From mboxrd@z Thu Jan 1 00:00:00 1970 From: Steve Wise Subject: Re: [PATCH 2.6.37] RDMA/cxgb3: When a user QP is marked in error, also mark the CQs in error. Date: Wed, 20 Oct 2010 17:36:54 -0500 Message-ID: <4CBF6F06.7030703@opengridcomputing.com> References: <20101020214432.4869.50981.stgit@build.ogc.int> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: Sender: linux-rdma-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org To: Roland Dreier Cc: linux-rdma-u79uwXL29TY76Z2rM5mHXA@public.gmane.org List-Id: linux-rdma@vger.kernel.org On 10/20/2010 04:54 PM, Roland Dreier wrote: > > - bump the ABI since the create_cq uverbs response changes. > > > - detect older libraries and reduce the mmap size accordingly. > > If you bump the ABI, will older libraries still run with the new driver? > Or will they just bail out with "unsupported ABI version"? > > Well, the existing lib versions don't look at the ABI at all. :) So we're ok. And I put logic in the driver to detect the old libs vs ABI 1 libs. > If you can work with both old and new userspace libraries, is there any > reason for an ABI break anyway? > The ABI version bump tells the new library that the kernel driver supports this new functionality. I don't know another way to do this without the ABI bump. The kernel driver detects the library ABI via the size of the create_cq response that's passed in from the lib. But in the other direction, I think the only was is with the ABI number. Steve. -- 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