Re: [PATCH] usbnet: smsc95xx: simplify tx_fixup code

[Ben Dooks]

On 2018-10-05 22:24, David Miller wrote:
> From: Ben Dooks <ben.dooks@xxxxxxxxxxxxxxx>
> Date: Tue,  2 Oct 2018 17:56:02 +0100
>
> > -	memcpy(skb->data, &tx_cmd_a, 4);
> > +	ptr = skb_push(skb, 8);
> > +	tx_cmd_a = cpu_to_le32(tx_cmd_a);
> > +	tx_cmd_b = cpu_to_le32(tx_cmd_b);
> > +	memcpy(ptr, &tx_cmd_a, 4);
> > +	memcpy(ptr+4, &tx_cmd_b, 4);
>
> Even a memcpy() through a void pointer does not guarantee that gcc will
> not emit word sized loads and stores.
>
> You must use the get_unaligned()/put_unaligned() facilities to do this
> properly.

Thanks, got a new version of the series just being tested with this.
Should it go into the original, or as a separate change?

> I also agree that making a proper type and structure instead of using
> a void pointer would be better.