hv: bugfix - MMIO access size was not properly initialized.

- MMIO access size is not initialized before
  instruction emulation.
- rename 'analyze_instruction()' to 'decode_instruction()'

Signed-off-by: Yonghua Huang <yonghua.huang@intel.com>

Author: yonghuah

hypervisor/arch/x86/ept.c

@@ -339,10 +339,6 @@ static int dm_emulate_mmio_pre(struct vcpu *vcpu, uint64_t exit_qual)
 {
 	int status;
 
-	status = analyze_instruction(vcpu, &vcpu->mmio);
-	if (status != 0)
-		return status;
-
 	if (vcpu->mmio.read_write == HV_MEM_IO_WRITE) {
 		status = emulate_instruction(vcpu, &vcpu->mmio);
 		if (status != 0)
@@ -404,6 +400,9 @@ int ept_violation_vmexit_handler(struct vcpu *vcpu)
 	 */
 	mmio->paddr = gpa;
 
+	if (decode_instruction(vcpu, mmio) != 0)
+		goto out;
+
 	list_for_each(pos, &vcpu->vm->mmio_list) {
 		mmio_handler = list_entry(pos, struct mem_io_node, list);
 		if ((mmio->paddr + mmio->access_size <=
@@ -419,9 +418,6 @@ int ept_violation_vmexit_handler(struct vcpu *vcpu)
 			return -EIO;
 		}
 
-		if (analyze_instruction(vcpu, mmio) != 0)
-			goto out;
-
 		if (mmio->read_write == HV_MEM_IO_WRITE) {
 			if (emulate_instruction(vcpu, mmio) != 0)
 				goto out;

hypervisor/arch/x86/guest/instr_emul.h

@@ -90,6 +90,6 @@ int vmm_decode_instruction(struct vcpu *vcpu, uint64_t gla,
 		enum vm_cpu_mode cpu_mode, int csd, struct vie *vie);
 
 int emulate_instruction(struct vcpu *vcpu, struct mem_io *mmio);
-int analyze_instruction(struct vcpu *vcpu, struct mem_io *mmio);
+int decode_instruction(struct vcpu *vcpu, struct mem_io *mmio);
 
 #endif	/* _VMM_INSTRUCTION_EMUL_H_ */

hypervisor/arch/x86/guest/instr_emul_wrapper.c

@@ -380,7 +380,7 @@ void vm_gva2gpa(struct vcpu *vcpu, uint64_t gva, uint64_t *gpa)
 		vcpu->arch_vcpu.contexts[vcpu->arch_vcpu.cur_context].cr3, gva);
 }
 
-int analyze_instruction(struct vcpu *vcpu, struct mem_io *mmio)
+int decode_instruction(struct vcpu *vcpu, struct mem_io *mmio)
 {
 	uint64_t guest_rip_gva, guest_rip_gpa;
 	char *guest_rip_hva;

hypervisor/arch/x86/guest/vlapic.c

@@ -2178,7 +2178,7 @@ int apic_access_vmexit_handler(struct vcpu *vcpu)
 
 	vlapic = vcpu->arch_vcpu.vlapic;
 
-	analyze_instruction(vcpu, &vcpu->mmio);
+	decode_instruction(vcpu, &vcpu->mmio);
 	if (access_type == 1) {
 		if (!emulate_instruction(vcpu, &vcpu->mmio))
 			vlapic_write(vlapic, 1, offset, vcpu->mmio.value);