diff --git a/kernel/riscv.h b/kernel/riscv.h
index c934309..47d5397 100644
--- a/kernel/riscv.h
+++ b/kernel/riscv.h
@@ -429,6 +429,16 @@ typedef u64 *pagetable_t; // 512 PTEs
 /**
  * Page Table Entry Flags
  */
+/** Valid */
+#define PTE_V (1L << 0)
+/** Readable */
+#define PTE_R (1L << 1)
+/** Writable */
+#define PTE_W (1L << 2)
+/** Executable */
+#define PTE_X (1L << 3)
+/** User-accessible */
+#define PTE_U (1L << 4)
 
 #define PTE_V (1L << 0) /** PTE Valid */
 #define PTE_R (1L << 1) /** PTE Readable */