Yet another LOR: vm object/system map

This particular LOR happened upon getting out of swap.
My knowledge is insufficient to tell if it's a sign of
a real problem or just a false positive.

swap_pager: out of swap space
swap_pager_getswapspace(16): failed
lock order reversal
 1st 0xc2e17d4c vm object (vm object) _at_ /usr/src/sys/vm/vnode_pager.c:1120
 2nd 0xc0c2f110 system map (system map) _at_ /usr/src/sys/vm/vm_kern.c:328
Stack backtrace:
backtrace(c05ca039,c0c2f110,c05d4ecc,c05d4ecc,c05d4d63) at backtrace+0x17
witness_lock(c0c2f110,8,c05d4d63,148,1263) at witness_lock+0x672
_mtx_lock_flags(c0c2f110,0,c05d4d63,148,3) at _mtx_lock_flags+0xba
_vm_map_lock(c0c2f0b0,c05d4d63,148,2b4,c061eec0) at _vm_map_lock+0x36
kmem_malloc(c0c2f0b0,1000,101,cc3e7ac8,c056cd93) at kmem_malloc+0x3a
page_alloc(c0c3a3c0,1000,cc3e7abb,101,c0618978) at page_alloc+0x27
slab_zalloc(c0c3a3c0,1,c05d66bc,68c,0) at slab_zalloc+0xb3
uma_zone_slab(c0c3a3c0,1,c05d66bc,68c,0) at uma_zone_slab+0xd6
uma_zalloc_internal(c0c3a3c0,0,1,0,c0c212f0) at uma_zalloc_internal+0x3e
bucket_alloc(80,1,c05d66bc,70b,0) at bucket_alloc+0x65
uma_zfree_arg(c0c21240,cbd31000,0,7b6,80000000) at uma_zfree_arg+0x2c6
swp_pager_meta_ctl(c2e17d4c,0,0,2,cc3e7cbc) at swp_pager_meta_ctl+0x10f
swap_pager_unswapped(c0c49a90,1,c05c0291,bd,cc3e7c54) at swap_pager_unswapped+0x
2a
vm_fault(c1135ccc,80f3000,2,8,c249b980) at vm_fault+0x1217
trap_pfault(cc3e7d48,1,80f30f4,27f,80f30f4) at trap_pfault+0x109
trap(2f,2f,2f,52ed,80f30f0) at trap+0x1fc
calltrap() at calltrap+0x5
--- trap 0xc, eip = 0x80561e0, esp = 0xbfbff650, ebp = 0xbfbff668 ---

-- 
Yar