added debugging

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

diff --git a/palacios/src/palacios/vmm_sym_swap.c b/palacios/src/palacios/vmm_sym_swap.c
index 5c8cad8..0fbb853 100644 (file)
--- a/palacios/src/palacios/vmm_sym_swap.c
+++ b/palacios/src/palacios/vmm_sym_swap.c
@@ -155,6 +155,10 @@ int v3_swap_flush(struct guest_info * info) {
     swap_state->flushes++;
 #endif
 
+    if (!ht_iter) {
+       PrintError("NULL iterator in swap flush!! Probably will crash soon...\n");
+    }
+
     while (ht_iter->entry) {
        struct shadow_pointer * tmp_shdw_ptr = NULL;
        struct shadow_pointer * shdw_ptr = NULL;
@@ -164,12 +168,16 @@ int v3_swap_flush(struct guest_info * info) {
        // we can leave the list_head structures and reuse them for the next round
        
        list_for_each_entry_safe(shdw_ptr, tmp_shdw_ptr, shdw_ptr_list, node) {
+           if (shadw_ptr == NULL) {
+               PrintError("Null shadow pointer in swap flush!! Probably crashing soon...\n");
+           }
+
            // Trigger faults for next shadow access
            shdw_ptr->shadow_pte->present = 0;
            
            // Delete entry from list
            list_del(&(shdw_ptr->node));
-           V3_Free(shdw_ptr);      
+           V3_Free(shdw_ptr);
        }
 
        v3_htable_iter_advance(ht_iter);