From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-oa0-f42.google.com ([209.85.219.42]:32781 "EHLO mail-oa0-f42.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756496Ab3GYVKY (ORCPT ); Thu, 25 Jul 2013 17:10:24 -0400 Received: by mail-oa0-f42.google.com with SMTP id j6so5707534oag.15 for ; Thu, 25 Jul 2013 14:10:24 -0700 (PDT) MIME-Version: 1.0 In-Reply-To: <20130524165947.GA2487@pyxis.br.cox.net> References: <20130524165947.GA2487@pyxis.br.cox.net> From: Bjorn Helgaas Date: Thu, 25 Jul 2013 15:10:03 -0600 Message-ID: Subject: Re: Patch: Increase maximum bus memory window size (for Xeon Phi) To: Bryce Lelbach Cc: "linux-pci@vger.kernel.org" Content-Type: text/plain; charset=ISO-8859-1 Sender: linux-pci-owner@vger.kernel.org List-ID: On Fri, May 24, 2013 at 10:59 AM, Bryce Lelbach wrote: > The attached patch affects pbus_size_mem() in drivers/pci/setup-bus.c. The patch > increases the maximum memory window size for a PCI bus from 2 Gb to 2^63 Gb. > > This change is necessary to support Intel Xeon Phi co-processors. These co-processors > are PCIe devices used for high-performance computing applications. The device requires > an 8Gb memory window to function (the co-processor has 8Gb of onboard memory). > > This patch is a modified version of a patch from Intel's MPSS framework > (specifically, from the "KNC_gold_update_1-2.1.4982-15-rhel-6.3" package), which > will apply to a 3.7.8 kernel (I am about to try it on a 3.8 kernel). To the best > of my knowledge, newer RHEL kernels are shipped with this patch. This needs a Signed-off-by before it can be applied (see Documentation/SubmittingPatches for details about what this means). Also, there's some confusion about this being in RHEL. I take it that it is not actually in RHEL, but perhaps in an Intel-supplied update that is commonly applied on top of RHEL? IIRC, a very similar patch was posted last year. It'd be nice to dig that up and credit that author as well. It's more convenient for me to receive patches as plain-text email (not attachments), also as described in SubmittingPatches. I *can* deal with attachments, but it's a hassle and I tend to keep putting them off ;) Bjorn