palacios/src/geekos/svm_ctrl_regs.c

   1 #include <geekos/svm_ctrl_regs.h>
   2 #include <geekos/vmm_mem.h>
   3 #include <geekos/vmm.h>
   4 #include <geekos/vmcb.h>
   5 #include <geekos/vmm_emulate.h>
   6 #include <geekos/vm_guest_mem.h>
   7
   8 int handle_cr0_write(struct guest_info * info, ullong_t * new_cr0) {
   9   //vmcb_ctrl_t * ctrl_area = GET_VMCB_CTRL_AREA((vmcb_t *)(info->vmm_data));
  10   vmcb_saved_state_t * guest_state = GET_VMCB_SAVE_STATE_AREA((vmcb_t*)(info->vmm_data));
  11   char instr[15];
  12
  13
  14
  15
  16   if (info->cpu_mode == REAL) {
  17     read_guest_pa_memory(info, (addr_t)guest_state->rip, 15, instr);
  18     int index = 0;
  19
  20     while (is_prefix_byte(instr[index])) {
  21       PrintDebug("instr(%d): 0x%x\n", index, instr[index]);
  22       index++;
  23     }
  24     PrintDebug("instr(%d): 0x%x\n", index, instr[index]);
  25     PrintDebug("instr(%d): 0x%x\n", index+1, instr[index + 1]);
  26
  27     if ((instr[index] == cr_access_byte) &&
  28         (instr[index + 1] == lmsw_byte) &&
  29         (MODRM_REG(instr[index + 2]) == lmsw_reg_byte)) {
  30
  31       addr_t first_operand;
  32       addr_t second_operand;
  33
  34       // LMSW
  35       // decode mod/RM
  36       index += 2;
  37
  38
  39       if (decode_operands16(&(info->vm_regs), instr + index, &first_operand, &second_operand, REG16) != 0) {
  40         // error... don't know what to do
  41         return -1;
  42       }
  43
  44       PrintDebug("FirstOperand addr: %x, RAX addr: %x\n", first_operand, &(info->vm_regs.rax));
  45
  46
  47
  48
  49     } else if ((instr[index] == cr_access_byte) &&
  50                (instr[index + 1] == clts_byte)) {
  51       // CLTS
  52     } else {
  53       // unsupported instruction, GPF the guest
  54       return -1;
  55     }
  56
  57
  58   }
  59
  60
  61   return 0;
  62 }
  63
  64