Patch "vb2: V4L2_BUF_FLAG_DONE is set after DQBUF" has been added to the 4.4-stable tree

[<gregkh@linuxfoundation.org>]

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;a=summary

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