On Fri, 11 Jul 2003 11:00:41 BST, Joe Thornber said:

> If you want to use v4 you will have to update your tools
> (libdevmapper/lvm).  The latest tools at the time of writing are:
> 
> dmsetup + libdevmapper + replacement kernel patches for 2.4.20 & 2.4.21:
>   ftp://ftp.sistina.com/pub/LVM2/device-mapper/device-mapper-testing-new-vers
ion4-interface.tgz
> 
> Updated LVM2 tools to work with the above:
>   ftp://ftp.sistina.com/pub/LVM2/tools/LVM2.0-testing.tgz

The v4 interface does work with the 64-bit kdev_t patch in 2.5.75-mm1, fixing the
problems I noted the other day (I already had the updated libdevmapper and LVM2,
was missing the 2 patches for the v4 ioctl).