[openib-general] [PATCH] IB/core - ib_umad can cause address alignment fault onia64

[Tom Tucker]

Does changing the size of the structure break the ABI?

On Thu, 2007-01-18 at 20:01 +0200, Michael S. Tsirkin wrote:
> > Quoting r. Sean Hefty <mshefty at ichips.intel.com>:
> > Subject: Re: [openib-general] [PATCH] IB/core - ib_umad can cause address alignment fault onia64
> > 
> > > But I thought it is the data field which is cast to ib_mad_hdr
> > > and not ib_user_mad? If so Jason's suggestion of using
> > > 	u64 data[0]
> > > makes more sense.
> > 
> > I don't think that you can change struct ib_user_mad or struct ib_user_mad_hdr 
> > without breaking the ABI.
> 
> This won't break ABI, since data is aligned already relative to start of struct.
> We only force the struct itself to be aligned, which has no ABI implications.
>