callback-rxcon-protection-
20031114
FIXES 2498
CheckHost() sets the HOSTDELETED flag on a host, does its
touch, calls H_UNLOCK at the end of its function;
AddCallBCal1 in a different thread grabs the lock, does its
thing. Gets to GetSomeSpace_r(), which calls
h_Enumerate_r; the host in question isn't held, so
h_Enumerate_r calls h_Hold_r and h_Release_r on the host
that CheckHost() set the HOSTDELETED flag on; h_Release_r
sees the HOSTDELETED flag and calls h_TossStuff_r, poof, we
have our broken host entry for ClearHostCallbacks_r to trip