Re: [PATCH v2 01/18] migration: Fix file migration with fdset

[Fabiano Rosas <farosas@suse.de>]

Prasad Pandit <ppandit@redhat.com> writes:

> On Fri, 24 May 2024 at 00:38, Fabiano Rosas <farosas@suse.de> wrote:
>> This is further indicated by the presence of the 'offset'
>> argument, which indicates the start of the region where QEMU is
>> allowed to write.
>>
>> Fix the issue by replacing the O_TRUNC flag on open by an ftruncate
>> call, which will take the offset into consideration.
>>
>> +    if (ftruncate(fioc->fd, offset)) {
>> +        error_setg_errno(errp, errno,
>> +                         "failed to truncate migration file to offset %" PRIx64,
>> +                         offset);
>> +        object_unref(OBJECT(fioc));
>> +        return;
>> +    }
>> +
>
> * Should 'offset' be checked for > zero while ftruncating? Else it'll
> be same as O_TRUNC. Otherwise it looks fine.

That's the point. If offset==0 we truncate all the way, if not, we
truncate to the offset.

>
> Reviewed-by: Prasad Pandit <pjp@fedoraproject.org>

Thanks!