diff --git a/kern/pmap.c b/kern/pmap.c
index 58c0a41..2c590f2 100644
--- a/kern/pmap.c
+++ b/kern/pmap.c
@@ -183,8 +183,8 @@ mem_init(void)
 	// Your code goes here:
 	boot_map_region(kern_pgdir,
 			UPAGES, ROUNDUP(pages_size, PGSIZE),
-			PADDR(pages), PTE_W);
-	kern_pgdir[PDX(UPAGES)] |= PTE_U | PTE_P;
+			PADDR(pages), PTE_U);
+	kern_pgdir[PDX(UPAGES)] |= PTE_U;
 	kern_pgdir[PDX(UPAGES)] &= ~PTE_W;
 
 	//////////////////////////////////////////////////////////////////////
@@ -196,7 +196,7 @@ mem_init(void)
 	// LAB 3: Your code here.
 	boot_map_region(kern_pgdir,
 		UENVS, ROUNDUP(envs_size, PGSIZE),
-		PADDR(envs), PTE_W);
+		PADDR(envs), PTE_U);
 	kern_pgdir[PDX(UENVS)] |= PTE_U;
 	kern_pgdir[PDX(UPAGES)] &= ~PTE_W;