From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mailman by lists.gnu.org with archive (Exim 4.43) id 1K7BdH-0001IF-72 for mharc-grub-devel@gnu.org; Fri, 13 Jun 2008 11:56:07 -0400 Received: from mailman by lists.gnu.org with tmda-scanned (Exim 4.43) id 1K7BdF-0001Gn-4S for grub-devel@gnu.org; Fri, 13 Jun 2008 11:56:05 -0400 Received: from exim by lists.gnu.org with spam-scanned (Exim 4.43) id 1K7BdD-0001Er-De for grub-devel@gnu.org; Fri, 13 Jun 2008 11:56:04 -0400 Received: from [199.232.76.173] (port=57353 helo=monty-python.gnu.org) by lists.gnu.org with esmtp (Exim 4.43) id 1K7BdC-0001EO-UE for grub-devel@gnu.org; Fri, 13 Jun 2008 11:56:03 -0400 Received: from c60.cesmail.net ([216.154.195.49]:11571) by monty-python.gnu.org with esmtps (TLS-1.0:RSA_ARCFOUR_SHA1:16) (Exim 4.60) (envelope-from ) id 1K7BdC-0003bk-DR for grub-devel@gnu.org; Fri, 13 Jun 2008 11:56:02 -0400 Received: from unknown (HELO relay.cesmail.net) ([192.168.1.81]) by c60.cesmail.net with ESMTP; 13 Jun 2008 11:56:01 -0400 Received: from [192.168.0.21] (static-72-92-88-10.phlapa.fios.verizon.net [72.92.88.10]) by relay.cesmail.net (Postfix) with ESMTP id EC04E619058 for ; Fri, 13 Jun 2008 11:56:00 -0400 (EDT) From: Pavel Roskin To: The development of GRUB 2 In-Reply-To: References: Content-Type: text/plain Date: Fri, 13 Jun 2008 11:55:59 -0400 Message-Id: <1213372559.29669.14.camel@dv> Mime-Version: 1.0 X-Mailer: Evolution 2.22.2 (2.22.2-2.fc9) Content-Transfer-Encoding: 7bit X-detected-kernel: by monty-python.gnu.org: Genre and OS details not recognized. Subject: Re: Some concern about the journal support X-BeenThere: grub-devel@gnu.org X-Mailman-Version: 2.1.5 Precedence: list Reply-To: The development of GRUB 2 List-Id: The development of GRUB 2 List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Fri, 13 Jun 2008 15:56:05 -0000 On Fri, 2008-06-13 at 17:05 +0800, Bean wrote: > Hi, > > I think we need to disable journal sometimes. Tools like grub-setup > and grub-install is run in an active system, that means sectors could > easily end up in the journal. However, journal is a temperately > buffer, space can be reused after a while. In this case, we should > bypass the journal and access the underlying file system directly. > Perhaps we can use a variable like no_journal to control the journal > support, any suggestions ? If we are going to hardcode block locations somewhere, hardcoding a journal location is a serious bug. It will be overwritten. If we are just reading from a live filesystem, there is no 100% correct solution, but avoiding the journal seems safer to me. We load the mappings once, but we read from the journal when the need arises. The journal can be overwritten by background activity that the administrator doesn't control. If we ignore the journal, inconsistencies would normally arise only if any files used by grub are modified in the meantime. Those should be owned by root, and no reasonable administrator would touch them while grub-install is running. We still want journal support for testing purposes, so perhaps grub-fstest should have a switch to use the journal. -- Regards, Pavel Roskin