+#ifdef CONFIG_DEBUG_USER_ASCE
+void debug_user_asce(void)
+{
+ unsigned long cr1, cr7;
+
+ __ctl_store(cr1, 1, 1);
+ __ctl_store(cr7, 7, 7);
+ if (cr1 == S390_lowcore.kernel_asce && cr7 == S390_lowcore.user_asce)
+ return;
+ panic("incorrect ASCE on kernel exit\n"
+ "cr1: %016lx cr7: %016lx\n"
+ "kernel: %016llx user: %016llx\n",
+ cr1, cr7, S390_lowcore.kernel_asce, S390_lowcore.user_asce);
+}
+#endif /*CONFIG_DEBUG_USER_ASCE */
+