Re: [Qemu-devel] [PATCH 1/2] qcow2: Repair OFLAG_COPIED when fixing leaks

[Eric Blake]

On 04/28/2018 11:34 AM, Max Reitz wrote:
> Repairing OFLAG_COPIED is usually safe because it is done after the
> refcounts have been repaired.  Therefore, it we did not find anyone else
> referencing a data or L2 cluster, it makes no sense to not set
> OFLAG_COPIED -- and the other direction (clearing OFLAG_COPIED) is
> always safe, anyway, it may just induce leaks.
>
> Furthermore, if OFLAG_COPIED is actually consistent with a wrong (leaky)
> refcount, we will decrement the refcount with -r leaks, but OFLAG_COPIED
> will then be wrong.  qemu-img check should not produce images that are
> more corrupted afterwards then they were before.
>
> Buglink: https://bugzilla.redhat.com/show_bug.cgi?id=1527085
> Signed-off-by: Max Reitz <address@hidden>
> ---
>   block/qcow2-refcount.c | 25 +++++++++++++++++--------
>   1 file changed, 17 insertions(+), 8 deletions(-)

Reviewed-by: Eric Blake <address@hidden>

--
Eric Blake, Principal Software Engineer
Red Hat, Inc.           +1-919-301-3266
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