Re: [PATCH 8/8] staging: rtl8188eu: use is_broadcast_ether_addr

From: Joe Perches
Date: Sun Jul 29 2018 - 14:00:02 EST


On Sun, 2018-07-29 at 19:42 +0200, Michael Straube wrote:
> On 07/29/18 19:21, Joe Perches wrote:
> > On Sun, 2018-07-29 at 19:08 +0200, Michael Straube wrote:
> > > Use is_broadcast_ether_addr instead of checking each byte of the
> > > address array for 0xff. Shortens the code and improves readability.
> >
> > You should show in the commit log that sta_addr is __aligned(2)
> > as required by is_broadcast_ether_addr, otherwise you could be
> > introducing runtime alignment defects.
> >
>
> Ok, sta_addr is used from following structs.
>
> struct ieee_param {
> u32 cmd;
> u8 sta_addr[ETH_ALEN];
> union {
> ...
> ...
> }; u
> };
>
> struct ieee_param_ex {
> u32 cmd;
> u8 sta_addr[ETH_ALEN];
> u8 data[0];
> };
>
> Well, looking at it now, I'm not sure about the alignment anymore
> in the struct that contains the union. Is sta_addr in the first
> struct __aligned(2)?
>
> Should I include the snippets in the commit message, or is just
> writing that sta_addr is __aligned(2) enough? (if it is in the
> first case...)

It's enough to just state that the uses are properly aligned
as long as you looked and understand that it's required.