diff --git a/src/thread/thread.c b/src/thread/thread.c
index 402e0ec..adba9e8 100644
--- a/src/thread/thread.c
+++ b/src/thread/thread.c
@@ -103,7 +103,7 @@ int thread_create(thread_t* newthread, void* (*func)(void*), void* funcarg)
 {
     TRACE("Create a new thread that execute function %p", func);
     struct context_entry* new_entry = malloc(sizeof(*new_entry));
-    memset(new_entry, 0, sizeof(*new_entry));
+    memset(new_entry->stack, 0, STACK_SIZE);
 
     getcontext(&new_entry->context);
 
@@ -222,7 +222,7 @@ void __attribute__((constructor)) setup_main_thread()
     TRACE("premain");
     // Create an entry for the main thread.
     struct context_entry* main = malloc(sizeof(*main));
-    memset(main, 0, sizeof(*main));
+    // memset(main, 0, sizeof(*main));
     getcontext(&main->context);
     main->id = main;
     main->status = 0;