diff --git a/arch/ia64/kernel/entry.S b/arch/ia64/kernel/entry.S
index 7ef0c594f5ed..d435f4a7a96c 100644
--- a/arch/ia64/kernel/entry.S
+++ b/arch/ia64/kernel/entry.S
@@ -499,6 +499,7 @@ GLOBAL_ENTRY(prefetch_stack)
 END(prefetch_stack)
 
 GLOBAL_ENTRY(kernel_execve)
+	rum psr.ac
 	mov r15=__NR_execve			// put syscall number in place
 	break __BREAK_SYSCALL
 	br.ret.sptk.many rp
diff --git a/arch/ia64/kernel/head.S b/arch/ia64/kernel/head.S
index 66e491d8baac..59301c472800 100644
--- a/arch/ia64/kernel/head.S
+++ b/arch/ia64/kernel/head.S
@@ -260,7 +260,7 @@ start_ap:
 	 * Switch into virtual mode:
 	 */
 	movl r16=(IA64_PSR_IT|IA64_PSR_IC|IA64_PSR_DT|IA64_PSR_RT|IA64_PSR_DFH|IA64_PSR_BN \
-		  |IA64_PSR_DI)
+		  |IA64_PSR_DI|IA64_PSR_AC)
 	;;
 	mov cr.ipsr=r16
 	movl r17=1f