diff --git a/arch/arm/kernel/head-nommu.S b/arch/arm/kernel/head-nommu.S
index dd546d65a383..7a9b86978ee1 100644
--- a/arch/arm/kernel/head-nommu.S
+++ b/arch/arm/kernel/head-nommu.S
@@ -177,7 +177,7 @@ M_CLASS(streq	r3, [r12, #PMSAv8_MAIR1])
 	bic	r0, r0, #CR_I
 #endif
 	mcr	p15, 0, r0, c1, c0, 0		@ write control reg
-	isb
+	instr_sync
 #elif defined (CONFIG_CPU_V7M)
 #ifdef CONFIG_ARM_MPU
 	ldreq	r3, [r12, MPU_CTRL]
diff --git a/arch/arm/mm/init.c b/arch/arm/mm/init.c
index c186474422f3..0cc8e04295a4 100644
--- a/arch/arm/mm/init.c
+++ b/arch/arm/mm/init.c
@@ -736,20 +736,29 @@ static int __mark_rodata_ro(void *unused)
 	return 0;
 }
 
+static int kernel_set_to_readonly __read_mostly;
+
 void mark_rodata_ro(void)
 {
+	kernel_set_to_readonly = 1;
 	stop_machine(__mark_rodata_ro, NULL, NULL);
 	debug_checkwx();
 }
 
 void set_kernel_text_rw(void)
 {
+	if (!kernel_set_to_readonly)
+		return;
+
 	set_section_perms(ro_perms, ARRAY_SIZE(ro_perms), false,
 				current->active_mm);
 }
 
 void set_kernel_text_ro(void)
 {
+	if (!kernel_set_to_readonly)
+		return;
+
 	set_section_perms(ro_perms, ARRAY_SIZE(ro_perms), true,
 				current->active_mm);
 }