From mboxrd@z Thu Jan 1 00:00:00 1970 From: Stephen Hemminger Subject: PCI domain size Date: Wed, 24 May 2017 16:40:08 -0700 Message-ID: <20170524164008.4d4e8e7b@xeon-e3> Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit To: dev@dpdk.org Return-path: Received: from mail-pf0-f178.google.com (mail-pf0-f178.google.com [209.85.192.178]) by dpdk.org (Postfix) with ESMTP id E6B999135 for ; Thu, 25 May 2017 01:40:16 +0200 (CEST) Received: by mail-pf0-f178.google.com with SMTP id e193so149738687pfh.0 for ; Wed, 24 May 2017 16:40:16 -0700 (PDT) Received: from xeon-e3 (76-14-207-240.or.wavecable.com. [76.14.207.240]) by smtp.gmail.com with ESMTPSA id h62sm10228995pfj.0.2017.05.24.16.40.15 for (version=TLS1_2 cipher=ECDHE-RSA-CHACHA20-POLY1305 bits=256/256); Wed, 24 May 2017 16:40:15 -0700 (PDT) List-Id: DPDK patches and discussions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: dev-bounces@dpdk.org Sender: "dev" While working on SR-IOV support on Azure, it was discovered that some applications and drivers do not support full size PCI domains. On Azure environment the PCI pass through device has a synthetic domain value (ie generated by host) which is > 16 bits. The common PCI utilities (pci-utils) and Linux kernel both support full 32 bits but DPDK does not. FreeBSD also supports 32 bit domains. Changing the one place in DPDK (rte_pci.h) in source is trivial but of course it is a major ABI breakage which is a complete flag day. I.e no binary compatiabilty is possible.