+0xac