Subject: Re: [PATCH net-next v2 07/12] ethtool: Add MAC loopback support via ethtool_ops

From: Breno Leitao <[email-masked]>
Date: Thu, 26 Mar 2026 02:49:18 -0700

On Wed, Mar 25, 2026 at 03:50:14PM +0100, Björn Töpel wrote:

> @@ -284,20 +305,31 @@ static int loopback_dump_one_dev(struct sk_buff *skb,
>  {
>  	struct loopback_req_info *req_info =
>  		container_of(ctx->req_info, struct loopback_req_info, base);
> +	/* pos_sub encodes: upper 16 bits = component phase, lower 16 = index
> +	 * within that component. dump_one_dev is called repeatedly with
> +	 * increasing pos_sub until all components are exhausted.
> +	 */
> +	enum ethtool_loopback_component phase = *pos_sub >> 16;
> +	u32 idx = *pos_sub & 0xffff;

Consider introducing macros for these bit operations to improve code
readability. Named macros would make the shift and mask operations more
self-documenting and facilitate future changes, if we eventually get
there.