diff options
| -rw-r--r-- | fs/pipe.c | 3 | ||||
| -rw-r--r-- | kernel/watch_queue.c | 2 |
2 files changed, 3 insertions, 2 deletions
diff --git a/fs/pipe.c b/fs/pipe.c index 4eb88bc138bb..2667db9506e2 100644 --- a/fs/pipe.c +++ b/fs/pipe.c @@ -253,7 +253,8 @@ pipe_read(struct kiocb *iocb, struct iov_iter *to) */ was_full = pipe_full(pipe->head, pipe->tail, pipe->max_usage); for (;;) { - unsigned int head = pipe->head; + /* Read ->head with a barrier vs post_one_notification() */ + unsigned int head = smp_load_acquire(&pipe->head); unsigned int tail = pipe->tail; unsigned int mask = pipe->ring_size - 1; diff --git a/kernel/watch_queue.c b/kernel/watch_queue.c index c12267ccc70e..37bcd900fd77 100644 --- a/kernel/watch_queue.c +++ b/kernel/watch_queue.c @@ -113,7 +113,7 @@ static bool post_one_notification(struct watch_queue *wqueue, buf->offset = offset; buf->len = len; buf->flags = PIPE_BUF_FLAG_WHOLE; - pipe->head = head + 1; + smp_store_release(&pipe->head, head + 1); /* vs pipe_read() */ if (!test_and_clear_bit(note, wqueue->notes_bitmap)) { spin_unlock_irq(&pipe->rd_wait.lock); |