From 39c96a1b96a5991b1c9e79b85a8d74ef93b36026 Mon Sep 17 00:00:00 2001 From: Davidlohr Bueso Date: Fri, 17 Nov 2017 15:31:11 -0800 Subject: [PATCH] sysvipc: duplicate lock comments wrt ipc_addid() The comment in msgqueues when using ipc_addid() is quite useful imo. Duplicate it for shm and semaphores. Link: http://lkml.kernel.org/r/20170831172049.14576-3-dave@stgolabs.net Signed-off-by: Davidlohr Bueso Cc: Manfred Spraul Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- ipc/sem.c | 1 + ipc/shm.c | 1 + 2 files changed, 2 insertions(+) diff --git a/ipc/sem.c b/ipc/sem.c index b2698eb..28a5c9f 100644 --- a/ipc/sem.c +++ b/ipc/sem.c @@ -515,6 +515,7 @@ static int newary(struct ipc_namespace *ns, struct ipc_params *params) sma->sem_nsems = nsems; sma->sem_ctime = ktime_get_real_seconds(); + /* ipc_addid() locks sma upon success. */ retval = ipc_addid(&sem_ids(ns), &sma->sem_perm, ns->sc_semmni); if (retval < 0) { call_rcu(&sma->sem_perm.rcu, sem_rcu_free); diff --git a/ipc/shm.c b/ipc/shm.c index bd65275..378c929 100644 --- a/ipc/shm.c +++ b/ipc/shm.c @@ -601,6 +601,7 @@ static int newseg(struct ipc_namespace *ns, struct ipc_params *params) shp->shm_file = file; shp->shm_creator = current; + /* ipc_addid() locks shp upon success. */ error = ipc_addid(&shm_ids(ns), &shp->shm_perm, ns->shm_ctlmni); if (error < 0) goto no_id; -- 2.7.4