Re: [PATCH] net: qrtr: Expose tunneling endpoint to user space

[David Miller]

From: Bjorn Andersson <bjorn.andersson@xxxxxxxxxx>
Date: Wed, 18 Apr 2018 22:03:46 -0700

> +struct qrtr_tun {
> +	struct qrtr_endpoint ep;
> +
> +	struct mutex queue_lock;
> +	struct sk_buff_head queue;
> +	wait_queue_head_t readq;
> +};

The queue lock is surperfluous.  sk_buff_head and all of the helpers you
are using does it's own locking.  So you are essentially using two sets
of locks to protect the same object.