From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754643AbcBHPTU (ORCPT ); Mon, 8 Feb 2016 10:19:20 -0500 Received: from mx2.suse.de ([195.135.220.15]:46455 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754542AbcBHPTQ (ORCPT ); Mon, 8 Feb 2016 10:19:16 -0500 Subject: Re: complete boot failure in 4.5-rc1 caused by nvme: make SG_IO support optional To: Keith Busch , Christoph Hellwig References: <1454783624.2809.6.camel@HansenPartnership.com> <20160207092241.GA15331@lst.de> <1454861040.2329.4.camel@HansenPartnership.com> <56B7C527.6050300@kernel.dk> <1454886441.2329.27.camel@HansenPartnership.com> <56B8448A.3000106@suse.de> <56B8676C.20600@dev.mellanox.co.il> <20160208101350.GA32632@lst.de> <20160208151258.GB25111@localhost.localdomain> Cc: Sagi Grimberg , James Bottomley , Jens Axboe , linux-block@vger.kernel.org, linux-scsi , "linux-nvme@lists.infradead.org" , linux-kernel From: Hannes Reinecke Message-ID: <56B8B1F1.4070605@suse.de> Date: Mon, 8 Feb 2016 16:19:13 +0100 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:38.0) Gecko/20100101 Thunderbird/38.5.0 MIME-Version: 1.0 In-Reply-To: <20160208151258.GB25111@localhost.localdomain> Content-Type: text/plain; charset=windows-1252 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 02/08/2016 04:12 PM, Keith Busch wrote: > On Mon, Feb 08, 2016 at 11:13:50AM +0100, Christoph Hellwig wrote: >> On Mon, Feb 08, 2016 at 12:01:16PM +0200, Sagi Grimberg wrote: >>> >>>> Do we have defined sysfs attributes for NVMe devices nowadays? >>> >>> /sys/block/nvme0n1/uuid >> >> That's only supported for NVMe 1.1 and higher devices, and optional. >> For older or stupid devices we need to support the algorithm based >> on the serial attribute from nvme_fill_device_id_scsi_string() in >> drivers/nvme/host/scsi.c. > > It's even worse. NGUID was defined for 1.2 devices and higher. 1.1 > devices should have EUI-64 at: > > /sys/block/nvmeXnY/eui > > 1.2 devices will have either uuid or eui (or both). > > The majority of devices in circulation today are 1.0, and need to concat > these three entries to make a unique identifier: > > /sys/block/nvmeXnY/device/serial > /sys/block/nvmeXnY/device/model > /sys/block/nvmeXnY/nsid Ok, so what about having a 'wwid' attribute which provides combined information (like scsi has)? Cheers, Hannes -- Dr. Hannes Reinecke Teamlead Storage & Networking hare@suse.de +49 911 74053 688 SUSE LINUX GmbH, Maxfeldstr. 5, 90409 Nürnberg GF: F. Imendörffer, J. Smithard, J. Guild, D. Upmanyu, G. Norton HRB 21284 (AG Nürnberg)