Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S933290Ab0HEO0j (ORCPT ); Thu, 5 Aug 2010 10:26:39 -0400 Received: from mail-ey0-f174.google.com ([209.85.215.174]:54979 "EHLO mail-ey0-f174.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S933203Ab0HEO0g convert rfc822-to-8bit (ORCPT ); Thu, 5 Aug 2010 10:26:36 -0400 MIME-Version: 1.0 In-Reply-To: <4C5A98A0.4030208@kernel.org> References: <1280946126-19587-3-git-send-email-wad@chromium.org> <4C5A98A0.4030208@kernel.org> Date: Thu, 5 Aug 2010 09:26:34 -0500 Message-ID: Subject: Re: [PATCH v3 3/3] init: add support for root devices specified by partition UUID From: Will Drewry To: Tejun Heo Cc: linux-kernel@vger.kernel.org, Kay Sievers , Jens Axboe , Karel Zak , "David S. Miller" , Andrew Morton , Joe Perches , Jan Blunck , Greg Kroah-Hartman Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 8BIT Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2210 Lines: 47 On Thu, Aug 5, 2010 at 5:55 AM, Tejun Heo wrote: > Hello, > > On 08/04/2010 08:22 PM, Will Drewry wrote: >> @@ -642,6 +642,7 @@ void __init printk_all_partitions(void) >> ? ? ? ? ? ? ? struct hd_struct *part; >> ? ? ? ? ? ? ? char name_buf[BDEVNAME_SIZE]; >> ? ? ? ? ? ? ? char devt_buf[BDEVT_SIZE]; >> + ? ? ? ? ? ? u8 uuid[PARTITION_META_INFO_UUIDLTH * 2 + 1]; >> >> ? ? ? ? ? ? ? /* >> ? ? ? ? ? ? ? ?* Don't show empty devices or things that have been >> @@ -660,10 +661,14 @@ void __init printk_all_partitions(void) >> ? ? ? ? ? ? ? while ((part = disk_part_iter_next(&piter))) { >> ? ? ? ? ? ? ? ? ? ? ? bool is_part0 = part == &disk->part0; >> >> - ? ? ? ? ? ? ? ? ? ? printk("%s%s %10llu %s", is_part0 ? "" : " ?", >> + ? ? ? ? ? ? ? ? ? ? uuid[0] = 0; >> + ? ? ? ? ? ? ? ? ? ? if (part->info) >> + ? ? ? ? ? ? ? ? ? ? ? ? ? ? part_unpack_uuid(part->info->uuid, uuid); >> + >> + ? ? ? ? ? ? ? ? ? ? printk("%s%s %10llu %s %s", is_part0 ? "" : " ?", >> ? ? ? ? ? ? ? ? ? ? ? ? ? ? ?bdevt_str(part_devt(part), devt_buf), >> ? ? ? ? ? ? ? ? ? ? ? ? ? ? ?(unsigned long long)part->nr_sects >> 1, >> - ? ? ? ? ? ? ? ? ? ? ? ? ? ?disk_name(disk, part->partno, name_buf)); >> + ? ? ? ? ? ? ? ? ? ? ? ? ? ?disk_name(disk, part->partno, name_buf), uuid); > > Hmmm... I'm a bit worried about this. ?This might break userspace > tools. ?I think it would be better to export it via sysfs. Cool - I'm happy to drop that part from the patch. I was more following the spirit of the comment around making it easy for a user to figure out what went wrong (e.g., wrong uuid) if they don't have a root, but if there are tools parsing that output, I'd rather not break them! Would sysfs make sense as part of this patch series or would it be fair game for a follow-on? I'm inclined to wait since the UUIDs can't be changed (blkpg support isn't wired up) except with rescans, and a userspace tool can just walk the partition table to get the uuids. Thanks! -- 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/