2 files changed, 20 insertions, 0 deletions

diff --git a/kernel/signal.c b/kernel/signal.c
index 39d122753bac..ef8156a6aad5 100644
--- a/kernel/signal.c
+++ b/kernel/signal.c
@@ -255,6 +255,16 @@ flush_signal_handlers(struct task_struct *t, int force_default)
         }
 }
 
+int unhandled_signal(struct task_struct *tsk, int sig)
+{
+        if (is_init(tsk))
+                return 1;
+        if (tsk->ptrace & PT_PTRACED)
+                return 0;
+        return (tsk->sighand->action[sig-1].sa.sa_handler == SIG_IGN) ||
+                (tsk->sighand->action[sig-1].sa.sa_handler == SIG_DFL);
+}
+
 
 /* Notify the system that a driver wants to block all signals for this
  * process, and wants to be notified if any signals at all were to be
diff --git a/kernel/sysctl.c b/kernel/sysctl.c
index 222299844ad1..ddebf3f2affe 100644
--- a/kernel/sysctl.c
+++ b/kernel/sysctl.c
@@ -1203,6 +1203,16 @@ static ctl_table fs_table[] = {
 };
 
 static ctl_table debug_table[] = {
+#ifdef CONFIG_X86
+        {
+                .ctl_name       = CTL_UNNUMBERED,
+                .procname       = "exception-trace",
+                .data           = &show_unhandled_signals,
+                .maxlen         = sizeof(int),
+                .mode           = 0644,
+                .proc_handler   = proc_dointvec
+        },
+#endif
         { .ctl_name = 0 }
 };