More detailed error handling on msr writes

diff --git a/palacios/src/palacios/vmm_msr.c b/palacios/src/palacios/vmm_msr.c
index bb1b062..2329f53 100644 (file)
--- a/palacios/src/palacios/vmm_msr.c
+++ b/palacios/src/palacios/vmm_msr.c
@@ -64,9 +64,13 @@ int v3_handle_msr_write(struct guest_info * info) {
        msr_val.lo = info->vm_regs.rax;
        msr_val.hi = info->vm_regs.rdx;
        
-       if (hook->write(info, msr_num, msr_val, hook->priv_data) == -1) {
-           PrintError("Error in MSR hook Write\n");
-           return -1;
+       if (hook->write) {
+           if (hook->write(info, msr_num, msr_val, hook->priv_data) == -1) {
+               PrintError("Error in MSR hook Write\n");
+               return -1;
+           }
+       } else {
+           PrintError("No write hook exists for msr 0x%x\n",msr_num);
        }
     }