DF-5593 run log (guest serial/dmesg capture; rig = ptsim3.ko mode 3):

+ kldload /root/df5592/ptsim3/ptsim3.ko
+ sleep 2
+ sysctl debug.ptsim3.noattach=1
+ vmstat -m > /root/df5592/vmstat_before.txt
+ sysctl debug.ptsim3.scan=1
+ sleep 3
+ sysctl debug.ptsim3.ios debug.ptsim3.ccbs
debug.ptsim3.ios: 64
debug.ptsim3.ccbs: 8
+ sysctl debug.ptsim3.go=3
[PTSIM3] DF-5593: sim->ccb_count=8, ccb_freeq length=8 (each orphaned union ccb ~720 bytes + callout, M_CAMXPT)
[PTSIM3] DF-5593: clean detach (deregister+free): the 8 pooled ccbs are NOT freed by cam_sim_free()
[PTSIM3] DF-5593: detach DONE; 8 ccbs orphaned -- check 'vmstat -m | grep -i xpt' delta
+ sleep 2
+ vmstat -m > /root/df5592/vmstat_after.txt

vmstat -m (CAM malloc types):
  before: CAM_XPT  40  7.71K   0  390M  275
  after:  CAM_XPT  69  19.2K   0  390M  453
  (count/in-use never returns after the detach; the 8 pooled ccbs plus
   scan allocations stay orphaned; no free of ccb_freeq members occurs)