From mboxrd@z Thu Jan 1 00:00:00 1970 From: Matan Barak Subject: Re: [PATCH ib-next 2/3] IB/core: IB/core: Allow legacy verbs through extended interfaces Date: Mon, 9 Nov 2015 18:29:38 +0200 Message-ID: References: <1446745208-17733-1-git-send-email-eli@mellanox.com> <1446745208-17733-3-git-send-email-eli@mellanox.com> <20151109155539.GA116821@x-vnc01.mtx.labs.mlnx> <20151109162513.GB116821@x-vnc01.mtx.labs.mlnx> Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Return-path: In-Reply-To: <20151109162513.GB116821-lgQlq6cFzJSjLWYaRI30zHI+JuX82XLG@public.gmane.org> Sender: linux-rdma-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org To: Eli Cohen Cc: Doug Ledford , Jason Gunthorpe , Yann Droneaud , linux-rdma , Or Gerlitz , Eran Ben Elisha , matanbe-VPRAkNaXOzVWk0Htik3J/w@public.gmane.org List-Id: linux-rdma@vger.kernel.org On Mon, Nov 9, 2015 at 6:25 PM, Eli Cohen wrote: > On Mon, Nov 09, 2015 at 06:11:49PM +0200, Matan Barak wrote: >> > >> > Like Haggai mentioned in the other response, checkpatch issues error >> > on this claiming that ENOSYS is reserved to unavailable system calls. >> > Is it applicable only for new implementations I am not sure. I don't >> > have clear preference for either ENOSYS or EINAVL. >> >> I think it could break old applications: >> err = extended_verb(the_first_extension_we_added); >> if (err == ENOSYS) >> err = legacy_verb(); >> if (err) >> return err; > > Can you send a pointer to the code where this could happen? > This is a hypothetical application code that could break. >> >> Such applications used the first extension (that was added during the >> addition of the extended verb) and when they realized it's not >> supported, they dropped to the legacy verb. This change can now cause >> the return of -EINVAL an early termination with an error. >> -- 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