Re: [PATCH libibverbs 2/3] Add padding to get proper end alignment of ibv_reg_mr_resp

[Knut Omang <knut.omang-QHcLZuEGTsvQT0dZR+AlfA@public.gmane.org>]

On Thu, 2016-09-01 at 10:42 -0600, Jason Gunthorpe wrote:
> On Thu, Sep 01, 2016 at 08:59:52AM +0200, Knut Omang wrote:
> > The user/kernel level API requires all parameter blocks to be
> > 64 bit end aligned.
> > 
> > Also clean up some valgrind/memory initialization issues.
> > 
> > Signed-off-by: Knut Omang <knut.omang-QHcLZuEGTsvQT0dZR+AlfA@public.gmane.org>
> > Reviewed-by: Mukesh Kacker <mukesh.kacker-QHcLZuEGTsvQT0dZR+AlfA@public.gmane.org>
> >  include/infiniband/kern-abi.h | 1 +
> >  src/cmd.c                     | 5 ++++-
> >  2 files changed, 5 insertions(+), 1 deletion(-)
> > 
> > diff --git a/include/infiniband/kern-abi.h b/include/infiniband/kern-abi.h
> > index f70fa44..8bdeef5 100644
> > +++ b/include/infiniband/kern-abi.h
> > @@ -367,6 +367,7 @@ struct ibv_reg_mr_resp {
> >  	__u32 mr_handle;
> >  	__u32 lkey;
> >  	__u32 rkey;
> > +	__u32 reserved;
> >  };
> 
> This structure is a copy of include/uapi/rdma/ib_user_verbs.h, so you
> need to start with a kernel patch proposing this change.

Yes, I am aware of that, sorry - I intended to post both sets in sequence but ran into 
a few recently introduced conflicts in the kernel set, so still working on that 
(just testing remains)

> We will eventually get rid of kern-abi.h and use ib_user_verbs.h at some
> point.

Good to get a common file for it and get rid of some copy/paste.

> Maybe elaborate on why this is OK and doesn't break anything in that
> patch..
> 
> > -	(void) VALGRIND_MAKE_MEM_DEFINED(resp, sizeof *resp);
> > +	(void) VALGRIND_MAKE_MEM_DEFINED(resp, resp_size);
> 
> Why the (void)?

I guess it is there to avoid compiler warnings about unused variables in some 
configuration. I just kept it as it was in this patch. I see all instances 
throughout the code has this.

Thanks,
Knut

> Jason
--
To unsubscribe from this list: send the line "unsubscribe linux-rdma" in
the body of a message to majordomo-u79uwXL29TY76Z2rM5mHXA@public.gmane.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html