Fix weird startup crashes in debug mode

kernel/amd64/smp.c

@@ -102,10 +102,10 @@ static void smp_bootstrap (struct limine_mp_info* mp_info) {
 
   DEBUG ("CPU %u is online!\n", thiscpu->id);
 
-  atomic_fetch_sub (&cpu_counter, 1);
-
   cpu->kproc = kproc_create ();
 
+  atomic_fetch_sub (&cpu_counter, 1);
+
   __asm__ volatile ("sti");
 
   struct reschedule_ctx rctx;
@@ -116,6 +116,9 @@ static void smp_bootstrap (struct limine_mp_info* mp_info) {
 
   spin_lock (&spin_proc->cpu->lock, &fc);
   do_sched (spin_proc, &spin_proc->cpu->lock, fc);
+
+  for (;;)
+    ;
 }
 
 /// Initialize SMP subsystem for AMD64. Start AP CPUs
@@ -133,7 +136,7 @@ void smp_init (void) {
   DEBUG ("Waiting for other CPUs:\n");
 
   while (atomic_load (&cpu_counter) > 0)
-    debugprintf (".\n");
+    ;
 
   DEBUG ("All CPUs are up!\n");
 }

kernel/mm/_malloc_port.c

@@ -25,6 +25,7 @@
 #define HAVE_MORECORE    0
 #define NO_MALLOC_STATS  1
 #define USE_LOCKS        1
+#define USE_SPIN_LOCKS   1
 #define MALLOC_FAILURE_ACTION                                                                      \
   do {                                                                                             \
     DEBUG ("malloc failure\n");                                                                    \