diff --git a/hypervisor/arch/x86/guest/instr_emul.c b/hypervisor/arch/x86/guest/instr_emul.c
index 3f9b259c6..f24528f46 100644
--- a/hypervisor/arch/x86/guest/instr_emul.c
+++ b/hypervisor/arch/x86/guest/instr_emul.c
@@ -1665,9 +1665,9 @@ vie_calculate_gla(enum vm_cpu_mode cpu_mode, enum vm_reg_name seg,
 }
 
 void
-vie_init(struct vie *vie, const char *inst_bytes, int inst_length)
+vie_init(struct vie *vie, const char *inst_bytes, uint32_t inst_length)
 {
-	ASSERT(inst_length >= 0 && inst_length <= VIE_INST_SIZE,
+	ASSERT(inst_length <= VIE_INST_SIZE,
 		"%s: invalid instruction length (%d)", __func__, inst_length);
 
 	memset(vie, 0, sizeof(struct vie));
diff --git a/hypervisor/arch/x86/guest/instr_emul.h b/hypervisor/arch/x86/guest/instr_emul.h
index f92015d7c..c3186e56c 100644
--- a/hypervisor/arch/x86/guest/instr_emul.h
+++ b/hypervisor/arch/x86/guest/instr_emul.h
@@ -72,7 +72,7 @@ int vie_calculate_gla(enum vm_cpu_mode cpu_mode, enum vm_reg_name seg,
 	struct seg_desc *desc, uint64_t off, int length, int addrsize, int prot,
 	uint64_t *gla);
 
-void vie_init(struct vie *vie, const char *inst_bytes, int inst_length);
+void vie_init(struct vie *vie, const char *inst_bytes, uint32_t inst_length);
 
 /*
  * Decode the instruction fetched into 'vie' so it can be emulated.
diff --git a/hypervisor/arch/x86/guest/vcpu.c b/hypervisor/arch/x86/guest/vcpu.c
index 185904fbd..016a7d6ec 100644
--- a/hypervisor/arch/x86/guest/vcpu.c
+++ b/hypervisor/arch/x86/guest/vcpu.c
@@ -136,7 +136,8 @@ int create_vcpu(int cpu_id, struct vm *vm, struct vcpu **rtn_vcpu_handle)
 
 int start_vcpu(struct vcpu *vcpu)
 {
-	uint64_t rip, instlen;
+	uint32_t instlen;
+	uint64_t rip;
 	struct run_context *cur_context =
 		&vcpu->arch_vcpu.contexts[vcpu->arch_vcpu.cur_context];
 	int64_t status = 0;
diff --git a/hypervisor/common/hv_main.c b/hypervisor/common/hv_main.c
index 6bad1a806..8fb5aabfa 100644
--- a/hypervisor/common/hv_main.c
+++ b/hypervisor/common/hv_main.c
@@ -50,13 +50,12 @@ static void run_vcpu_pre_work(struct vcpu *vcpu)
 
 void vcpu_thread(struct vcpu *vcpu)
 {
-	uint64_t vmexit_begin, vmexit_end;
-	uint16_t exit_reason;
+	uint64_t vmexit_begin = 0, vmexit_end = 0;
+	uint16_t basic_exit_reason = 0;
 	uint64_t tsc_aux_hyp_cpu = vcpu->pcpu_id;
 	struct vm_exit_dispatch *vmexit_hdlr;
 	int ret = 0;
 
-	vmexit_begin = vmexit_end = exit_reason = 0;
 	/* If vcpu is not launched, we need to do init_vmcs first */
 	if (!vcpu->launched)
 		init_vmcs(vcpu);
@@ -87,7 +86,7 @@ void vcpu_thread(struct vcpu *vcpu)
 
 		vmexit_end = rdtsc();
 		if (vmexit_begin > 0)
-			per_cpu(vmexit_time, vcpu->pcpu_id)[exit_reason]
+			per_cpu(vmexit_time, vcpu->pcpu_id)[basic_exit_reason]
 				+= (vmexit_end - vmexit_begin);
 		TRACE_2L(TRACE_VM_ENTER, 0, 0);
 
@@ -114,12 +113,12 @@ void vcpu_thread(struct vcpu *vcpu)
 		ASSERT(vmexit_hdlr != 0,
 				"Unable to dispatch VM exit handler!");
 
-		exit_reason = vcpu->arch_vcpu.exit_reason & 0xFFFF;
-		per_cpu(vmexit_cnt, vcpu->pcpu_id)[exit_reason]++;
-		TRACE_2L(TRACE_VM_EXIT, exit_reason,
+		basic_exit_reason = vcpu->arch_vcpu.exit_reason & 0xFFFF;
+		per_cpu(vmexit_cnt, vcpu->pcpu_id)[basic_exit_reason]++;
+		TRACE_2L(TRACE_VM_EXIT, basic_exit_reason,
 		vcpu->arch_vcpu.contexts[vcpu->arch_vcpu.cur_context].rip);
 
-		if (exit_reason == VMX_EXIT_REASON_EXTERNAL_INTERRUPT) {
+		if (basic_exit_reason == VMX_EXIT_REASON_EXTERNAL_INTERRUPT) {
 			/* Handling external_interrupt
 			 * should disable intr
 			 */
diff --git a/hypervisor/include/arch/x86/guest/vcpu.h b/hypervisor/include/arch/x86/guest/vcpu.h
index e13df9d3b..c8cc1ab8e 100644
--- a/hypervisor/include/arch/x86/guest/vcpu.h
+++ b/hypervisor/include/arch/x86/guest/vcpu.h
@@ -214,10 +214,10 @@ struct vcpu_arch {
 	uint64_t msr_tsc_aux;
 
 	/* VCPU context state information */
-	uint64_t exit_reason;
+	uint32_t exit_reason;
 	uint64_t exit_interrupt_info;
 	uint64_t exit_qualification;
-	uint8_t inst_len;
+	uint32_t inst_len;
 
 	/* Information related to secondary / AP VCPU start-up */
 	uint8_t cpu_mode;