From 4a567394dce57e8a2329f0a1123b951b0f070d39 Mon Sep 17 00:00:00 2001 From: "figo.zhang" Date: Sun, 17 May 2009 23:13:13 -0300 Subject: [PATCH] V4L/DVB (11852): saa7134-video.c: poll method lose race condition saa7134-video.c: poll method lose race condition Signed-off-by: Figo Zhang Signed-off-by: Mauro Carvalho Chehab --- drivers/media/video/saa7134/saa7134-video.c | 9 ++++++--- 1 file changed, 6 insertions(+), 3 deletions(-) diff --git a/drivers/media/video/saa7134/saa7134-video.c b/drivers/media/video/saa7134/saa7134-video.c index 493cad94146..ceae3c88f93 100644 --- a/drivers/media/video/saa7134/saa7134-video.c +++ b/drivers/media/video/saa7134/saa7134-video.c @@ -1423,11 +1423,13 @@ video_poll(struct file *file, struct poll_table_struct *wait) { struct saa7134_fh *fh = file->private_data; struct videobuf_buffer *buf = NULL; + unsigned int rc = 0; if (V4L2_BUF_TYPE_VBI_CAPTURE == fh->type) return videobuf_poll_stream(file, &fh->vbi, wait); if (res_check(fh,RESOURCE_VIDEO)) { + mutex_lock(&fh->cap.vb_lock); if (!list_empty(&fh->cap.stream)) buf = list_entry(fh->cap.stream.next, struct videobuf_buffer, stream); } else { @@ -1446,13 +1448,14 @@ video_poll(struct file *file, struct poll_table_struct *wait) } if (!buf) - return POLLERR; + goto err; poll_wait(file, &buf->done, wait); if (buf->state == VIDEOBUF_DONE || buf->state == VIDEOBUF_ERROR) - return POLLIN|POLLRDNORM; - return 0; + rc = POLLIN|POLLRDNORM; + mutex_unlock(&fh->cap.vb_lock); + return rc; err: mutex_unlock(&fh->cap.vb_lock); -- 2.39.2