diff --git a/sys/kern/subr_smp.c b/sys/kern/subr_smp.c
index 7e85d25cbab..9ae63810f72 100644
--- a/sys/kern/subr_smp.c
+++ b/sys/kern/subr_smp.c
@@ -476,7 +476,7 @@ smp_topo_none(void)
 	top = &group[0];
 	top->cg_parent = NULL;
 	top->cg_child = NULL;
-	top->cg_mask = ~0U >> (32 - mp_ncpus);
+	top->cg_mask = all_cpus;
 	top->cg_count = mp_ncpus;
 	top->cg_children = 0;
 	top->cg_level = CG_SHARE_NONE;