From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jason Gunthorpe Subject: Re: [PATCH 6/9] ib_uverbs: Avoid vendor specific masking of attributes in query_qp Date: Fri, 2 Sep 2016 11:10:08 -0600 Message-ID: <20160902171008.GE24997@obsidianresearch.com> References: <1472774969-18997-1-git-send-email-knut.omang@oracle.com> <1472774969-18997-7-git-send-email-knut.omang@oracle.com> <20160902021300.GC30057@obsidianresearch.com> <1472791552.9410.258.camel@oracle.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: Content-Disposition: inline In-Reply-To: <1472791552.9410.258.camel-QHcLZuEGTsvQT0dZR+AlfA@public.gmane.org> Sender: linux-rdma-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org To: Knut Omang Cc: Doug Ledford , linux-rdma-u79uwXL29TY76Z2rM5mHXA@public.gmane.org List-Id: linux-rdma@vger.kernel.org On Fri, Sep 02, 2016 at 06:45:52AM +0200, Knut Omang wrote: > On Thu, 2016-09-01 at 20:13 -0600, Jason Gunthorpe wrote: > > On Fri, Sep 02, 2016 at 02:09:26AM +0200, Knut Omang wrote: > > > This commit removes the implementation and use of the modify_qp_mask > > > helper function from the generic OFED implementation and into individual > > > device drivers. > > > > > > Like with use of the ib_modify_qp_is_ok function it should be up to > > > each device driver how to handle bits set in the attribute masks. > > > > > > With the modify_qp_mask function applied in the generic code, > > > drivers would not see the bits that the user process actually sets. > > > > > > The restrictions imposed by the filter are also beyond what > > > is imposed by the Infiniband standard, and would also limit > > > future drivers or hardware from checking for unsupported or > > > invalid settings. > > > > I'm not excited about this direction. It is not OK for different > > drivers to use different mask algorithms, they must all behave the > > same. > > The problem I am solving here is that SIF expects (and requires) some of > the bits that the user correctly sets, but that Mellanox either ignore or need to > be 0. So when that mask is applied to the user input, the value that reaches > the SIF driver is not correct from SIFs perspective. > If the values goes through as the ULP sets them, then all is fine. I guess I still don't understand. SIF and mlx cannot have different behavior here. How is the application writer to know what to do? Can you give a concrete example of the problem? 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