From owner-freebsd-current@FreeBSD.ORG Wed Oct 14 13:30:45 2009 Return-Path: Delivered-To: freebsd-current@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id ACFBD106568D for ; Wed, 14 Oct 2009 13:30:45 +0000 (UTC) (envelope-from a_best01@uni-muenster.de) Received: from zivm-exrelay3.uni-muenster.de (ZIVM-EXRELAY3.UNI-MUENSTER.DE [128.176.192.20]) by mx1.freebsd.org (Postfix) with ESMTP id 41A678FC13 for ; Wed, 14 Oct 2009 13:30:44 +0000 (UTC) X-IronPort-AV: E=Sophos;i="4.44,557,1249250400"; d="scan'208";a="15848491" Received: from zivmaildisp1.uni-muenster.de (HELO ZIVMAILUSER01.UNI-MUENSTER.DE) ([128.176.188.85]) by zivm-relay3.uni-muenster.de with ESMTP; 14 Oct 2009 15:30:43 +0200 Received: by ZIVMAILUSER01.UNI-MUENSTER.DE (Postfix, from userid 149459) id 928411B0766; Wed, 14 Oct 2009 15:30:43 +0200 (CEST) Date: Wed, 14 Oct 2009 15:30:43 +0200 (CEST) From: Alexander Best Sender: Organization: Westfaelische Wilhelms-Universitaet Muenster To: Message-ID: In-Reply-To: <20091014151026.699a5765@ernst.jennejohn.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit Cc: freebsd-current@FreeBSD.org Subject: Re: buffers not syncing correctly during shutdown X-BeenThere: freebsd-current@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: Discussions about the use of FreeBSD-current List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Wed, 14 Oct 2009 13:30:45 -0000 Gary Jennejohn schrieb am 2009-10-14: > On Wed, 14 Oct 2009 12:49:54 +0200 (CEST) > Alexander Best wrote: > > hi there, > > to keep it short: > > 1. mount a removable device (e.g. an usb stick) (better use -r to > > prevent data > > loss) > > 2. unplug the device (without unmounting it) > > 3. `shutdown -r now` > > what happens is that the usual shutdown routine gets processed > > until all > > buffers are synced, but then the system stalls. > > after resetting the system all devices (which were supposed to be > > synced) are > > marked dirty and are being fsck'ed. > > cheers. > > alex > > oh...and i'm running FreeBSD otaku 9.0-CURRENT FreeBSD 9.0-CURRENT > > #0 r197914: > > Sat Oct 10 02:58:19 CEST 2009 > > root@otaku:/usr/obj/usr/src/sys/ARUNDEL > > i386 > I'm inclined to say that umount'ing the file systems is failing > because > you pulled the USB stick out without doing umount. Of course, that > results in all file systems still being marked dirty. Obviously, > this > pathological case isn't being handled. > I personally don't see why it ever should be handled. This is UNIX > not > Windows and users should be smart enough to know that they umount > such > devices before removing them otherwise nasty things can happen. > --- > Gary Jennejohn this is 2009 and not the 70s/80s. the amount or non-removable devices is declining day by day. eventually all storage devices will become removable and freebsd should keep up with this development. i don't think labelling this obvious bug as a grand unix feature is valid. also there are other scenarios where this problem can occur. if the device produces i/o errors you won't be able to unmount it even with the -f switch. alex