diff --git a/ipc/sem.c b/ipc/sem.c
index e20658d..cd6a733 100644
--- a/ipc/sem.c
+++ b/ipc/sem.c
@@ -2103,6 +2103,14 @@
 	struct sem_array *sma = it;
 	time_t sem_otime;
 
+	/*
+	 * The proc interface isn't aware of sem_lock(), it calls
+	 * ipc_lock_object() directly (in sysvipc_find_ipc).
+	 * In order to stay compatible with sem_lock(), we must wait until
+	 * all simple semop() calls have left their critical regions.
+	 */
+	sem_wait_array(sma);
+
 	sem_otime = get_semotime(sma);
 
 	return seq_printf(s,