OS-7125 Need mitigation of L1TF (CVE-2018-3646)
Reviewed by: Robert Mustacchi <rm@joyent.com>
Reviewed by: Jerry Jelinek <jerry.jelinek@joyent.com>

*** 464,492 ****
  #include <sys/archsystm.h>
  #include <sys/machsystm.h>
  #include <sys/ontrap.h>
  #include <sys/x86_archext.h>
  #include <sys/promif.h>
  #include <vm/hat_i86.h>
  #if defined(__xpv)
  #include <sys/hypervisor.h>
  #endif
  
! #if defined(__amd64) && !defined(__xpv)
! /* If this fails, then the padding numbers in machcpuvar.h are wrong. */
! CTASSERT((offsetof(cpu_t, cpu_m) + offsetof(struct machcpu, mcpu_pad)) <
!     MMU_PAGESIZE);
! CTASSERT((offsetof(cpu_t, cpu_m) + offsetof(struct machcpu, mcpu_kpti)) >=
!     MMU_PAGESIZE);
! CTASSERT((offsetof(cpu_t, cpu_m) + offsetof(struct machcpu, mcpu_kpti_dbg)) <
!     2 * MMU_PAGESIZE);
! CTASSERT((offsetof(cpu_t, cpu_m) + offsetof(struct machcpu, mcpu_pad2)) <
!     2 * MMU_PAGESIZE);
  CTASSERT(((sizeof (struct kpti_frame)) & 0xF) == 0);
- CTASSERT(((offsetof(cpu_t, cpu_m) +
-     offsetof(struct machcpu, mcpu_kpti_dbg)) & 0xF) == 0);
  CTASSERT((offsetof(struct kpti_frame, kf_tr_rsp) & 0xF) == 0);
  #endif
  
  #if defined(__xpv) && defined(DEBUG)
  
  /*
--- 464,489 ----
  #include <sys/archsystm.h>
  #include <sys/machsystm.h>
  #include <sys/ontrap.h>
  #include <sys/x86_archext.h>
  #include <sys/promif.h>
+ #include <sys/ht.h>
  #include <vm/hat_i86.h>
  #if defined(__xpv)
  #include <sys/hypervisor.h>
  #endif
  
! /* If these fail, then the padding numbers in machcpuvar.h are wrong. */
! #if !defined(__xpv)
! #define MCOFF(member)   \
!         (offsetof(cpu_t, cpu_m) + offsetof(struct machcpu, member))
! CTASSERT(MCOFF(mcpu_pad) == MACHCPU_SIZE);
! CTASSERT(MCOFF(mcpu_pad2) == MMU_PAGESIZE);
! CTASSERT((MCOFF(mcpu_kpti) & 0xF) == 0);
  CTASSERT(((sizeof (struct kpti_frame)) & 0xF) == 0);
  CTASSERT((offsetof(struct kpti_frame, kf_tr_rsp) & 0xF) == 0);
+ CTASSERT(MCOFF(mcpu_pad3) < 2 * MMU_PAGESIZE);
  #endif
  
  #if defined(__xpv) && defined(DEBUG)
  
  /*
*** 598,607 ****
--- 595,606 ----
                          cpu->cpu_intracct[cpu->cpu_mstate] += intrtime;
                          t->t_intr_start = 0;
                  }
          }
  
+         ht_begin_intr(pil);
+ 
          /*
           * Store starting timestamp in CPU structure for this PIL.
           */
          mcpu->pil_high_start[pil - (LOCK_LEVEL + 1)] = now;
  
*** 702,711 ****
--- 701,712 ----
  
                  if (t->t_flag & T_INTR_THREAD)
                          t->t_intr_start = now;
          }
  
+         ht_end_intr();
+ 
          mcpu->mcpu_pri = oldpil;
          (void) (*setlvlx)(oldpil, vecnum);
  
          return (cpu->cpu_intr_actv & CPU_INTR_ACTV_HIGH_LEVEL_MASK);
  }
*** 764,773 ****
--- 765,776 ----
           * they're TS_FREE.)
           */
          it->t_state = TS_ONPROC;
  
          cpu->cpu_thread = it;           /* new curthread on this cpu */
+         ht_begin_intr(pil);
+ 
          it->t_pil = (uchar_t)pil;
          it->t_pri = intr_pri + (pri_t)pil;
          it->t_intr_start = now;
  
          return (it->t_stk);
*** 854,863 ****
--- 857,867 ----
          basespl = cpu->cpu_base_spl;
          pil = MAX(oldpil, basespl);
          mcpu->mcpu_pri = pil;
          (*setlvlx)(pil, vec);
          t->t_intr_start = now;
+         ht_end_intr();
          cpu->cpu_thread = t;
  }
  
  /*
   * intr_get_time() is a resource for interrupt handlers to determine how
*** 1041,1050 ****
--- 1045,1055 ----
          ASSERT(SA((uintptr_t)stackptr) == (uintptr_t)stackptr);
          t->t_sp = (uintptr_t)stackptr;
  
          it->t_intr = t;
          cpu->cpu_thread = it;
+         ht_begin_intr(pil);
  
          /*
           * Set bit for this pil in CPU's interrupt active bitmask.
           */
          ASSERT((cpu->cpu_intr_actv & (1 << pil)) == 0);
*** 1101,1111 ****
--- 1106,1118 ----
                  panic("dosoftint_epilog: swtch returned");
          }
          it->t_link = cpu->cpu_intr_thread;
          cpu->cpu_intr_thread = it;
          it->t_state = TS_FREE;
+         ht_end_intr();
          cpu->cpu_thread = t;
+ 
          if (t->t_flag & T_INTR_THREAD)
                  t->t_intr_start = now;
          basespl = cpu->cpu_base_spl;
          pil = MAX(oldpil, basespl);
          mcpu->mcpu_pri = pil;