fix a few bugs in scheduling and synchronization, separate OVMF_VARS for debug

code/kernel/ke_mutex.c

@@ -24,46 +24,42 @@ KSTATUS KeAcquireMutex(MUTEX* mutex) {
     THREAD* self = KeCurrentThread();
 
     for (;;) {
-        KeAcquireSpinlock(&mutex->Lock);
+        uintptr_t flags = KeAcquireSpinlock(&mutex->Lock);
         if (!mutex->Owner) {
             mutex->Owner = self;
-            KeReleaseSpinlock(&mutex->Lock);
+            KeReleaseSpinlock(&mutex->Lock, flags);
             return STATUS_SUCCESS;
         }
-        // Already owned - add self to wait list and block.
         ListInsertTail(&mutex->WaitList, &self->SchedulerLink);
-        KeReleaseSpinlock(&mutex->Lock);
+        KeReleaseSpinlock(&mutex->Lock, flags);
         KeBlockThread(self, &mutex->Header);
-        // KeBlockThread calls KeYield; when we return here we've been
-        // unblocked by KeReleaseMutex - loop back and try to own it.
     }
 }
 
 KSTATUS KeTryAcquireMutex(MUTEX* mutex) {
     if (!mutex) return STATUS_INVALID_PARAMETER;
     THREAD* self = KeCurrentThread();
-    KeAcquireSpinlock(&mutex->Lock);
+    uintptr_t flags = KeAcquireSpinlock(&mutex->Lock);
     if (!mutex->Owner) {
         mutex->Owner = self;
-        KeReleaseSpinlock(&mutex->Lock);
+        KeReleaseSpinlock(&mutex->Lock, flags);
         return STATUS_SUCCESS;
     }
-    KeReleaseSpinlock(&mutex->Lock);
+    KeReleaseSpinlock(&mutex->Lock, flags);
     return STATUS_FAILURE;
 }
 
 void KeReleaseMutex(MUTEX* mutex) {
     if (!mutex) return;
-    KeAcquireSpinlock(&mutex->Lock);
+    uintptr_t flags = KeAcquireSpinlock(&mutex->Lock);
     mutex->Owner = (struct THREAD *)0;
 
-    // Wake the first waiter, if any.
     if (!LIST_IS_EMPTY(&mutex->WaitList)) {
         LIST_ENTRY* node = ListPopHead(&mutex->WaitList);
         THREAD* waiter   = CONTAINING_RECORD(node, THREAD, SchedulerLink);
-        KeReleaseSpinlock(&mutex->Lock);
+        KeReleaseSpinlock(&mutex->Lock, flags);
         KeUnblockThread(waiter);
         return;
     }
-    KeReleaseSpinlock(&mutex->Lock);
+    KeReleaseSpinlock(&mutex->Lock, flags);
 }