context switch seems to do stuff

arch/context.cc

@@ -8,8 +8,8 @@ void panic(){
 
 void prepareContext(void* tos, Context& context, void (*kickoff)(void*),
                     void* param1) {
-    ((uint64_t*)tos)[0] = (uint64_t)panic;
+    ((uint64_t*)tos)[-1] = (uint64_t)panic;
-    ((uint64_t*)tos)[-1] = (uint64_t)kickoff;
+    ((uint64_t*)tos)[0] = (uint64_t)kickoff;
     context.rsp = tos;
     context.rbx = 0;
     context.rbp = 0;