From mboxrd@z Thu Jan 1 00:00:00 1970 From: Knut Omang Subject: Re: [PATCH 5/9] ib_uverbs: Add padding to end align ib_uverbs_reg_mr_resp Date: Fri, 02 Sep 2016 09:54:43 +0200 Message-ID: <1472802883.3975.21.camel@oracle.com> References: <1472774969-18997-1-git-send-email-knut.omang@oracle.com> <1472774969-18997-6-git-send-email-knut.omang@oracle.com> <20160902020945.GB30057@obsidianresearch.com> Mime-Version: 1.0 Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: 8BIT Return-path: In-Reply-To: <20160902020945.GB30057-ePGOBjL8dl3ta4EC/59zMFaTQe2KTcn/@public.gmane.org> Sender: linux-rdma-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org To: Jason Gunthorpe Cc: Doug Ledford , linux-rdma-u79uwXL29TY76Z2rM5mHXA@public.gmane.org List-Id: linux-rdma@vger.kernel.org On Thu, 2016-09-01 at 20:09 -0600, Jason Gunthorpe wrote: > On Fri, Sep 02, 2016 at 02:09:25AM +0200, Knut Omang wrote: > > > > The ib_uverbs_reg_mr_resp structure was not 64 bit end aligned > > as required by the protocol. This causes alignment issues > > if a device specific driver needs to transfer extra response > > arguments. > Can you explain in the commit message why this doesn't break anything? > How does compat work with existing libibverbs? It doesn't, and I realize I need to handle both old userspace -> new kernel new userspace -> old kernel I am working on a fix for it, which would have to be in ib_uverbs due to the  if  ( != )     fail semantics which effectively inhibits any changes at all  :-/ 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