Got decent exception handling

kernel/include/exceptions.h

@@ -0,0 +1,24 @@
+#ifndef _EXCEPTIONS_H
+#define _EXCEPTIONS_H
+
+#include "isr.h"
+
+#define EXCEPTION_DE 0
+#define EXCEPTION_BP 3
+#define EXCEPTION_OF 4
+#define EXCEPTION_BR 5
+#define EXCEPTION_UD 6
+#define EXCEPTION_NM 7
+#define EXCEPTION_DF 8
+#define EXCEPTION_GP 13
+#define EXCEPTION_PF 14
+#define EXCEPTION_AC 17
+
+typedef void (*exception_handler_ptr)(struct isr_int_frame* iframe, bool user);
+
+const extern char* exception_strings[];
+
+int  exception_init(void);
+void exception_handle(struct isr_int_frame* iframe);
+
+#endif

kernel/include/paging.h

@@ -9,6 +9,7 @@
 #define PTE_FLAG_USER		(1UL << 2) // User-mode (DPL3) access allowed
 #define PTE_FLAG_PWT		(1UL << 3) // Page write-thru
 #define PTE_FLAG_NOCACHE	(1UL << 4) // Cache disable
+#define PTE_FLAG_FETCH		(1UL << 4) // Fetch
 #define PTE_FLAG_ACCESSED	(1UL << 5) // Indicates whether page was read/written
 #define PTE_FLAG_DIRTY		(1UL << 6) // Indicates whether page was written to (valid for PT only)
 #define PTE_FLAG_PAT		(1UL << 7) // Page Attribute Table (valid for PT only)