From mboxrd@z Thu Jan 1 00:00:00 1970 From: Milan Broz Subject: Re: brtfs on top of dmcrypt with SSD. No corruption iff write cache off? Date: Mon, 13 Feb 2012 00:47:54 +0100 Message-ID: <4F384FAA.5060506@redhat.com> References: <20120130003754.GD4380@merlins.org> <20120201175624.GE16796@shiny> <20120202032345.GB31903@merlins.org> <20120202124241.GW16796@shiny> <20120202152722.GI12429@merlins.org> <20120130003754.GD4380@merlins.org> <20120201175624.GE16796@shiny> <20120202032345.GB31903@merlins.org> <20120212223242.GA31989@merlins.org> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Cc: Chris Mason , linux-btrfs@vger.kernel.org, jeff@deserettechnology.com To: Marc MERLIN Return-path: In-Reply-To: <20120212223242.GA31989@merlins.org> List-ID: On 02/12/2012 11:32 PM, Marc MERLIN wrote: > Actually I had one more question. > > I read this page: > http://www.redhat.com/archives/dm-devel/2011-July/msg00042.html > > I'm not super clear if with 3.2.5 kernel, I need to pass the special > allow_discards option for brtfs and dm-crypt to be safe together, or whether > they now talk through an API and everything "just works" :) If you want discards to be supported in dmcrypt, you have to enable it manually. The most comfortable way is just use recent cryptsetup and add --allow-discards option to luksOpen command. It will be never enabled by default in dmcrypt for security reasons http://asalor.blogspot.com/2011/08/trim-dm-crypt-problems.html Milan