diff --git a/bochs/cpu/apic.cc b/bochs/cpu/apic.cc
index ff0a9734a..f50f996a7 100644
--- a/bochs/cpu/apic.cc
+++ b/bochs/cpu/apic.cc
@@ -1173,8 +1173,7 @@ void bx_local_apic_c::deactivate_vmx_preemption_timer(void)
 void bx_local_apic_c::vmx_preemption_timer_expired(void *this_ptr)
 {
   bx_local_apic_c *class_ptr = (bx_local_apic_c *) this_ptr;
-  class_ptr->cpu->pending_vmx_timer_expired = 1;
-  class_ptr->cpu->async_event = 1;
+  class_ptr->cpu->signal_event(BX_EVENT_VMX_PREEMPTION_TIMER_EXPIRED);
   class_ptr->deactivate_vmx_preemption_timer();
 }
 #endif
diff --git a/bochs/cpu/cpu.cc b/bochs/cpu/cpu.cc
index cee3015da..cbe5466ca 100644
--- a/bochs/cpu/cpu.cc
+++ b/bochs/cpu/cpu.cc
@@ -589,8 +589,7 @@ void BX_CPU_C::prefetch(void)
 
 #if BX_X86_DEBUGGER
   if (hwbreakpoint_check(laddr, BX_HWDebugInstruction, BX_HWDebugInstruction)) {
-    BX_CPU_THIS_PTR async_event = 1;
-    BX_CPU_THIS_PTR codebp = 1;
+    signal_event(BX_EVENT_CODE_BREAKPOINT_ASSIST);
     if (! interrupts_inhibited(BX_INHIBIT_DEBUG)) {
        // The next instruction could already hit a code breakpoint but
        // async_event won't take effect immediatelly.
@@ -609,7 +608,7 @@ void BX_CPU_C::prefetch(void)
     }
   }
   else {
-    BX_CPU_THIS_PTR codebp = 0;
+    clear_event(BX_EVENT_CODE_BREAKPOINT_ASSIST);
   }
 #endif
 
diff --git a/bochs/cpu/cpu.h b/bochs/cpu/cpu.h
index 09b51c889..32e450964 100644
--- a/bochs/cpu/cpu.h
+++ b/bochs/cpu/cpu.h
@@ -611,15 +611,15 @@ BOCHSAPI extern BX_CPU_C   bx_cpu;
   }
 
 // invalidate prefetch queue and call prefetch() when RF is set
-#define IMPLEMENT_EFLAG_SET_ACCESSOR_RF(name,bitnum)            \
-  BX_CPP_INLINE void BX_CPU_C::assert_##name() {                \
+#define IMPLEMENT_EFLAG_SET_ACCESSOR_RF(bitnum)                 \
+  BX_CPP_INLINE void BX_CPU_C::assert_RF() {                    \
     invalidate_prefetch_q();                                    \
     BX_CPU_THIS_PTR eflags |= (1<<bitnum);                      \
   }                                                             \
-  BX_CPP_INLINE void BX_CPU_C::clear_##name() {                 \
+  BX_CPP_INLINE void BX_CPU_C::clear_RF() {                     \
     BX_CPU_THIS_PTR eflags &= ~(1<<bitnum);                     \
   }                                                             \
-  BX_CPP_INLINE void BX_CPU_C::set_##name(bx_bool val) {        \
+  BX_CPP_INLINE void BX_CPU_C::set_RF(bx_bool val) {            \
     if (val) invalidate_prefetch_q();                           \
     BX_CPU_THIS_PTR eflags =                                    \
       (BX_CPU_THIS_PTR eflags&~(1<<bitnum))|((val)<<bitnum);    \
@@ -1049,10 +1049,6 @@ public: // for now...
   bx_bool in_vmx_guest;
   bx_bool in_smm_vmx; // save in_vmx and in_vmx_guest flags when in SMM mode
   bx_bool in_smm_vmx_guest;
-  bx_bool vmx_interrupt_window;
-#if BX_SUPPORT_VMX >= 2
-  bx_bool pending_vmx_timer_expired;
-#endif
   Bit64u  vmcsptr;
   bx_hostpageaddr_t vmcshostptr;
   Bit64u  vmxonptr;
@@ -1094,24 +1090,54 @@ public: // for now...
 #define BX_ACTIVITY_STATE_MWAIT_IF      (5)
   unsigned activity_state;
 
+#define BX_EVENT_NMI                          (1<<0)
+#define BX_EVENT_SMI                          (1<<1)
+#define BX_EVENT_INIT                         (1<<2)
+#define BX_EVENT_CODE_BREAKPOINT_ASSIST       (1<<3)
+#define BX_EVENT_VMX_PREEMPTION_TIMER_EXPIRED (1<<4)
+#define BX_EVENT_VMX_INTERRUPT_WINDOW_EXITING (1<<5)
+#define BX_EVENT_VMX_NMI_WINDOW_EXITING       (1<<6)
+// later the event list will grow rapidly
+  Bit32u  pending_event;
+  Bit32u  event_mask;
   Bit32u  async_event;
 
-#define BX_ASYNC_EVENT_STOP_TRACE (0x80000000)
+  BX_SMF BX_CPP_INLINE void signal_event(Bit32u event) {
+    BX_CPU_THIS_PTR pending_event |= event;
+    BX_CPU_THIS_PTR async_event = 1;
+  }
+
+  BX_SMF BX_CPP_INLINE void clear_event(Bit32u event) {
+    BX_CPU_THIS_PTR pending_event &= ~event;
+  }
+
+  BX_SMF BX_CPP_INLINE void mask_event(Bit32u event) {
+    BX_CPU_THIS_PTR event_mask |= event;
+  }
+  BX_SMF BX_CPP_INLINE void unmask_event(Bit32u event) {
+    BX_CPU_THIS_PTR event_mask &= ~event;
+  }
+
+  BX_SMF BX_CPP_INLINE bx_bool is_masked_event(Bit32u event) {
+    return (BX_CPU_THIS_PTR event_mask & event) != 0;
+  }
+
+  BX_SMF BX_CPP_INLINE bx_bool is_pending(Bit32u event) {
+    return (BX_CPU_THIS_PTR pending_event & event) != 0;
+  }
+  BX_SMF BX_CPP_INLINE bx_bool is_unmasked_event_pending(Bit32u event) {
+    return (BX_CPU_THIS_PTR pending_event & ~BX_CPU_THIS_PTR event_mask & event) != 0;
+  }
+
+#define BX_ASYNC_EVENT_STOP_TRACE (1<<31)
 
 #if BX_X86_DEBUGGER
   bx_bool  in_repeat;
-  bx_bool  codebp;
 #endif
   bx_bool  in_smm;
   unsigned cpu_mode;
   bx_bool  user_pl;
   bx_bool  INTR;
-  bx_bool  pending_SMI;
-  bx_bool  pending_NMI;
-  bx_bool  pending_INIT;
-  bx_bool  disable_SMI;
-  bx_bool  disable_NMI;
-  bx_bool  disable_INIT;
 #if BX_CPU_LEVEL >= 5
   bx_bool  ignore_bad_msrs;
 #endif
@@ -4756,7 +4782,7 @@ IMPLEMENT_EFLAG_SET_ACCESSOR_AC   (     18)
 IMPLEMENT_EFLAG_SET_ACCESSOR      (AC,  18)
 #endif
 IMPLEMENT_EFLAG_SET_ACCESSOR_VM   (     17)
-IMPLEMENT_EFLAG_SET_ACCESSOR_RF   (RF,  16)
+IMPLEMENT_EFLAG_SET_ACCESSOR_RF   (     16)
 IMPLEMENT_EFLAG_SET_ACCESSOR      (NT,  14)
 IMPLEMENT_EFLAG_SET_ACCESSOR      (DF,  10)
 IMPLEMENT_EFLAG_SET_ACCESSOR_IF_TF(IF,   9)
diff --git a/bochs/cpu/ctrl_xfer16.cc b/bochs/cpu/ctrl_xfer16.cc
index 688b744df..6f7dabaef 100644
--- a/bochs/cpu/ctrl_xfer16.cc
+++ b/bochs/cpu/ctrl_xfer16.cc
@@ -547,7 +547,7 @@ BX_INSF_TYPE BX_CPP_AttrRegparmN(1) BX_CPU_C::IRET16(bxInstruction_c *i)
 #if BX_SUPPORT_VMX
   if (!BX_CPU_THIS_PTR in_vmx_guest || !VMEXIT(VMX_VM_EXEC_CTRL1_NMI_VMEXIT))
 #endif
-    BX_CPU_THIS_PTR disable_NMI = 0;
+    unmask_event(BX_EVENT_NMI);
 
 #if BX_DEBUGGER
   BX_CPU_THIS_PTR show_flag |= Flag_iret;
diff --git a/bochs/cpu/ctrl_xfer32.cc b/bochs/cpu/ctrl_xfer32.cc
index df31e4593..a37cf47ce 100644
--- a/bochs/cpu/ctrl_xfer32.cc
+++ b/bochs/cpu/ctrl_xfer32.cc
@@ -590,7 +590,7 @@ BX_INSF_TYPE BX_CPP_AttrRegparmN(1) BX_CPU_C::IRET32(bxInstruction_c *i)
 #if BX_SUPPORT_VMX
   if (!BX_CPU_THIS_PTR in_vmx_guest || !VMEXIT(VMX_VM_EXEC_CTRL1_NMI_VMEXIT))
 #endif
-    BX_CPU_THIS_PTR disable_NMI = 0;
+    unmask_event(BX_EVENT_NMI);
 
 #if BX_DEBUGGER
   BX_CPU_THIS_PTR show_flag |= Flag_iret;
diff --git a/bochs/cpu/ctrl_xfer64.cc b/bochs/cpu/ctrl_xfer64.cc
index 40f05653e..d65ab1cef 100644
--- a/bochs/cpu/ctrl_xfer64.cc
+++ b/bochs/cpu/ctrl_xfer64.cc
@@ -429,7 +429,7 @@ BX_INSF_TYPE BX_CPP_AttrRegparmN(1) BX_CPU_C::IRET64(bxInstruction_c *i)
 #if BX_SUPPORT_VMX
   if (!BX_CPU_THIS_PTR in_vmx_guest || !VMEXIT(VMX_VM_EXEC_CTRL1_NMI_VMEXIT))
 #endif
-    BX_CPU_THIS_PTR disable_NMI = 0;
+    unmask_event(BX_EVENT_NMI);
 
 #if BX_DEBUGGER
   BX_CPU_THIS_PTR show_flag |= Flag_iret;
diff --git a/bochs/cpu/event.cc b/bochs/cpu/event.cc
index c039a6579..0120ec81b 100644
--- a/bochs/cpu/event.cc
+++ b/bochs/cpu/event.cc
@@ -34,10 +34,7 @@ bx_bool BX_CPU_C::handleWaitForEvent(void)
   while (1)
   {
     if ((BX_CPU_INTR && (BX_CPU_THIS_PTR get_IF() || BX_CPU_THIS_PTR activity_state == BX_ACTIVITY_STATE_MWAIT_IF)) ||
-#if BX_SUPPORT_VMX >= 2
-         BX_CPU_THIS_PTR pending_vmx_timer_expired ||
-#endif
-         BX_CPU_THIS_PTR pending_NMI || BX_CPU_THIS_PTR pending_SMI || BX_CPU_THIS_PTR pending_INIT)
+         is_pending(BX_EVENT_NMI | BX_EVENT_SMI | BX_EVENT_INIT | BX_EVENT_VMX_PREEMPTION_TIMER_EXPIRED))
     {
       // interrupt ends the HALT condition
 #if BX_SUPPORT_MONITOR_MWAIT
@@ -194,14 +191,14 @@ bx_bool BX_CPU_C::handleAsyncEvent(void)
   //   STOPCLK
   //   SMI
   //   INIT
-  if (BX_CPU_THIS_PTR pending_SMI && ! BX_CPU_THIS_PTR smm_mode() && SVM_GIF)
+  if (is_pending(BX_EVENT_SMI) && ! BX_CPU_THIS_PTR smm_mode() && SVM_GIF)
   {
     // clear SMI pending flag and disable NMI when SMM was accepted
-    BX_CPU_THIS_PTR pending_SMI = 0;
+    clear_event(BX_EVENT_SMI);
     enter_system_management_mode();
   }
 
-  if (BX_CPU_THIS_PTR pending_INIT && ! BX_CPU_THIS_PTR disable_INIT && SVM_GIF) {
+  if (is_unmasked_event_pending(BX_EVENT_INIT) && SVM_GIF) {
 #if BX_SUPPORT_SVM
     if (BX_CPU_THIS_PTR in_svm_guest) {
       if (SVM_INTERCEPT(SVM_INTERCEPT0_INIT)) Svm_Vmexit(SVM_VMEXIT_INIT);
@@ -255,13 +252,13 @@ bx_bool BX_CPU_C::handleAsyncEvent(void)
     // boundary because of certain instructions like STI.
   }
 #if BX_SUPPORT_VMX >= 2
-  else if (BX_CPU_THIS_PTR in_vmx_guest && BX_CPU_THIS_PTR pending_vmx_timer_expired) {
-    BX_CPU_THIS_PTR pending_vmx_timer_expired = 0;
+  else if (BX_CPU_THIS_PTR in_vmx_guest && is_pending(BX_EVENT_VMX_PREEMPTION_TIMER_EXPIRED)) {
+    clear_event(BX_EVENT_VMX_PREEMPTION_TIMER_EXPIRED);
     VMexit_PreemptionTimerExpired();
   }
 #endif
 #if BX_SUPPORT_VMX
-  else if (! BX_CPU_THIS_PTR disable_NMI && BX_CPU_THIS_PTR in_vmx_guest && 
+  else if (! is_masked_event(BX_EVENT_NMI) && BX_CPU_THIS_PTR in_vmx_guest && 
        VMEXIT(VMX_VM_EXEC_CTRL2_NMI_WINDOW_VMEXIT))
   {
     // NMI-window exiting
@@ -269,14 +266,14 @@ bx_bool BX_CPU_C::handleAsyncEvent(void)
     VMexit(VMX_VMEXIT_NMI_WINDOW, 0);
   }
 #endif
-  else if (BX_CPU_THIS_PTR pending_NMI && ! BX_CPU_THIS_PTR disable_NMI) {
+  else if (is_unmasked_event_pending(BX_EVENT_NMI)) {
 #if BX_SUPPORT_SVM
     if (BX_CPU_THIS_PTR in_svm_guest) {
       if (SVM_INTERCEPT(SVM_INTERCEPT0_NMI)) Svm_Vmexit(SVM_VMEXIT_NMI);
     }
 #endif
-    BX_CPU_THIS_PTR pending_NMI = 0;
-    BX_CPU_THIS_PTR disable_NMI = 1;
+    clear_event(BX_EVENT_NMI);
+     mask_event(BX_EVENT_NMI);
     BX_CPU_THIS_PTR EXT = 1; /* external event */
 #if BX_SUPPORT_VMX
     VMexit_Event(BX_NMI, 2, 0, 0);
@@ -285,7 +282,7 @@ bx_bool BX_CPU_C::handleAsyncEvent(void)
     interrupt(2, BX_NMI, 0, 0);
   }
 #if BX_SUPPORT_VMX
-  else if (BX_CPU_THIS_PTR vmx_interrupt_window && BX_CPU_THIS_PTR get_IF()) {
+  else if (is_pending(BX_EVENT_VMX_INTERRUPT_WINDOW_EXITING) && BX_CPU_THIS_PTR get_IF()) {
     // interrupt-window exiting
     BX_DEBUG(("VMEXIT: interrupt window exiting"));
     VMexit(VMX_VMEXIT_INTERRUPT_WINDOW, 0);
@@ -351,12 +348,12 @@ bx_bool BX_CPU_C::handleAsyncEvent(void)
 //      BX_CPU_THIS_PTR get_TF() // implies debug_trap is set
         BX_HRQ
 #if BX_SUPPORT_VMX
-     || BX_CPU_THIS_PTR vmx_interrupt_window
-     || (BX_CPU_THIS_PTR in_vmx_guest && ! BX_CPU_THIS_PTR disable_NMI &&
+     || is_pending(BX_EVENT_VMX_INTERRUPT_WINDOW_EXITING)
+     || (BX_CPU_THIS_PTR in_vmx_guest && ! is_masked_event(BX_EVENT_NMI) &&
        VMEXIT(VMX_VM_EXEC_CTRL2_NMI_WINDOW_VMEXIT))
 #endif
 #if BX_SUPPORT_VMX >= 2
-     || BX_CPU_THIS_PTR pending_vmx_timer_expired
+     || is_pending(BX_EVENT_VMX_PREEMPTION_TIMER_EXPIRED)
 #endif
 #if BX_SUPPORT_SVM
     || (BX_CPU_THIS_PTR in_svm_guest && SVM_V_IRQ && BX_CPU_THIS_PTR get_IF() &&
@@ -364,7 +361,7 @@ bx_bool BX_CPU_C::handleAsyncEvent(void)
 #endif
 #if BX_X86_DEBUGGER
      // a debug code breakpoint is set in current page
-     || BX_CPU_THIS_PTR codebp
+     || is_pending(BX_EVENT_CODE_BREAKPOINT_ASSIST)
 #endif
         ))
     BX_CPU_THIS_PTR async_event = 0;
@@ -391,7 +388,7 @@ void BX_CPU_C::deliver_SIPI(unsigned vector)
     BX_CPU_THIS_PTR activity_state = BX_ACTIVITY_STATE_ACTIVE;
     RIP = 0;
     load_seg_reg(&BX_CPU_THIS_PTR sregs[BX_SEG_REG_CS], vector*0x100);
-    BX_CPU_THIS_PTR disable_INIT = 0; // enable INIT pin back
+    unmask_event(BX_EVENT_INIT); // enable INIT pin back
     BX_INFO(("CPU %d started up at %04X:%08X by APIC",
                    BX_CPU_THIS_PTR bx_cpuid, vector*0x100, EIP));
   } else {
@@ -401,22 +398,19 @@ void BX_CPU_C::deliver_SIPI(unsigned vector)
 
 void BX_CPU_C::deliver_INIT(void)
 {
-  if (! BX_CPU_THIS_PTR disable_INIT) {
-    BX_CPU_THIS_PTR pending_INIT = 1;
-    BX_CPU_THIS_PTR async_event = 1;
+  if (! is_masked_event(BX_EVENT_INIT)) {
+    signal_event(BX_EVENT_INIT);
   }
 }
 
 void BX_CPU_C::deliver_NMI(void)
 {
-  BX_CPU_THIS_PTR pending_NMI = 1;
-  BX_CPU_THIS_PTR async_event = 1;
+  signal_event(BX_EVENT_NMI);
 }
 
 void BX_CPU_C::deliver_SMI(void)
 {
-  BX_CPU_THIS_PTR pending_SMI = 1;
-  BX_CPU_THIS_PTR async_event = 1;
+  signal_event(BX_EVENT_SMI);
 }
 
 void BX_CPU_C::set_INTR(bx_bool value)
diff --git a/bochs/cpu/flag_ctrl_pro.cc b/bochs/cpu/flag_ctrl_pro.cc
index 6927efbc7..f74af1fc7 100644
--- a/bochs/cpu/flag_ctrl_pro.cc
+++ b/bochs/cpu/flag_ctrl_pro.cc
@@ -38,7 +38,7 @@ void BX_CPP_AttrRegparmN(1) BX_CPU_C::setEFlags(Bit32u val)
   if (val & EFlagsRFMask) invalidate_prefetch_q();
 
   if (val & EFlagsTFMask) {
-    BX_CPU_THIS_PTR async_event = 1; // TF == 1 || RF == 1
+    BX_CPU_THIS_PTR async_event = 1; // TF == 1
   }
 
   if (val & EFlagsIFMask) {
diff --git a/bochs/cpu/init.cc b/bochs/cpu/init.cc
index 605d21d47..49d8dac40 100644
--- a/bochs/cpu/init.cc
+++ b/bochs/cpu/init.cc
@@ -624,22 +624,16 @@ void BX_CPU_C::register_state(void)
   register_svm_state(cpu);
 #endif
 
+  BXRS_HEX_PARAM_SIMPLE32(cpu, pending_event);
+  BXRS_HEX_PARAM_SIMPLE32(cpu, event_mask);
   BXRS_HEX_PARAM_SIMPLE32(cpu, async_event);
   BXRS_PARAM_BOOL(cpu, INTR, INTR);
 
 #if BX_X86_DEBUGGER
   BXRS_PARAM_BOOL(cpu, in_repeat, in_repeat);
-  // for debug only (no need for save/restore), calculated in prefetch()
-  BXRS_PARAM_BOOL(cpu, codebp, codebp);
 #endif
 
   BXRS_PARAM_BOOL(cpu, in_smm, in_smm);
-  BXRS_PARAM_BOOL(cpu, disable_SMI, disable_SMI);
-  BXRS_PARAM_BOOL(cpu, pending_SMI, pending_SMI);
-  BXRS_PARAM_BOOL(cpu, disable_NMI, disable_NMI);
-  BXRS_PARAM_BOOL(cpu, pending_NMI, pending_NMI);
-  BXRS_PARAM_BOOL(cpu, disable_INIT, disable_INIT);
-  BXRS_PARAM_BOOL(cpu, pending_INIT, pending_INIT);
 
 #if BX_DEBUGGER
   bx_list_c *tlb = new bx_list_c(cpu, "TLB");
@@ -942,15 +936,11 @@ void BX_CPU_C::reset(unsigned source)
 
 #if BX_X86_DEBUGGER
   BX_CPU_THIS_PTR in_repeat = 0;
-  BX_CPU_THIS_PTR codebp = 0;
 #endif
   BX_CPU_THIS_PTR in_smm = 0;
-  BX_CPU_THIS_PTR disable_SMI = 0;
-  BX_CPU_THIS_PTR pending_SMI = 0;
-  BX_CPU_THIS_PTR disable_NMI = 0;
-  BX_CPU_THIS_PTR pending_NMI = 0;
-  BX_CPU_THIS_PTR disable_INIT = 0;
-  BX_CPU_THIS_PTR pending_INIT = 0;
+
+  BX_CPU_THIS_PTR pending_event = 0;
+  BX_CPU_THIS_PTR event_mask = 0;
 
   if (source == BX_RESET_HARDWARE) {
     BX_CPU_THIS_PTR smbase = 0x30000; // do not change SMBASE on INIT
@@ -1121,10 +1111,6 @@ void BX_CPU_C::reset(unsigned source)
 #if BX_SUPPORT_VMX
   BX_CPU_THIS_PTR in_vmx = BX_CPU_THIS_PTR in_vmx_guest = 0;
   BX_CPU_THIS_PTR in_smm_vmx = BX_CPU_THIS_PTR in_smm_vmx_guest = 0;
-  BX_CPU_THIS_PTR vmx_interrupt_window = 0;
-#if BX_SUPPORT_VMX >= 2  
-  BX_CPU_THIS_PTR pending_vmx_timer_expired = 0;
-#endif
   BX_CPU_THIS_PTR vmcsptr = BX_CPU_THIS_PTR vmxonptr = BX_INVALID_VMCSPTR;
   BX_CPU_THIS_PTR vmcshostptr = 0;
   /* enable VMX, should be done in BIOS instead */
diff --git a/bochs/cpu/proc_ctrl.cc b/bochs/cpu/proc_ctrl.cc
index 8008df23a..d1708ee88 100644
--- a/bochs/cpu/proc_ctrl.cc
+++ b/bochs/cpu/proc_ctrl.cc
@@ -777,10 +777,11 @@ BX_INSF_TYPE BX_CPP_AttrRegparmN(1) BX_CPU_C::MWAIT(bxInstruction_c *i)
   if (ECX & 1) {
 #if BX_SUPPORT_VMX
     // When "interrupt window exiting" VMX control is set MWAIT instruction
-    // won't cause the processor to enter BX_ACTIVITY_STATE_MWAIT_IF sleep
-    // state with EFLAGS.IF = 0
-    if (BX_CPU_THIS_PTR vmx_interrupt_window && ! BX_CPU_THIS_PTR get_IF()) {
-      BX_NEXT_TRACE(i);
+    // won't cause the processor to enter sleep state with EFLAGS.IF = 0
+    if (BX_CPU_THIS_PTR in_vmx_guest) {
+      if (VMEXIT(VMX_VM_EXEC_CTRL2_INTERRUPT_WINDOW_VMEXIT) && ! BX_CPU_THIS_PTR get_IF()) {
+        BX_NEXT_TRACE(i);
+      }
     }
 #endif
     BX_CPU_THIS_PTR activity_state = BX_ACTIVITY_STATE_MWAIT_IF;
diff --git a/bochs/cpu/smm.cc b/bochs/cpu/smm.cc
index 5681df58a..35dd2a9e3 100644
--- a/bochs/cpu/smm.cc
+++ b/bochs/cpu/smm.cc
@@ -51,7 +51,7 @@ BX_INSF_TYPE BX_CPP_AttrRegparmN(1) BX_CPU_C::RSM(bxInstruction_c *i)
 
   BX_INFO(("RSM: Resuming from System Management Mode"));
 
-  BX_CPU_THIS_PTR disable_NMI = 0;
+  unmask_event(BX_EVENT_NMI | BX_EVENT_SMI);
 
   Bit32u saved_state[SMM_SAVE_STATE_MAP_SIZE], n;
   // reset reserved bits
@@ -114,7 +114,8 @@ void BX_CPU_C::enter_system_management_mode(void)
 #endif
 
   BX_CPU_THIS_PTR in_smm = 1;
-  BX_CPU_THIS_PTR disable_NMI = 1;
+
+  mask_event(BX_EVENT_NMI | BX_EVENT_SMI);
 
   Bit32u saved_state[SMM_SAVE_STATE_MAP_SIZE], n;
   // reset reserved bits
diff --git a/bochs/cpu/vmx.cc b/bochs/cpu/vmx.cc
index 7d8cd517b..0be3c9e66 100644
--- a/bochs/cpu/vmx.cc
+++ b/bochs/cpu/vmx.cc
@@ -1635,7 +1635,7 @@ Bit32u BX_CPU_C::VMenterLoadCheckGuestState(Bit64u *qualification)
   }
 
   if (guest.interruptibility_state & BX_VMX_INTERRUPTS_BLOCKED_NMI_BLOCKED) {
-    BX_CPU_THIS_PTR disable_NMI = 1;
+    mask_event(BX_EVENT_NMI);
   }
   else {
     if (vm->vmexec_ctrls2 & VMX_VM_EXEC_CTRL2_NMI_WINDOW_VMEXIT)
@@ -1643,8 +1643,7 @@ Bit32u BX_CPU_C::VMenterLoadCheckGuestState(Bit64u *qualification)
   }
 
   if (vm->vmexec_ctrls2 & VMX_VM_EXEC_CTRL2_INTERRUPT_WINDOW_VMEXIT) {
-    BX_CPU_THIS_PTR async_event = 1;
-    BX_CPU_THIS_PTR vmx_interrupt_window = 1; // set up interrupt window exiting
+    signal_event(BX_EVENT_VMX_INTERRUPT_WINDOW_EXITING);
   }
 
   handleCpuContextChange();
@@ -1876,9 +1875,9 @@ void BX_CPU_C::VMexitSaveGuestState(void)
      else
         interruptibility_state |= BX_VMX_INTERRUPTS_BLOCKED_BY_STI;
   }
-  if (BX_CPU_THIS_PTR disable_SMI)
+  if (is_masked_event(BX_EVENT_SMI))
     interruptibility_state |= BX_VMX_INTERRUPTS_BLOCKED_SMI_BLOCKED;
-  if (BX_CPU_THIS_PTR disable_NMI)
+  if (is_masked_event(BX_EVENT_NMI))
     interruptibility_state |= BX_VMX_INTERRUPTS_BLOCKED_NMI_BLOCKED;
   VMwrite32(VMCS_32BIT_GUEST_INTERRUPTIBILITY_STATE, interruptibility_state);
 
@@ -1896,7 +1895,7 @@ void BX_CPU_C::VMexitSaveGuestState(void)
 
   // Deactivate VMX preemtion timer
   BX_CPU_THIS_PTR lapic.deactivate_vmx_preemption_timer();
-  BX_CPU_THIS_PTR pending_vmx_timer_expired = 0;
+  clear_event(BX_EVENT_VMX_PREEMPTION_TIMER_EXPIRED);
   // Store back to VMCS
   if (vm->vmexit_ctrls & VMX_VMEXIT_CTRL1_STORE_VMX_PREEMPTION_TIMER)
     VMwrite32(VMCS_32BIT_GUEST_PREEMPTION_TIMER_VALUE, BX_CPU_THIS_PTR lapic.read_vmx_preemption_timer());
@@ -2142,6 +2141,11 @@ void BX_CPU_C::VMexit(Bit32u reason, Bit64u qualification)
 
   BX_CPU_THIS_PTR in_vmx_guest = 0;
 
+  // entering VMX root mode: clear possibly pending guest VMX events
+  clear_event(BX_EVENT_VMX_INTERRUPT_WINDOW_EXITING |
+              BX_EVENT_VMX_PREEMPTION_TIMER_EXPIRED |
+              BX_EVENT_VMX_NMI_WINDOW_EXITING);
+
   //
   // STEP 2: Load Host State
   //
@@ -2161,8 +2165,8 @@ void BX_CPU_C::VMexit(Bit32u reason, Bit64u qualification)
   // STEP 4: Go back to VMX host
   //
 
-  BX_CPU_THIS_PTR disable_INIT = 1; // INIT is disabled in VMX root mode
-  BX_CPU_THIS_PTR vmx_interrupt_window = 0;
+  mask_event(BX_EVENT_INIT); // INIT is disabled in VMX root mode
+
   BX_CPU_THIS_PTR errorno = 0;
   BX_CPU_THIS_PTR EXT = 0;
 
@@ -2217,7 +2221,7 @@ BX_INSF_TYPE BX_CPP_AttrRegparmN(1) BX_CPU_C::VMXON(bxInstruction_c *i)
     BX_CPU_THIS_PTR vmcshostptr = 0;
     BX_CPU_THIS_PTR vmxonptr = pAddr;
     BX_CPU_THIS_PTR in_vmx = 1;
-    BX_CPU_THIS_PTR disable_INIT = 1; // INIT is disabled in VMX root mode
+    mask_event(BX_EVENT_INIT); // INIT is disabled in VMX root mode
     // block and disable A20M;
 
 #if BX_SUPPORT_MONITOR_MWAIT
@@ -2268,7 +2272,7 @@ BX_INSF_TYPE BX_CPP_AttrRegparmN(1) BX_CPU_C::VMXOFF(bxInstruction_c *i)
   {
     BX_CPU_THIS_PTR vmxonptr = BX_INVALID_VMCSPTR;
     BX_CPU_THIS_PTR in_vmx = 0;  // leave VMX operation mode
-    BX_CPU_THIS_PTR disable_INIT = 0;
+    unmask_event(BX_EVENT_INIT);
      // unblock and enable A20M;
 #if BX_SUPPORT_MONITOR_MWAIT
     BX_CPU_THIS_PTR monitor.reset_monitor();
@@ -2504,7 +2508,8 @@ BX_INSF_TYPE BX_CPP_AttrRegparmN(1) BX_CPU_C::VMLAUNCH(bxInstruction_c *i)
 */
 
   BX_CPU_THIS_PTR in_vmx_guest = 1;
-  BX_CPU_THIS_PTR disable_INIT = 0;
+
+  unmask_event(BX_EVENT_INIT);
 
   if (VMEXIT(VMX_VM_EXEC_CTRL2_TSC_OFFSET))
     BX_CPU_THIS_PTR tsc_offset = VMread64(VMCS_64BIT_CONTROL_TSC_OFFSET);
@@ -2515,13 +2520,11 @@ BX_INSF_TYPE BX_CPP_AttrRegparmN(1) BX_CPU_C::VMLAUNCH(bxInstruction_c *i)
   if (PIN_VMEXIT(VMX_VM_EXEC_CTRL1_VMX_PREEMPTION_TIMER_VMEXIT)) {
     Bit32u timer_value = VMread32(VMCS_32BIT_GUEST_PREEMPTION_TIMER_VALUE);
     if (timer_value == 0) {
-      BX_CPU_THIS_PTR pending_vmx_timer_expired = 1;
-      BX_CPU_THIS_PTR async_event = 1;
+      signal_event(BX_EVENT_VMX_PREEMPTION_TIMER_EXPIRED);
     }
     else {
       // activate VMX preemption timer
       BX_DEBUG(("VMX preemption timer active"));
-      BX_CPU_THIS_PTR pending_vmx_timer_expired = 0;
       BX_CPU_THIS_PTR lapic.set_vmx_preemption_timer(timer_value);
     }
   }
@@ -3127,10 +3130,6 @@ void BX_CPU_C::register_vmx_state(bx_param_c *parent)
   BXRS_PARAM_BOOL(vmx, in_vmx_guest, BX_CPU_THIS_PTR in_vmx_guest);
   BXRS_PARAM_BOOL(vmx, in_smm_vmx, BX_CPU_THIS_PTR in_smm_vmx);
   BXRS_PARAM_BOOL(vmx, in_smm_vmx_guest, BX_CPU_THIS_PTR in_smm_vmx_guest);
-  BXRS_PARAM_BOOL(vmx, vmx_interrupt_window, BX_CPU_THIS_PTR vmx_interrupt_window);
-#if BX_SUPPORT_VMX >= 2
-  BXRS_PARAM_BOOL(vmx, pending_vmx_timer_expired, BX_CPU_THIS_PTR pending_vmx_timer_expired);
-#endif
 
   bx_list_c *vmcache = new bx_list_c(vmx, "VMCS_CACHE");