Re: [Qemu-devel] [PATCH] qcow2: Fix refcount block allocation during qcow2_allocate_cluster_at()

[Marcelo Tosatti]

On Sun, Apr 22, 2012 at 08:18:49PM -0300, Marcelo Tosatti wrote:
> On Fri, Apr 20, 2012 at 03:56:01PM +0200, Kevin Wolf wrote:
> > Refcount block allocation and refcount table growth rely on
> > s->free_cluster_index pointing to somewhere after the current
> > allocation. Change qcow2_allocate_cluster_at() to fulfill this
> > assumption.
> > 
> > Without this change it could happen that a newly allocated refcount
> > block and the allocated data block point to the same area in the image
> > file, causing data corruption in the long run.
> > 
> > This fixes a bug that became first visible after commit 250196f1.
> > 
> > Signed-off-by: Kevin Wolf <address@hidden>
> 
> Kevin,
> 
> This patch fixes explicit filesystem errors (qemu-img check also OK), 
> but autotest is still failing, see attached screenshot. It is not
> reproducible without
> 
> f081987ad20a8c8dc391deded55161ea8d38be5f

Sorry, i meant

commit 250196f19c6e7df12965d74a5073e10aba06c802
Author: Kevin Wolf <address@hidden>
Date:   Fri Mar 2 14:10:54 2012 +0100

    qcow2: Reduce number of I/O requests