Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1758250AbYBPRg5 (ORCPT ); Sat, 16 Feb 2008 12:36:57 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1755749AbYBPRgs (ORCPT ); Sat, 16 Feb 2008 12:36:48 -0500 Received: from main.gmane.org ([80.91.229.2]:33588 "EHLO ciao.gmane.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755654AbYBPRgp (ORCPT ); Sat, 16 Feb 2008 12:36:45 -0500 X-Injected-Via-Gmane: http://gmane.org/ To: linux-kernel@vger.kernel.org From: Gunter Ohrner Subject: Understanding Block Device Behaviour Date: Sat, 16 Feb 2008 18:37:10 +0100 Message-ID: Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7Bit X-Complaints-To: usenet@ger.gmane.org X-Gmane-NNTP-Posting-Host: bras-co-85-197-3-127.westend.de User-Agent: KNode/0.10.5 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1705 Lines: 37 Hi! Maybe someone on this list can shed some light on my following observations. I have a machine running Linux (2.6.23 / 2.6.24) as its main OS, a Windows XP test installation on a physical primary partition and one logical drive formatted as VFAT32 for exchanging data (/dev/sda11 / "d:"). I'm running the Windows inside QEMU/KVM, using "-hda /dev/sda" to provide my physical disk to the VM. Of course, sda11 is never mounted if I start the VM. My expectation was that it should work fine to mount sda11, copy files to it, umount sda11, start the VM, and access the files from there. Short story: To my surprise this doesn't work, and I'd like to know the reason, just out of curiosity. Symptoms are that the freshly copied files do not show up in Windows in the VM and chkdsk (sometimes) reports data corruption. (Reminder: sda11 had been unmounted before starting the VM.) If I shut down the VM and mount sda11 in Linux again, the files are gone from there as well. If I mount sda11 again immediately after copying and umounting and without starting the VM in between, the files show up just fine. If I really shut of Linux and boot my Windows test installation natively, the files are also visible and working ok. I've both tried to format sda11 using mkdosfs and within Windows itself, and made sure to run chkdsk regularily to avoid suprious follow-up filesystem errors during my tests. Why doesn't it work as I expected? Greetings, Gunter -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/