From owner-freebsd-stable@FreeBSD.ORG Fri Nov 2 18:31:34 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 C1623D57 for ; Fri, 2 Nov 2012 18:31:34 +0000 (UTC) (envelope-from mjguzik@gmail.com) Received: from mail-we0-f182.google.com (mail-we0-f182.google.com [74.125.82.182]) by mx1.freebsd.org (Postfix) with ESMTP id 450A98FC08 for ; Fri, 2 Nov 2012 18:31:33 +0000 (UTC) Received: by mail-we0-f182.google.com with SMTP id x43so2149191wey.13 for ; Fri, 02 Nov 2012 11:31:33 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20120113; h=date:from:to:cc:subject:message-id:references:mime-version :content-type:content-disposition:in-reply-to:user-agent; bh=BnIuo/D/Buht6H0f7kXkZznLxWcIEVDwGTtu27oEH+c=; b=y8rdqmuj9x8XbfGPvtBlTqD8I626waqV8aWiy2IpIBB0nfpfI9gH3GeFBSlmFogG7r BezNg9isp8agkVRzcLTN6j/6MtbgTsYbo/CNFfY6tULEA8TNlRrIV2Rhh6uVWRx8Qnv2 Ux4P4MwXvUwa9rgqkgwQt/dF0fQPaaV4mw3YMsoCkScFCFqGgoNZMiuDBWeCBLOJEvB0 BLWEVze/xdX5M85zagpbeZPJH3XjBFQauSvL5Lo1K5V88YX++MabGpXEMqVF7g2c15S1 Uot4E4xkzoV1AU/doQT31b6525RgZ6e7JpWTqnZiP/xno+JMMoy+W8JdbS//GdimzUWb OTog== Received: by 10.180.7.197 with SMTP id l5mr3970781wia.13.1351881092865; Fri, 02 Nov 2012 11:31:32 -0700 (PDT) Received: from dft-labs.eu (n1x0n-1-pt.tunnel.tserv5.lon1.ipv6.he.net. [2001:470:1f08:1f7::2]) by mx.google.com with ESMTPS id dt9sm3345227wib.1.2012.11.02.11.31.31 (version=TLSv1/SSLv3 cipher=OTHER); Fri, 02 Nov 2012 11:31:32 -0700 (PDT) Date: Fri, 2 Nov 2012 19:31:24 +0100 From: Mateusz Guzik To: Adam Strohl Subject: Re: SU+J on 9.1-RC2 ISO Message-ID: <20121102183123.GA22755@dft-labs.eu> References: <5093F934.7050306@ose.nl> <5093FD3D.3080201@ateamsystems.com> <1351876381.2657.1.camel@mjakubik.localdomain> <50940276.5030306@ateamsystems.com> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: <50940276.5030306@ateamsystems.com> User-Agent: Mutt/1.5.20 (2009-06-14) Cc: Bas Smeelen , Mike Jakubik , 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 18:31:34 -0000 On Sat, Nov 03, 2012 at 12:27:18AM +0700, 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. > Currently when you try to take a snapshot, the kernel checks whether SUJ is enabled on specified mount-point, and if yes it returns EOPNOTSUPP. See this commit (MFCed as r230725): http://svnweb.freebsd.org/base?view=revision&revision=230250 So it's not that bad. > 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. > That being said, sure, you may run into another bugs, but if SUJ was enabled by default I guess it was felt that it works well enough (and in case of known bugs like problems with snapshots just bails out early). -- Mateusz Guzik