From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mailgw-02.dd24.net ([193.46.215.43]:36919 "EHLO mailgw-02.dd24.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750859AbdFUMuN (ORCPT ); Wed, 21 Jun 2017 08:50:13 -0400 Message-ID: <1498049001.6359.4.camel@scientia.net> Subject: Re: Exactly what is wrong with RAID5/6 From: Christoph Anton Mitterer To: Qu Wenruo , linux-btrfs@vger.kernel.org Date: Wed, 21 Jun 2017 14:43:21 +0200 In-Reply-To: <60421001-5d74-2fb4-d916-7a397f246f20@cn.fujitsu.com> References: <1f5a4702-d264-51c6-aadd-d2cf521a45eb@dirtcellar.net> <60421001-5d74-2fb4-d916-7a397f246f20@cn.fujitsu.com> Content-Type: multipart/signed; micalg="sha-512"; protocol="application/x-pkcs7-signature"; boundary="=-P9rV48Pfdkuq5PHGkHBK" Mime-Version: 1.0 Sender: linux-btrfs-owner@vger.kernel.org List-ID: --=-P9rV48Pfdkuq5PHGkHBK Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable On Wed, 2017-06-21 at 16:45 +0800, Qu Wenruo wrote: > Btrfs is always using device ID to build up its device mapping. > And for any multi-device implementation (LVM,mdadam) it's never a > good=C2=A0 > idea to use device path. Isn't it rather the other way round? Using the ID is bad? Don't you remember our discussion about using leaked UUIDs (or accidental collisions) for all kinds of attacks? 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