9600 LDT still not happy under KPTI

*** 2052,2076 ****
   * every context switch by installing different context ops, depending on
   * x86_featureset, at LDT creation time -- one for each combination of fast
   * syscall features.
   */
  
- /*ARGSUSED*/
  void
! cpu_fast_syscall_disable(void *arg)
  {
          if (is_x86_feature(x86_featureset, X86FSET_MSR) &&
              is_x86_feature(x86_featureset, X86FSET_SEP))
                  cpu_sep_disable();
          if (is_x86_feature(x86_featureset, X86FSET_MSR) &&
              is_x86_feature(x86_featureset, X86FSET_ASYSC))
                  cpu_asysc_disable();
  }
  
- /*ARGSUSED*/
  void
! cpu_fast_syscall_enable(void *arg)
  {
          if (is_x86_feature(x86_featureset, X86FSET_MSR) &&
              is_x86_feature(x86_featureset, X86FSET_SEP))
                  cpu_sep_enable();
          if (is_x86_feature(x86_featureset, X86FSET_MSR) &&
--- 2052,2074 ----
   * every context switch by installing different context ops, depending on
   * x86_featureset, at LDT creation time -- one for each combination of fast
   * syscall features.
   */
  
  void
! cpu_fast_syscall_disable(void)
  {
          if (is_x86_feature(x86_featureset, X86FSET_MSR) &&
              is_x86_feature(x86_featureset, X86FSET_SEP))
                  cpu_sep_disable();
          if (is_x86_feature(x86_featureset, X86FSET_MSR) &&
              is_x86_feature(x86_featureset, X86FSET_ASYSC))
                  cpu_asysc_disable();
  }
  
  void
! cpu_fast_syscall_enable(void)
  {
          if (is_x86_feature(x86_featureset, X86FSET_MSR) &&
              is_x86_feature(x86_featureset, X86FSET_SEP))
                  cpu_sep_enable();
          if (is_x86_feature(x86_featureset, X86FSET_MSR) &&