X-Git-Url: http://v3vee.org/palacios/gitweb/gitweb.cgi?a=blobdiff_plain;f=palacios%2Fsrc%2Fpalacios%2Fvmm_msr.c;h=b96018739f2842b69569df881d0fed38a0c1a1bf;hb=7ebb801201cc0c40f769db676e69b6e7394b08b5;hp=290398ecbbe2366afe1d60b973f36e7570dc11d3;hpb=5e5c8ee949fa45116d58b904fc11aab082f61607;p=palacios.releases.git

diff --git a/palacios/src/palacios/vmm_msr.c b/palacios/src/palacios/vmm_msr.c
index 290398e..b960187 100644
--- a/palacios/src/palacios/vmm_msr.c
+++ b/palacios/src/palacios/vmm_msr.c
@@ -59,14 +59,18 @@ int v3_handle_msr_write(struct guest_info * info) {
     hook = v3_get_msr_hook(info->vm_info, msr_num);
 
     if (hook == NULL) {
-        PrintError("Write to unhooked MSR 0x%x\n", msr_num);
+	v3_msr_unhandled_write(info, msr_num, msr_val, NULL);
     } else {
 	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);
 	}
     }
 
@@ -86,7 +90,7 @@ int v3_handle_msr_read(struct guest_info * info) {
     hook = v3_get_msr_hook(info->vm_info, msr_num);
     
     if (hook == NULL) {
-        PrintError("Read from unhooked MSR 0x%x\n", msr_num);	
+	v3_msr_unhandled_read(info, msr_num, &msr_val, NULL);
     } else {
 	if (hook->read(info, msr_num, &msr_val, hook->priv_data) == -1) {
 	    PrintError("Error in MSR hook Read\n");
@@ -101,6 +105,24 @@ int v3_handle_msr_read(struct guest_info * info) {
     return 0;
 }
 
+
+
+int v3_msr_unhandled_read(struct guest_info * core, uint32_t msr, struct v3_msr * dst, void * priv_data) {
+    V3_Print("Palacios: Unhandled MSR Read (MSR=0x%x) - returning zero\n", msr);
+
+    dst->value = 0;
+
+    // should produce GPF for unsupported msr
+    return 0;
+}
+
+int v3_msr_unhandled_write(struct guest_info * core, uint32_t msr, struct v3_msr src, void * priv_data) {
+    V3_Print("Palacios: Unhandled MSR Write (MSR=0x%x) - ignored\n", msr);
+    // should produce GPF for unsupported msr
+    return 0;
+}
+
+
 int v3_hook_msr(struct v3_vm_info * vm, uint32_t msr, 
 		int (*read)(struct guest_info * core, uint32_t msr, struct v3_msr * dst, void * priv_data),
 		int (*write)(struct guest_info * core, uint32_t msr, struct v3_msr src, void * priv_data),
@@ -134,6 +156,10 @@ int v3_hook_msr(struct v3_vm_info * vm, uint32_t msr,
     return 0;
 }
 
+
+
+
+
 static int free_hook(struct v3_vm_info * vm, struct v3_msr_hook * hook) {
     list_del(&(hook->link));