decoder fix for cut/paste bug in rm decoding

[palacios.git] / palacios / include / palacios / vmm_instr_decoder.h

diff --git a/palacios/include/palacios/vmm_instr_decoder.h b/palacios/include/palacios/vmm_instr_decoder.h
index 3fe838b..ce494e7 100644 (file)
--- a/palacios/include/palacios/vmm_instr_decoder.h
+++ b/palacios/include/palacios/vmm_instr_decoder.h
@@ -191,6 +191,7 @@ static int get_operand_width(struct guest_info * info, struct x86_instr * instr,
        case XOR_MEM2_8:
        case XOR_IMM2_8:
        case INC_8:
+       case INT:
        case DEC_8:
        case NEG_8:
        case NOT_8:
@@ -310,7 +311,7 @@ static int get_operand_width(struct guest_info * info, struct x86_instr * instr,
                    return -1;
            }
 
-       case INT:
+       //case INT:
        case MOV_DR2:
        case MOV_2DR:
        case MOV_CR2:
@@ -680,7 +681,6 @@ static int decode_rm_operand32(struct guest_info * core,
        }
 
        if (has_sib_byte) {
-           instr_cursor += 1;
            struct sib_byte * sib = (struct sib_byte *)(instr_cursor);
            int scale = 0x1 << sib->scale;
 
@@ -735,6 +735,9 @@ static int decode_rm_operand32(struct guest_info * core,
                case 5:
                    if (modrm->mod != 0) {
                        base_addr += ADDR_MASK(gprs->rbp, 4);
+                   } else {
+                       mod_mode = DISP32;
+                       base_addr = 0;
                    }
                    break;
                case 6:
@@ -887,7 +890,6 @@ int decode_rm_operand64(struct guest_info * core, uint8_t * modrm_instr,
        }
 
        if (has_sib_byte) {
-           instr_cursor += 1;
            struct sib_byte * sib = (struct sib_byte *)(instr_cursor);
            int scale = 0x1 << sib->scale;
            uint8_t index_val = sib->index;
@@ -971,6 +973,9 @@ int decode_rm_operand64(struct guest_info * core, uint8_t * modrm_instr,
                case 5:
                    if (modrm->mod != 0) {
                        base_addr += gprs->rbp;
+                   } else {
+                       mod_mode = DISP32;
+                       base_addr = 0;
                    }
                    break;
                case 6:
@@ -1017,23 +1022,24 @@ int decode_rm_operand64(struct guest_info * core, uint8_t * modrm_instr,
        }
     
 
-       /* 
-          Segments should be ignored 
-          // get appropriate segment
-          if (instr->prefixes.cs_override) {
-          seg = &(core->segments.cs);
-          } else if (instr->prefixes.es_override) {
-          seg = &(core->segments.es);
-          } else if (instr->prefixes.ss_override) {
-          seg = &(core->segments.ss);
-          } else if (instr->prefixes.fs_override) {
-          seg = &(core->segments.fs);
-          } else if (instr->prefixes.gs_override) {
-          seg = &(core->segments.gs);
-          } else {
-          seg = &(core->segments.ds);
-          }
-       */
+       
+       //Segments should be ignored 
+       // get appropriate segment
+
+       if (instr->prefixes.cs_override) {
+           seg = &(core->segments.cs);
+       } else if (instr->prefixes.es_override) {
+           seg = &(core->segments.es);
+       } else if (instr->prefixes.ss_override) {
+           seg = &(core->segments.ss);
+       } else if (instr->prefixes.fs_override) {
+           seg = &(core->segments.fs);
+       } else if (instr->prefixes.gs_override) {
+           seg = &(core->segments.gs);
+       } else {
+           seg = &(core->segments.ds);
+       }
+       
 
        operand->operand = ADDR_MASK(get_addr_linear(core, base_addr, seg), 
                                     get_addr_width(core, instr));
@@ -1061,7 +1067,7 @@ static int decode_rm_operand(struct guest_info * core,
        case REAL:
            return decode_rm_operand16(core, instr_ptr, instr, operand, reg_code);
        case LONG:
-           if (instr->prefixes.rex_op_size) {
+           if (instr->prefixes.rex) {
                return decode_rm_operand64(core, instr_ptr, instr, operand, reg_code);
            }
        case PROTECTED: