diff --git a/sys/kern/kern_kse.c b/sys/kern/kern_kse.c
index 7ec5b57dcf7a..183b60729f33 100644
--- a/sys/kern/kern_kse.c
+++ b/sys/kern/kern_kse.c
@@ -1425,44 +1425,50 @@ thread_schedule_upcall(struct thread *td, struct kse_upcall *ku)
 	return (td2);	/* bogus.. should be a void function */
 }
 
-/*
- * Schedule an upcall to notify a KSE process recieved signals.
- *
- * XXX - Modifying a sigset_t like this is totally bogus.
- */
-struct thread *
-signal_upcall(struct proc *p, int sig)
+void
+thread_signal_add(struct thread *td, int sig)
 {
-#if 0
-	struct thread *td, *td2;
-	struct kse *ke;
+	struct kse_upcall *ku;
+	struct proc *p;
 	sigset_t ss;
 	int error;
 
-#endif
-	PROC_LOCK_ASSERT(p, MA_OWNED);
-return (NULL);
-#if 0
-	td = FIRST_THREAD_IN_PROC(p);
-	ke = td->td_kse;
+	PROC_LOCK_ASSERT(td->td_proc, MA_OWNED);
+	td = curthread;
+	ku = td->td_upcall;
+	p = td->td_proc;
+
 	PROC_UNLOCK(p);
-	error = copyin(&ke->ke_mailbox->km_sigscaught, &ss, sizeof(sigset_t));
-	PROC_LOCK(p);
+	error = copyin(&ku->ku_mailbox->km_sigscaught, &ss, sizeof(sigset_t));
 	if (error)
-		return (NULL);
+		goto error;
+
 	SIGADDSET(ss, sig);
-	PROC_UNLOCK(p);
-	error = copyout(&ss, &ke->ke_mailbox->km_sigscaught, sizeof(sigset_t));
-	PROC_LOCK(p);
+
+	error = copyout(&ss, &ku->ku_mailbox->km_sigscaught, sizeof(sigset_t));
 	if (error)
-		return (NULL);
-	if (td->td_standin == NULL)
-		thread_alloc_spare(td, NULL);
+		goto error;
+
+	PROC_LOCK(p);
+	return;
+error:
+	PROC_LOCK(p);
+	sigexit(td, SIGILL);
+}
+
+
+/*
+ * Schedule an upcall to notify a KSE process recieved signals.
+ *
+ */
+void
+thread_signal_upcall(struct thread *td)
+{
 	mtx_lock_spin(&sched_lock);
-	td2 = thread_schedule_upcall(td, ke); /* Bogus JRE */
+	td->td_flags |= TDF_UPCALLING;
 	mtx_unlock_spin(&sched_lock);
-	return (td2);
-#endif
+
+	return;
 }
 
 /*
diff --git a/sys/kern/kern_sig.c b/sys/kern/kern_sig.c
index 8aaf3d9daba5..80df09cff3d0 100644
--- a/sys/kern/kern_sig.c
+++ b/sys/kern/kern_sig.c
@@ -1910,9 +1910,10 @@ postsig(sig)
 			p->p_sig = 0;
 		}
 		if (p->p_flag & P_KSES)
-			if (signal_upcall(p, sig))
-				return;
-		(*p->p_sysent->sv_sendsig)(action, sig, &returnmask, code);
+			thread_signal_add(curthread, sig);
+		else
+			(*p->p_sysent->sv_sendsig)(action, sig,
+			    &returnmask, code);
 	}
 }
 
diff --git a/sys/kern/kern_thread.c b/sys/kern/kern_thread.c
index 7ec5b57dcf7a..183b60729f33 100644
--- a/sys/kern/kern_thread.c
+++ b/sys/kern/kern_thread.c
@@ -1425,44 +1425,50 @@ thread_schedule_upcall(struct thread *td, struct kse_upcall *ku)
 	return (td2);	/* bogus.. should be a void function */
 }
 
-/*
- * Schedule an upcall to notify a KSE process recieved signals.
- *
- * XXX - Modifying a sigset_t like this is totally bogus.
- */
-struct thread *
-signal_upcall(struct proc *p, int sig)
+void
+thread_signal_add(struct thread *td, int sig)
 {
-#if 0
-	struct thread *td, *td2;
-	struct kse *ke;
+	struct kse_upcall *ku;
+	struct proc *p;
 	sigset_t ss;
 	int error;
 
-#endif
-	PROC_LOCK_ASSERT(p, MA_OWNED);
-return (NULL);
-#if 0
-	td = FIRST_THREAD_IN_PROC(p);
-	ke = td->td_kse;
+	PROC_LOCK_ASSERT(td->td_proc, MA_OWNED);
+	td = curthread;
+	ku = td->td_upcall;
+	p = td->td_proc;
+
 	PROC_UNLOCK(p);
-	error = copyin(&ke->ke_mailbox->km_sigscaught, &ss, sizeof(sigset_t));
-	PROC_LOCK(p);
+	error = copyin(&ku->ku_mailbox->km_sigscaught, &ss, sizeof(sigset_t));
 	if (error)
-		return (NULL);
+		goto error;
+
 	SIGADDSET(ss, sig);
-	PROC_UNLOCK(p);
-	error = copyout(&ss, &ke->ke_mailbox->km_sigscaught, sizeof(sigset_t));
-	PROC_LOCK(p);
+
+	error = copyout(&ss, &ku->ku_mailbox->km_sigscaught, sizeof(sigset_t));
 	if (error)
-		return (NULL);
-	if (td->td_standin == NULL)
-		thread_alloc_spare(td, NULL);
+		goto error;
+
+	PROC_LOCK(p);
+	return;
+error:
+	PROC_LOCK(p);
+	sigexit(td, SIGILL);
+}
+
+
+/*
+ * Schedule an upcall to notify a KSE process recieved signals.
+ *
+ */
+void
+thread_signal_upcall(struct thread *td)
+{
 	mtx_lock_spin(&sched_lock);
-	td2 = thread_schedule_upcall(td, ke); /* Bogus JRE */
+	td->td_flags |= TDF_UPCALLING;
 	mtx_unlock_spin(&sched_lock);
-	return (td2);
-#endif
+
+	return;
 }
 
 /*
diff --git a/sys/kern/subr_trap.c b/sys/kern/subr_trap.c
index 7ffb9682f912..c0c0fd58de6a 100644
--- a/sys/kern/subr_trap.c
+++ b/sys/kern/subr_trap.c
@@ -247,10 +247,17 @@ ast(struct trapframe *framep)
 		mtx_unlock_spin(&sched_lock);
 	}
 	if (sflag & PS_NEEDSIGCHK) {
+		int sigs;
+
+		sigs = 0;
 		PROC_LOCK(p);
-		while ((sig = cursig(td)) != 0)
+		while ((sig = cursig(td)) != 0) {
 			postsig(sig);
+			sigs++;
+		}
 		PROC_UNLOCK(p);
+		if (p->p_flag & P_KSES && sigs)
+			thread_signal_upcall(td);
 	}
 
 	userret(td, framep, sticks);
diff --git a/sys/sys/proc.h b/sys/sys/proc.h
index 8a18d2c9cfc2..afb225d8ef83 100644
--- a/sys/sys/proc.h
+++ b/sys/sys/proc.h
@@ -915,7 +915,8 @@ void	kse_link(struct kse *ke, struct ksegrp *kg);
 void	kse_unlink(struct kse *ke);
 void	ksegrp_link(struct ksegrp *kg, struct proc *p);
 void	ksegrp_unlink(struct ksegrp *kg);
-struct thread *signal_upcall(struct proc *p, int sig);
+void	thread_signal_add(struct thread *td, int sig);
+void	thread_signal_upcall(struct thread *td);
 struct	thread *thread_alloc(void);
 void	thread_exit(void) __dead2;
 int	thread_export_context(struct thread *td);