Re: [PATCH v3 03/33] staging: rtl8192e: Mark unaligned memcpy()

Dan Carpenter
2015-05-13T08:23:11Z

On Tue, May 12, 2015 at 10:00:13PM +0200, Mateusz Kulikowski wrote:
> On 11.05.2015 10:26, Dan Carpenter wrote:
> (...)
> >> */
> >> skb_pull(sub_skb, SNAP_SIZE);
> >> - memcpy(skb_push(sub_skb, ETH_ALEN), prxb->src, ETH_ALEN);
> >> - memcpy(skb_push(sub_skb, ETH_ALEN), prxb->dst, ETH_ALEN);
> >> + memcpy(skb_push(sub_skb, ETH_ALEN), prxb->src,
> >> + ETH_ALEN); /* Must be unaligned */
> >
> >
> > Which part isn't aligned? I think they both are.
> >
> struct rtllib_rxb *prxb = prxbIndicateArray[j];
>
> struct rtllib_rxb {
> u8 nr_subframes;
> struct sk_buff *subframes[MAX_SUBFRAME_COUNT == 64];
> u8 dst[ETH_ALEN]; // here
> u8 src[ETH_ALEN]; // here
> } __packed;
>
> Either I forgot alignment / packing rules or this fields are never aligned "by design".

You must have forgotten something... Everything after the pointer is
going to be aligned sizeof(void *).

regards,
dan carpenter