Re: [Qemu-devel] [PATCH 2/3] qcow2: Free allocated clusters on write error

[Eric Blake <eblake@redhat.com>]

On 06/28/2018 10:49 AM, Eric Blake wrote:
> On 06/28/2018 10:39 AM, Kevin Wolf wrote:
>> If we managed to allocate the clusters, but then failed to write the
>> data, there's a good chance that we'll still be able to free the
>> clusters again in order to avoid cluster leaks (the refcounts are
>> cached, so even if we can't write them out right now, we may be able to
>> do so when the VM is resumed after a werror=stop/enospc pause).
>>
>> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
>> ---
>>   block/qcow2.h         |  1 +
>>   block/qcow2-cluster.c | 11 +++++++++++
>>   block/qcow2.c         |  2 ++
>>   3 files changed, 14 insertions(+)
> 
> Hmm, I wonder if this interacts poorly with my proposed test addition 
> for HUGE images, which is still pending review:
> https://lists.gnu.org/archive/html/qemu-devel/2018-06/msg05488.html
> https://lists.gnu.org/archive/html/qemu-devel/2018-04/msg04542.html
> 
> (time for me to go testing...)

Phew, my test didn't change (but I will go ahead and repost a v7 to fix 
the minor conflict in iotest numbering).

And that means I can also add for this series:

Tested-by: Eric Blake <eblake@redhat.com>

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