summaryrefslogtreecommitdiff
path: root/arch/s390/lib/uaccess.c
diff options
context:
space:
mode:
Diffstat (limited to 'arch/s390/lib/uaccess.c')
-rw-r--r--arch/s390/lib/uaccess.c16
1 files changed, 16 insertions, 0 deletions
diff --git a/arch/s390/lib/uaccess.c b/arch/s390/lib/uaccess.c
index 0ffbe1fad72a..e8f642446fed 100644
--- a/arch/s390/lib/uaccess.c
+++ b/arch/s390/lib/uaccess.c
@@ -16,6 +16,22 @@
#include <asm/mmu_context.h>
#include <asm/facility.h>
+#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 */
+
#ifndef CONFIG_HAVE_MARCH_Z10_FEATURES
static DEFINE_STATIC_KEY_FALSE(have_mvcos);