From owner-freebsd-stable@FreeBSD.ORG Fri Nov 2 18:59:32 2012 Return-Path: Delivered-To: freebsd-stable@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [69.147.83.52]) by hub.freebsd.org (Postfix) with ESMTP id 1ECBE806 for ; Fri, 2 Nov 2012 18:59:32 +0000 (UTC) (envelope-from gpalmer@freebsd.org) Received: from noop.in-addr.com (mail.in-addr.com [IPv6:2001:470:8:162::1]) by mx1.freebsd.org (Postfix) with ESMTP id DB4DF8FC0A for ; Fri, 2 Nov 2012 18:59:31 +0000 (UTC) Received: from gjp by noop.in-addr.com with local (Exim 4.80.1 (FreeBSD)) (envelope-from ) id 1TUMSn-000DYN-Ba; Fri, 02 Nov 2012 14:59:29 -0400 Date: Fri, 2 Nov 2012 14:59:29 -0400 From: Gary Palmer To: Mateusz Guzik Subject: Re: [patch] Re: SU+J on 9.1-RC2 ISO Message-ID: <20121102185929.GA24320@in-addr.com> References: <5093F934.7050306@ose.nl> <5093FD3D.3080201@ateamsystems.com> <1351876381.2657.1.camel@mjakubik.localdomain> <50940276.5030306@ateamsystems.com> <50940C20.3090409@ose.nl> <50940E40.3090709@ose.nl> <5094112C.2070102@ose.nl> <20121102184131.GB22755@dft-labs.eu> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20121102184131.GB22755@dft-labs.eu> X-SA-Exim-Connect-IP: X-SA-Exim-Mail-From: gpalmer@freebsd.org X-SA-Exim-Scanned: No (on noop.in-addr.com); SAEximRunCond expanded to false Cc: Bas Smeelen , freebsd-stable@freebsd.org X-BeenThere: freebsd-stable@freebsd.org X-Mailman-Version: 2.1.14 Precedence: list List-Id: Production branch of FreeBSD source code List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Fri, 02 Nov 2012 18:59:32 -0000 On Fri, Nov 02, 2012 at 07:41:31PM +0100, Mateusz Guzik wrote: > On Fri, Nov 02, 2012 at 07:30:04PM +0100, Bas Smeelen wrote: > > On 11/02/2012 07:17 PM, Bas Smeelen wrote: > > > On 11/02/2012 07:08 PM, Bas Smeelen wrote: > > >> On 11/02/2012 06:27 PM, Adam Strohl wrote: > > >>> On 11/3/2012 0:13, Mike Jakubik wrote: > > >>>> You can disable SU+J after installing, though it would be nice if the > > >>>> installer gave you a choice. > > >>> This assumes that you know about this flaw, which most people do not. > > >>> > > >>> I didn't until I discovered it by panic-ing a perfectly fine running > > >>> server. Getting burned by a known bug like this shouldn't be "SOP" > > >>> for users of FreeBSD. > > >>> > > >>> If anything it should be turned off by default, and people can turn it > > >>> on if they want given the landmine it plants. If they know how to > > >>> turn it on they're much more likely to be aware of the issue. > > >>> > > >>> > > >>> > > To sum it up > > SU+J should be turned off by default because of > > 1. It does not work with dumping a live system e.g. snapshot > > 2. it is not recommended for SSD installs > > 3. "Smart" admins can turn it on if they want > > > > root@sys:/usr/src/usr.sbin/bsdinstall/partedit # diff -u gpart_ops.c > > gpart_ops.cnew > > --- gpart_ops.c 2012-08-06 01:54:33.000000000 +0200 > > +++ gpart_ops.cnew 2012-11-02 19:07:45.000000000 +0100 > > @@ -90,8 +90,8 @@ > > {"SU", "Softupdates", > > "Enable softupdates (default)", 1 }, > > {"SUJ", "Softupdates journaling", > > - "Enable file system journaling (default - " > > - "turn off for SSDs)", 1 }, > > + "Disable file system journaling (default - " > > + "turn on for adventurish admins)", 0 }, > > {"TRIM", "Enable SSD TRIM support", > > "Enable TRIM support, useful on solid-state drives", > > 0 }, > > > > Please comment, then I can file a PR or not > > As was noted in my another mail, the kernel will no longer crash when an > attempt to take a snapshot is made. Also AFAIR SUJ can be disabled > later. > > Given that I prefer the following: > > diff --git a/usr.sbin/bsdinstall/partedit/gpart_ops.c b/usr.sbin/bsdinstall/partedit/gpart_ops.c > index 479365a..80296c2 100644 > --- a/usr.sbin/bsdinstall/partedit/gpart_ops.c > +++ b/usr.sbin/bsdinstall/partedit/gpart_ops.c > @@ -91,7 +91,7 @@ newfs_command(const char *fstype, char *command, int use_default) > "Enable softupdates (default)", 1 }, > {"SUJ", "Softupdates journaling", > "Enable file system journaling (default - " > - "turn off for SSDs)", 1 }, > + "turn off for SSDs or if you use snapshots)", 1 }, > {"TRIM", "Enable SSD TRIM support", > "Enable TRIM support, useful on solid-state drives", > 0 }, > > http://people.freebsd.org/~mjg/patches/suj-snapshot-comment.diff How many people realise that snapshots are needed for dump based backups (and other related features)? Gary