This is a note to let you know that I've just added the patch titled
vb2: V4L2_BUF_FLAG_DONE is set after DQBUF
to the 4.4-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git%3Ba=su...
The filename of the patch is: vb2-v4l2_buf_flag_done-is-set-after-dqbuf.patch and it can be found in the queue-4.4 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree, please let stable@vger.kernel.org know about it.
From foo@baz Thu Feb 15 08:44:17 CET 2018
From: Hans Verkuil hverkuil@xs4all.nl Date: Wed, 14 Feb 2018 12:52:28 +0100 Subject: vb2: V4L2_BUF_FLAG_DONE is set after DQBUF To: stable@vger.kernel.org Cc: linux-media@vger.kernel.org, Ricardo Ribalda Delgado ricardo.ribalda@gmail.com, Hans Verkuil hans.verkuil@cisco.com, Mauro Carvalho Chehab mchehab@s-opensource.com Message-ID: 20180214115240.27650-3-hverkuil@xs4all.nl
From: Ricardo Ribalda ricardo.ribalda@gmail.com
commit 3171cc2b4eb9831ab4df1d80d0410a945b8bc84e upstream.
According to the doc, V4L2_BUF_FLAG_DONE is cleared after DQBUF:
V4L2_BUF_FLAG_DONE 0x00000004 ... After calling the VIDIOC_QBUF or VIDIOC_DQBUF it is always cleared ...
Unfortunately, it seems that videobuf2 keeps it set after DQBUF. This can be tested with vivid and dev_debug:
[257604.338082] video1: VIDIOC_DQBUF: 71:33:25.00260479 index=3, type=vid-cap, flags=0x00002004, field=none, sequence=163, memory=userptr, bytesused=460800, offset/userptr=0x344b000, length=460800
This patch forces FLAG_DONE to 0 after calling DQBUF.
Reported-by: Dimitrios Katsaros patcherwork@gmail.com Signed-off-by: Ricardo Ribalda Delgado ricardo.ribalda@gmail.com Signed-off-by: Hans Verkuil hans.verkuil@cisco.com Signed-off-by: Mauro Carvalho Chehab mchehab@s-opensource.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- drivers/media/v4l2-core/videobuf2-v4l2.c | 6 ++++++ 1 file changed, 6 insertions(+)
--- a/drivers/media/v4l2-core/videobuf2-v4l2.c +++ b/drivers/media/v4l2-core/videobuf2-v4l2.c @@ -593,6 +593,12 @@ static int vb2_internal_dqbuf(struct vb2 b->flags & V4L2_BUF_FLAG_LAST) q->last_buffer_dequeued = true;
+ /* + * After calling the VIDIOC_DQBUF V4L2_BUF_FLAG_DONE must be + * cleared. + */ + b->flags &= ~V4L2_BUF_FLAG_DONE; + return ret; }
Patches currently in stable-queue which might be from hverkuil@xs4all.nl are
queue-4.4/media-v4l2-compat-ioctl32.c-copy-m.userptr-in-put_v4l2_plane32.patch queue-4.4/media-v4l2-compat-ioctl32.c-avoid-sizeof-type.patch queue-4.4/media-v4l2-compat-ioctl32.c-drop-pr_info-for-unknown-buffer-type.patch queue-4.4/media-v4l2-compat-ioctl32.c-add-missing-vidioc_prepare_buf.patch queue-4.4/vb2-v4l2_buf_flag_done-is-set-after-dqbuf.patch queue-4.4/media-v4l2-compat-ioctl32.c-refactor-compat-ioctl32-logic.patch queue-4.4/media-v4l2-compat-ioctl32.c-fix-ctrl_is_pointer.patch queue-4.4/media-v4l2-compat-ioctl32.c-move-helper-functions-to-__get-put_v4l2_format32.patch queue-4.4/media-v4l2-compat-ioctl32.c-don-t-copy-back-the-result-for-certain-errors.patch queue-4.4/media-v4l2-compat-ioctl32.c-make-ctrl_is_pointer-work-for-subdevs.patch queue-4.4/media-v4l2-compat-ioctl32.c-fix-the-indentation.patch queue-4.4/media-v4l2-compat-ioctl32-copy-v4l2_window-global_alpha.patch queue-4.4/media-v4l2-ioctl.c-don-t-copy-back-the-result-for-enotty.patch queue-4.4/media-v4l2-compat-ioctl32.c-copy-clip-list-in-put_v4l2_window32.patch