From mboxrd@z Thu Jan 1 00:00:00 1970 From: Christoph Hellwig Subject: Re: [BUG] remount ro on loopback mount leaves unmountable filesystem behind Date: Tue, 13 May 2008 06:23:40 -0400 Message-ID: <20080513102340.GA15112@infradead.org> References: <20080513085047.GY155679365@sgi.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: lkml , linux-fsdevel , util-linux-ng-u79uwXL29TY76Z2rM5mHXA@public.gmane.org To: David Chinner Return-path: Content-Disposition: inline In-Reply-To: <20080513085047.GY155679365-sJ/iWh9BUns@public.gmane.org> Sender: util-linux-ng-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org List-Id: linux-fsdevel.vger.kernel.org On Tue, May 13, 2008 at 06:50:47PM +1000, David Chinner wrote: > Same thing, but remounting the loop filesystem readonly > before unmounting: > > $ mount -t xfs /dev/sdb6 /mnt/scratch > $ mkdir /mnt/scratch/mnt > $ touch /mnt/scratch/img > $ mkfs.xfs -f -d file,name=/mnt/scratch/img,size=1g > $ mount -t xfs -o loop /mnt/scratch/img /mnt/scratch/mnt > $ mount -t xfs -o remount,ro /mnt/scratch/img /mnt/scratch/mnt > $ umount /mnt/scratch/mnt > $ umount /mnt/scratch > umount: /mnt/scratch: device is busy > umount: /mnt/scratch: device is busy This is a problem in mount, no the kernel. Before the remount the /etc mtab looks something like this: /qemu/test.img /mnt xfs rw,loop=/dev/loop0 0 0 and after it looks something like this: /qemu/test.img /mnt xfs ro 0 0 As a workaround do a losetup -d /dev/loop0 after unmounting the filesystem. -- To unsubscribe from this list: send the line "unsubscribe util-linux-ng" in the body of a message to majordomo-u79uwXL29TY76Z2rM5mHXA@public.gmane.org More majordomo info at http://vger.kernel.org/majordomo-info.html