media: videobuf2-core: check for q->error in vb2_core_qbuf()

The vb2_core_qbuf() function didn't check if q->error was set. It is
checked in __buf_prepare(), but that function isn't called if the buffer
was already prepared before with VIDIOC_PREPARE_BUF.

So check it at the start of vb2_core_qbuf() as well.
Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Acked-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>

drivers/media/common/videobuf2/videobuf2-core.c

@@ -1377,6 +1377,11 @@ int vb2_core_qbuf(struct vb2_queue *q, unsigned int index, void *pb)
 	struct vb2_buffer *vb;
 	int ret;
 
+	if (q->error) {
+		dprintk(1, "fatal error occurred on queue\n");
+		return -EIO;
+	}
+
 	vb = q->bufs[index];
 
 	switch (vb->state) {