Be far more judicious in the use of curzone-using macros.

*** 932,949 ****
--- 932,956 ----
   */
  #define ZONE_SPECIALPID(x)       ((x) == 0 || (x) == 1)
  
  /*
   * The root vnode of the current zone.
+  *
+  * NOTE: It may be necessary (initialization time for file sharing where an
+  * NGZ loads a file-sharing kernel module that does zsd initialization) to NOT
+  * use this macro. One should ASSERT() that curzone == active ZSD (an
+  * ASSERTion that's not always true at ZSD initialization time) during regular
+  * use of this macro.
   */
  #define ZONE_ROOTVP()   (curzone->zone_rootvp)
  
  /*
   * Since a zone's root isn't necessarily an actual filesystem boundary
   * (i.e. VROOT may not be set on zone->zone_rootvp) we need to not assume it.
   * This macro helps in checking if a vnode is the current zone's rootvp.
   * NOTE:  Using the VN_ prefix, even though it's defined here in zone.h.
+  * NOTE2: See above warning about ZONE_ROOTVP().
   */
  #define VN_IS_CURZONEROOT(vp)   (VN_CMP(vp, ZONE_ROOTVP()))
  
  /*
   * Zone-safe version of thread_create() to be used when the caller wants to