diff --git a/fs/proc/task_mmu.c b/fs/proc/task_mmu.c
index 541392a..c216360 100644
--- a/fs/proc/task_mmu.c
+++ b/fs/proc/task_mmu.c
@@ -679,6 +679,9 @@ static void show_smap_vma_flags(struct seq_file *m, struct vm_area_struct *vma)
 		[ilog2(VM_PKEY_BIT1)]	= "",
 		[ilog2(VM_PKEY_BIT2)]	= "",
 		[ilog2(VM_PKEY_BIT3)]	= "",
+#if VM_PKEY_BIT4
+		[ilog2(VM_PKEY_BIT4)]	= "",
+#endif
 #endif /* CONFIG_ARCH_HAS_PKEYS */
 	};
 	size_t i;
diff --git a/include/linux/mm.h b/include/linux/mm.h
index c6a6f24..fc25929 100644
--- a/include/linux/mm.h
+++ b/include/linux/mm.h
@@ -231,9 +231,14 @@ extern unsigned int kobjsize(const void *objp);
 #ifdef CONFIG_ARCH_HAS_PKEYS
 # define VM_PKEY_SHIFT	VM_HIGH_ARCH_BIT_0
 # define VM_PKEY_BIT0	VM_HIGH_ARCH_0	/* A protection key is a 4-bit value */
-# define VM_PKEY_BIT1	VM_HIGH_ARCH_1
+# define VM_PKEY_BIT1	VM_HIGH_ARCH_1	/* on x86 and 5-bit value on ppc64   */
 # define VM_PKEY_BIT2	VM_HIGH_ARCH_2
 # define VM_PKEY_BIT3	VM_HIGH_ARCH_3
+#ifdef CONFIG_PPC
+# define VM_PKEY_BIT4  VM_HIGH_ARCH_4
+#else
+# define VM_PKEY_BIT4  0
+#endif
 #endif /* CONFIG_ARCH_HAS_PKEYS */
 
 #if defined(CONFIG_X86)