From: Stephen Warren Subject: Re: [RFC 2/2] mmc: use SD/MMC host ID for block device name ID Date: Tue, 01 Apr 2014 14:47:36 -0600 Message-ID: <533B25E8.8040201@wwwdotorg.org> References: <2f6ac51155f9d34791b274b5102d15a997ff8b99.1396384101.git.stefan@agner.ch> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <2f6ac51155f9d34791b274b5102d15a997ff8b99.1396384101.git.stefan@agner.ch> Sender: linux-mmc-owner@vger.kernel.org To: stefan@agner.ch, chris@printf.net, linux-mmc@vger.kernel.org Cc: linux-tegra@vger.kernel.org, linux@arm.linux.org.uk, linux-kernel@vger.kernel.org List-Id: linux-tegra@vger.kernel.org On 04/01/2014 02:35 PM, stefan@agner.ch wrote: > From: Stefan Agner > > By using the SD/MMC host device ID as a starting point for block > device numbering, one can reliably predict the first block device > name (at least for the first controller). That's not true. There's no guarantee that a device name/ID gets released as soon as the SD card is removed; something might still have it mounted for example. The correct solution here is to use filesystem or partition UUIDs to identify the device/partition, not to attempt to assign static device IDs.