diff --git a/include/glibtop/proclist.h b/include/glibtop/proclist.h
index d7c859b9..ed973fdd 100644
--- a/include/glibtop/proclist.h
+++ b/include/glibtop/proclist.h
@@ -44,6 +44,8 @@ __BEGIN_DECLS
 #define GLIBTOP_KERN_PROC_UID		5
 #define GLIBTOP_KERN_PROC_RUID		6
 
+#define GLIBTOP_KERN_PROC_MASK		15
+
 #define GLIBTOP_EXCLUDE_IDLE		0x1000
 #define GLIBTOP_EXCLUDE_SYSTEM		0x2000
 #define GLIBTOP_EXCLUDE_NOTTY		0x4000
diff --git a/sysdeps/freebsd/proclist.c b/sysdeps/freebsd/proclist.c
index 68d6f870..1787a603 100644
--- a/sysdeps/freebsd/proclist.c
+++ b/sysdeps/freebsd/proclist.c
@@ -71,6 +71,8 @@ glibtop_get_proclist_p (glibtop *server, glibtop_proclist *buf,
 
 	glibtop_suid_enter (server);
 
+	which &= GLIBTOP_KERN_PROC_MASK;
+
 	/* Get the process data */
 	pinfo = kvm_getprocs (server->machine.kd, which, arg, &count);
 	if ((pinfo == NULL) || (count < 1))