Hi Laurent,

Laurent Riffard wrote:
>>>>>>  device-mapper: reload ioctl failed: Invalid argument
...
>> works for me with 2.6.17-4mdv kernel
>> maybe something related to your kernel version?
> 
> Yes, you seem to be right: it does work with 2.6.17-2mdv or 2.6.17-4mdv, 
> but it fails with 2.6.18-rc6-mm1.

I reproduced the problem on my host, too.
I found a change in -mm which would cause this problem
and attached patch fixed it.

I'll post it to linux-kernel as well.

Thanks,
-- 
Jun'ichi Nomura, NEC Corporation of America