diff --git a/sys/sparc64/sparc64/vm_machdep.c b/sys/sparc64/sparc64/vm_machdep.c
index 4ef0ed92530..cb21b7311c5 100644
--- a/sys/sparc64/sparc64/vm_machdep.c
+++ b/sys/sparc64/sparc64/vm_machdep.c
@@ -300,6 +300,8 @@ cpu_fork(struct thread *td1, struct proc *p2, struct thread *td2, int flags)
 	fp->fr_local[0] = (u_long)fork_return;
 	fp->fr_local[1] = (u_long)td2;
 	fp->fr_local[2] = (u_long)tf;
+	/* Terminate stack traces at this frame. */
+	fp->fr_pc = fp->fr_fp = 0;
 	pcb2->pcb_sp = (u_long)fp - SPOFF;
 	pcb2->pcb_pc = (u_long)fork_trampoline - 8;