11787 Kernel needs to be built with retpolines
11788 Kernel needs to generally use RSB stuffing
Reviewed by: Jerry Jelinek <jerry.jelinek@joyent.com>
Reviewed by: John Levon <john.levon@joyent.com>

*** 586,596 ****
          testl   %eax, %eax                      /* check for non-zero probe */
          jz      1f
          pushq   %rbp                            /* align stack properly */
          movq    %rsp, %rbp
          movl    %eax, %edi
!         call    *lockstat_probe
          leave                                   /* unwind stack */
  1:
          movq    %gs:CPU_THREAD, %rdx            /* reload thread ptr */
          decb    T_LOCKSTAT(%rdx)                /* curthread->t_lockstat-- */
          movl    $1, %eax                        /* return success if tryenter */
--- 586,597 ----
          testl   %eax, %eax                      /* check for non-zero probe */
          jz      1f
          pushq   %rbp                            /* align stack properly */
          movq    %rsp, %rbp
          movl    %eax, %edi
!         movq    lockstat_probe, %rax
!         INDIRECT_CALL_REG(rax)
          leave                                   /* unwind stack */
  1:
          movq    %gs:CPU_THREAD, %rdx            /* reload thread ptr */
          decb    T_LOCKSTAT(%rdx)                /* curthread->t_lockstat-- */
          movl    $1, %eax                        /* return success if tryenter */
*** 608,618 ****
          testl   %eax, %eax                      /* check for non-zero probe */
          jz      1f
          pushq   %rbp                            /* align stack properly */
          movq    %rsp, %rbp
          movl    %eax, %edi
!         call    *lockstat_probe
          leave                                   /* unwind stack */
  1:
          movq    %gs:CPU_THREAD, %rdx            /* reload thread ptr */
          decb    T_LOCKSTAT(%rdx)                /* curthread->t_lockstat-- */
          movl    $1, %eax                        /* return success if tryenter */
--- 609,620 ----
          testl   %eax, %eax                      /* check for non-zero probe */
          jz      1f
          pushq   %rbp                            /* align stack properly */
          movq    %rsp, %rbp
          movl    %eax, %edi
!         movq    lockstat_probe, %rax
!         INDIRECT_CALL_REG(rax)
          leave                                   /* unwind stack */
  1:
          movq    %gs:CPU_THREAD, %rdx            /* reload thread ptr */
          decb    T_LOCKSTAT(%rdx)                /* curthread->t_lockstat-- */
          movl    $1, %eax                        /* return success if tryenter */