8956 Implement KPTI
Reviewed by: Jerry Jelinek <jerry.jelinek@joyent.com>
Reviewed by: Robert Mustacchi <rm@joyent.com>
9210 remove KMDB branch debugging support
9211 ::crregs could do with cr2/cr3 support
9209 ::ttrace should be able to filter by thread
Reviewed by: Patrick Mooney <patrick.mooney@joyent.com>
Reviewed by: Yuri Pankov <yuripv@yuripv.net>

*** 8,18 ****
   * source.  A copy of the CDDL is also available via the Internet at
   * http://www.illumos.org/license/CDDL.
   */
  
  /*
!  * Copyright 2015 Joyent, Inc.
   */
  
  #if !defined(__lint)
          .file   "unix_sup.s"
  #endif /* __lint */
--- 8,18 ----
   * source.  A copy of the CDDL is also available via the Internet at
   * http://www.illumos.org/license/CDDL.
   */
  
  /*
!  * Copyright 2018 Joyent, Inc.
   */
  
  #if !defined(__lint)
          .file   "unix_sup.s"
  #endif /* __lint */
*** 30,39 ****
--- 30,43 ----
  ulong_t
  kmdb_unix_getcr0(void)
  { return (0); }
  
  ulong_t
+ kmdb_unix_getcr3(void)
+ { return (0); }
+ 
+ ulong_t
  kmdb_unix_getcr4(void)
  { return (0); }
  
  #else   /* __lint */
  
*** 41,50 ****
--- 45,64 ----
          ENTRY(kmdb_unix_getcr0)
          movq %cr0, %rax
          ret
          SET_SIZE(kmdb_unix_getcr0)
  
+         ENTRY(kmdb_unix_getcr2)
+         movq %cr2, %rax
+         ret
+         SET_SIZE(kmdb_unix_getcr2)
+ 
+         ENTRY(kmdb_unix_getcr3)
+         movq %cr3, %rax
+         ret
+         SET_SIZE(kmdb_unix_getcr3)
+ 
          ENTRY(kmdb_unix_getcr4)
          movq %cr4, %rax
          ret
          SET_SIZE(kmdb_unix_getcr4)
  
*** 52,61 ****
--- 66,85 ----
          ENTRY(kmdb_unix_getcr0)
          movl %cr0, %eax
          ret
          SET_SIZE(kmdb_unix_getcr0)
  
+         ENTRY(kmdb_unix_getcr2)
+         movl %cr2, %eax
+         ret
+         SET_SIZE(kmdb_unix_getcr2)
+ 
+         ENTRY(kmdb_unix_getcr3)
+         movl %cr3, %eax
+         ret
+         SET_SIZE(kmdb_unix_getcr3)
+ 
          ENTRY(kmdb_unix_getcr4)
          movl %cr4, %eax
          ret
          SET_SIZE(kmdb_unix_getcr4)