Floating point context-switching and checkpoint/load

[palacios.git] / palacios / src / palacios / vmm_shadow_paging.c

diff --git a/palacios/src/palacios/vmm_shadow_paging.c b/palacios/src/palacios/vmm_shadow_paging.c
index d87ee11..38dcc64 100644 (file)
--- a/palacios/src/palacios/vmm_shadow_paging.c
+++ b/palacios/src/palacios/vmm_shadow_paging.c
@@ -170,9 +170,15 @@ int v3_init_shdw_pg_state(struct guest_info * core) {
 
 
 int v3_deinit_shdw_pg_state(struct guest_info * core) {
-    struct v3_shdw_pg_impl * impl = core->vm_info->shdw_impl.current_impl;
+    struct v3_shdw_pg_impl * impl = NULL;
+
+    if (!core || !core->vm_info) {
+        return -1;
+    }
 
-    if (impl->local_deinit(core) == -1) {
+    impl = core->vm_info->shdw_impl.current_impl;
+
+    if (impl && impl->local_deinit(core) == -1) {
        PrintError(core->vm_info, core, "Error deinitializing shadow paging state\n");
        return -1;
     }
@@ -191,9 +197,27 @@ int v3_init_shdw_impl(struct v3_vm_info * vm) {
     struct v3_shdw_pg_impl * impl = NULL;
    
     PrintDebug(vm, VCORE_NONE, "Checking if shadow paging requested.\n");
-    if ((pg_mode != NULL) && (strcasecmp(pg_mode, "nested") == 0)) {
-       PrintDebug(vm, VCORE_NONE, "Nested paging specified - not initializing shadow paging.\n");
-       return 0;
+    if (pg_mode == NULL) { 
+       V3_Print(vm, VCORE_NONE, "No paging mode specified, assuming shadow with defaults\n");
+       pg_mode = "shadow";
+    } else {
+       if (strcasecmp(pg_mode, "nested") == 0) {
+           // this check is repeated here (compare to vmm_config's determine paging mode) since
+           // shadow paging initialization *precedes* per-core pre-config.
+           extern v3_cpu_arch_t v3_mach_type;
+           if ((v3_mach_type == V3_SVM_REV3_CPU) || 
+               (v3_mach_type == V3_VMX_EPT_CPU) ||
+               (v3_mach_type == V3_VMX_EPT_UG_CPU)) {
+               PrintDebug(vm, VCORE_NONE, "Nested paging specified on machine that supports it - not initializing shadow paging\n");
+               return 0;
+           } else {
+               V3_Print(vm, VCORE_NONE, "Nested paging specified but machine does not support it - falling back to shadow paging with defaults\n");
+               pg_mode = "shadow";
+           }
+       } else if (strcasecmp(pg_mode, "shadow") != 0) { 
+           V3_Print(vm, VCORE_NONE, "Unknown paging mode '%s' specified - falling back to shadow paging with defaults\n",pg_mode);
+           pg_mode = "shadow";
+       }
     }
 
     if (pg_strat == NULL) {