Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753804Ab0APPvn (ORCPT ); Sat, 16 Jan 2010 10:51:43 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1753403Ab0APPvm (ORCPT ); Sat, 16 Jan 2010 10:51:42 -0500 Received: from mail-bw0-f227.google.com ([209.85.218.227]:48226 "EHLO mail-bw0-f227.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750978Ab0APPvl convert rfc822-to-8bit (ORCPT ); Sat, 16 Jan 2010 10:51:41 -0500 MIME-Version: 1.0 In-Reply-To: <20100115205722.3580b6bf@lxorguk.ukuu.org.uk> References: <1263505677.2074.2.camel@yio.site> <20100115065638.005ac690@infradead.org> <20100115180341.GA12146@kroah.com> <20100115205722.3580b6bf@lxorguk.ukuu.org.uk> From: Kay Sievers Date: Sat, 16 Jan 2010 16:51:23 +0100 Message-ID: Subject: Re: Driver-Core: devtmpfs - remove EXPERIMENTAL and enable it by default To: Alan Cox Cc: Greg KH , Arjan van de Ven , linux-kernel Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8BIT Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, Jan 15, 2010 at 21:57, Alan Cox wrote: >> Why?  All major distros need this at boot time, and as we have been > > No they don't. > > Centos doesn't (in fact I suspect it'll break) > Fedora 11 doesn't > Fedora 12 doesn't seem to (but seems to be willing to use it) > Ditto all the older SuSE, Ubuntu etc releases that are *still* > active/supported/maintained Fedora, SUSE, Ubuntu, ... All releases currently in development enable and use it. >> through a release cycle with the config option, anyone who is >> incrementally updating will continue with their existing value.  But new >> people coming in, will get the option as it is most likely required to >> boot properly. >> >> Makes sense to me. > > That may well be true - in which case it needs to be very clearly > documented when to enable it. For now, the systems will bootup fine without it, but I expect over time, it will get a requirement. Udev does not care about it, but the boot scripts/initramfs tools will probably get trimmed down, because there is much less to do with the kernel provided nodes, than what is needed today to bootstrap /dev. And it should not harm any old system if it is enabled. If initramfs is used it's completely invisible, if a custom kernel with kernel-mounted rootfs is used, the udev boot script usually over-mounts the devtmpfs at /dev with an empty tmpfs, like it has always done it before. The only thing it should change is that we now should be able to bootup a box without an initramfs, without manually filling /dev with static nodes beforehand. Current distro installations do not put a single file in /dev on the rootfs, and trying to boot a kernel without an initramfs usually just fails without putting some nodes there in preparation. Thanks, Kay -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/