From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jason Gunthorpe Subject: Re: [PATCH rdma-next 0/3] Support out of order data placement Date: Mon, 12 Jun 2017 10:29:17 -0600 Message-ID: <20170612162917.GA11993@obsidianresearch.com> References: <20170612064918.12510-1-leon@kernel.org> <1497281280.2770.1.camel@wdc.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: Content-Disposition: inline In-Reply-To: Sender: linux-rdma-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org To: Parav Pandit Cc: Bart Van Assche , "leon-DgEjT+Ai2ygdnm+yROfE0A@public.gmane.org" , "dledford-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org" , "linux-rdma-u79uwXL29TY76Z2rM5mHXA@public.gmane.org" , Idan Burstein List-Id: linux-rdma@vger.kernel.org On Mon, Jun 12, 2017 at 04:19:37PM +0000, Parav Pandit wrote: > So, - to your question - shouldn't that be a flag to disable > out-of-order writes? By default, its disabled at RDMA level. Bart's point is that it is not disabled, by default, it is platform specific by default. Your patch makes makes it more likely a ULP will see out of order writes, but it is already the case that any ULP that relies on this is platform specific and/or broken. I think the answer to Bart's question is that some MPI ULPs are 'broken' and only work on x86 - setting this bit by default would cause them to stop working. It is unfortunate this is the rare case. I would suggest at least using the inverted sense like Bart describes in the kernel - every kernel ULP is safe. 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