Re: qcow2 corruption?

Anthony Liguori
2009-01-08T20:33:37Z

John Morrissey wrote:
> I'm encountering what seems like disk corruption when using qcow2 images,
> created with 'kvm-img create -f qcow2 image.qcow2 15G'.
>
> A simple test case is to use the Debian installer (I'm using the lenny rc1
> images from http://www.debian.org/devel/debian-installer/) to install a new
> domain. The qcow2 file on disk grows due to the mkfs(8) activity, then the
> installer faults while trying to mount the root filesystem (Invalid
> argument). 'fdisk -l' shows that the partition table just created by the
> installer is gone.
>
> In a few cases, I've managed to finish an installation, but the resulting
> filesystem is strangely corrupt:
>
> # file /usr/bin/w.procps
> /usr/bin/w.procps: gzip compressed data, was "aptitude.8", from Unix, last modified: Wed Mar 14 14:11:18 2007, max compression
>
> I've tried with the Debian packaging of KVM 79 and 82; both exhibit the same
> behavior (disclaimer: Debian has about a dozen patches in their kvm
> packaging, but they all seem to be changes to the build/install process or
> security-related). Host running KVM is up-to-date Debian lenny
> (64-bit/amd64) running kernel 2.6.26 (Debian linux-image-2.6.26-1-amd64
> 2.6.26-12).
>

There are patches that touch the block layer. Please try to reproduce
on vanilla kvm. I don't trust the debian patches.

Regards,

Anthony Liguori

> john
>