9600 LDT still not happy under KPTI

@@ -19,11 +19,11 @@
  * CDDL HEADER END
  */
 
 /*
  * Copyright (c) 1988, 2010, Oracle and/or its affiliates. All rights reserved.
- * Copyright 2017 Joyent, Inc.
+ * Copyright 2018 Joyent, Inc.
  */
 
 /*      Copyright (c) 1984, 1986, 1987, 1988, 1989 AT&T */
 /*        All Rights Reserved   */
 

@@ -299,11 +299,12 @@
         /*
          * LDT support.
          */
         kmutex_t        p_ldtlock;      /* protects the following fields */
         user_desc_t     *p_ldt;         /* Pointer to private LDT */
-        system_desc_t   p_ldt_desc;     /* segment descriptor for private LDT */
+        uint64_t        p_unused1;      /* no longer used */
+        uint64_t        p_unused2;      /* no longer used */
         ushort_t        p_ldtlimit;     /* highest selector used */
 #endif
         size_t p_swrss;                 /* resident set size before last swap */
         struct aio      *p_aio;         /* pointer to async I/O struct */
         struct itimer   **p_itimer;     /* interval timers */