From mboxrd@z Thu Jan 1 00:00:00 1970 From: Gunter Ohrner Subject: Surprising Block Device Behaviour Date: Tue, 19 Feb 2008 20:58:18 +0100 Message-ID: Mime-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 Content-Transfer-Encoding: QUOTED-PRINTABLE To: linux-fsdevel@vger.kernel.org Return-path: Received: from main.gmane.org ([80.91.229.2]:32771 "EHLO ciao.gmane.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752205AbYBSUZI (ORCPT ); Tue, 19 Feb 2008 15:25:08 -0500 Received: from root by ciao.gmane.org with local (Exim 4.43) id 1JRZ1S-000615-4K for linux-fsdevel@vger.kernel.org; Tue, 19 Feb 2008 20:25:02 +0000 Received: from e179255192.adsl.alicedsl.de ([85.179.255.192]) by main.gmane.org with esmtp (Gmexim 0.1 (Debian)) id 1AlnuQ-0007hv-00 for ; Tue, 19 Feb 2008 20:25:02 +0000 Received: from G.Ohrner by e179255192.adsl.alicedsl.de with local (Gmexim 0.1 (Debian)) id 1AlnuQ-0007hv-00 for ; Tue, 19 Feb 2008 20:25:02 +0000 Sender: linux-fsdevel-owner@vger.kernel.org List-ID: Hi! Maybe someone on this list can shed some light on my following observat= ions. I have a machine running Linux (2.6.23 / 2.6.24) as its main OS, a Wind= ows XP test installation on a physical primary partition and one logical dr= ive formatted as VFAT32 for exchanging data (/dev/sda11 / "d:"). I'm running the Windows inside QEMU/KVM, using "-hda /dev/sda" to provi= de my physical disk to the VM. Of course, sda11 is never mounted if I start t= he 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 gon= e from there as well. If I mount sda11 again immediately after copying and umounting and with= out starting the VM in between, the files show up just fine. If I really sh= ut 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 filesyst= em errors during my tests. Why doesn't it work as I expected? Greetings, =A0 Gunter - To unsubscribe from this list: send the line "unsubscribe linux-fsdevel= " in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html