From mboxrd@z Thu Jan 1 00:00:00 1970 From: Hannes Reinecke Subject: Re: complete boot failure in 4.5-rc1 caused by nvme: make SG_IO support optional Date: Mon, 8 Feb 2016 16:19:13 +0100 Message-ID: <56B8B1F1.4070605@suse.de> 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> Mime-Version: 1.0 Content-Type: text/plain; charset=windows-1252 Content-Transfer-Encoding: QUOTED-PRINTABLE Return-path: In-Reply-To: <20160208151258.GB25111@localhost.localdomain> Sender: linux-kernel-owner@vger.kernel.org To: Keith Busch , Christoph Hellwig Cc: Sagi Grimberg , James Bottomley , Jens Axboe , linux-block@vger.kernel.org, linux-scsi , "linux-nvme@lists.infradead.org" , linux-kernel List-Id: linux-scsi@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. >=20 > It's even worse. NGUID was defined for 1.2 devices and higher. 1.1 > devices should have EUI-64 at: > =20 > /sys/block/nvmeXnY/eui >=20 > 1.2 devices will have either uuid or eui (or both). >=20 > The majority of devices in circulation today are 1.0, and need to con= cat > these three entries to make a unique identifier: >=20 > /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 --=20 Dr. Hannes Reinecke Teamlead Storage & Networking hare@suse.de +49 911 74053 688 SUSE LINUX GmbH, Maxfeldstr. 5, 90409 N=FCrnberg GF: F. Imend=F6rffer, J. Smithard, J. Guild, D. Upmanyu, G. Norton HRB 21284 (AG N=FCrnberg)