RE: [PATCH v3 net-next] net: mana: Add a driver for Microsoft Azure Network Adapter (MANA)

[Dexuan Cui]

> From: David Miller <davem@xxxxxxxxxxxxx>
> Sent: Thursday, April 8, 2021 5:41 PM
> > ...
> > In the driver code, all the structs/unions marked by __packed are used to
> > talk with the hardware, so I think __packed is necessary here?
> 
> It actually isan't in many cases, check with and without the __packed directive
> and see if anything chasnges.

Will do.

> > Do you think if it's better if we remove all the __packed, and add
> > static_assert(sizeof(struct XXX) == YYY) instead? e.g.
> >
> > @@ -105,7 +105,8 @@ struct gdma_msg_hdr {
> >         u16 msg_version;
> >         u16 hwc_msg_id;
> >         u32 msg_size;
> > -} __packed;
> > +};
> > +static_assert(sizeof(struct gdma_msg_hdr) == 16);
> 
> This won't make sure the structure member offsets are what you expect.
> 
> I think you'll have to go through the structures one-by-one by hand to
> figure out which ones really require the __packed attribute and which do not.

Got it. Let me see if I can remove all the __packed.