From mboxrd@z Thu Jan 1 00:00:00 1970 From: "Jens-U. Mozdzen" Subject: undo make-bcache (was: Re: Can't mount an encrypted backing device) Date: Mon, 13 Jan 2020 12:44:15 +0000 Message-ID: <20200113124415.Horde.G9hpYwu_fqvg2w0msexL3ri@webmail.nde.ag> References: <65c05b80-679b-2ccb-1bd1-a9a6887c9c51@suse.de> Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8; format=flowed; DelSp=Yes Return-path: Received: from gw-hh2.hh.nde.ag ([85.183.17.20]:58126 "EHLO mail.nde.ag" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726074AbgAMM4w (ORCPT ); Mon, 13 Jan 2020 07:56:52 -0500 In-Reply-To: <65c05b80-679b-2ccb-1bd1-a9a6887c9c51@suse.de> Content-Disposition: inline Sender: linux-bcache-owner@vger.kernel.org List-Id: linux-bcache@vger.kernel.org To: Coly Li Cc: linux-bcache@vger.kernel.org Hi Coly, jumping in here, because I was looking for a way to revert from bcache to plain device: Zitat von Coly Li : > The super block location of the backing disk is occupied by bcache. You > cannot mount the file system directly from the backing disk which is > formated as bcache backing device [...] (bcache offset all I/Os on > bcache device 4KB behind the requesting > LBA on backing disk). Assuming that no caching device is associated with a backing device (so the backing device is "clean" as in "containing all data blocks with the current content"), could one convert the content of a backing device to a "non-bcached device" by removing the first 4096 octets of the backing device content? Something like "dd if=backingdev of=newdev skip_bytes=4096 ..."? Regards, J