Dynamic static allocation is evil, as Kernel stack is too low, and compilation complains about it on some archs: drivers/media/v4l2-core/v4l2-async.c:238:1: warning: 'v4l2_async_notifier_unregister' uses dynamic stack allocation [enabled by default] Instead, let's enforce a limit for the buffer. In this specific case, there's a hard limit imposed by V4L2_MAX_SUBDEVS, with is currently 128. That means that the buffer size can be up to 128x8 = 1024 bytes (on a 64bits kernel), with is too big for stack. Worse than that, someone could increase it and cause real troubles. So, let's use dynamically allocated data, instead. Signed-off-by: Mauro Carvalho Chehab <m.chehab@xxxxxxxxxxx> Cc: Guennadi Liakhovetski <g.liakhovetski@xxxxxx> --- drivers/media/v4l2-core/v4l2-async.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) diff --git a/drivers/media/v4l2-core/v4l2-async.c b/drivers/media/v4l2-core/v4l2-async.c index c85d69da35bd..071596869036 100644 --- a/drivers/media/v4l2-core/v4l2-async.c +++ b/drivers/media/v4l2-core/v4l2-async.c @@ -189,12 +189,14 @@ void v4l2_async_notifier_unregister(struct v4l2_async_notifier *notifier) struct v4l2_subdev *sd, *tmp; unsigned int notif_n_subdev = notifier->num_subdevs; unsigned int n_subdev = min(notif_n_subdev, V4L2_MAX_SUBDEVS); - struct device *dev[n_subdev]; + struct device **dev; int i = 0; if (!notifier->v4l2_dev) return; + dev = kmalloc(sizeof(*dev) * n_subdev, GFP_KERNEL); + mutex_lock(&list_lock); list_del(¬ifier->list); @@ -228,6 +230,7 @@ void v4l2_async_notifier_unregister(struct v4l2_async_notifier *notifier) } put_device(d); } + kfree(dev); notifier->v4l2_dev = NULL; -- 1.8.3.1 -- To unsubscribe from this list: send the line "unsubscribe linux-media" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
