[dm-devel] kpartx fails 4k block partition

[Bryn M. Reeves]

On 03/12/2014 10:20 PM, Ross Anderson wrote:
> Under 0.50 multipath tools release, partitions are not being created for
> devices that are 4k Native.  This is under kernel 3.13.6, udev-208.
> 
> http://pastebin.com/Nnd4Ym4W

The devices below don't appear in your lsblk output so it's hard to say
whether the partitions kpartx prints for the devices are valid or not:

>     ##kpartx sfx4k
>     sfx4k1 : 0 2056 sfx4k 2048
>     sfx4k2 : 0 165068760 sfx4k 8192
>     ##kpartx samplelib
>     samplelib1 : 0 2056 samplelib 2048
>     samplelib2 : 0 1171863512 samplelib 8192

That said the tables above look perfectly plausible. It would help to
verify that if you could post the partition tables the devices contain
(preferably in sector units).

> kpartx -a 2 /dev/dm-2
> failed to stat() 2

What's that '2' doing there? The only thing kpartx expects following the
'-a' is the whole disk device:

    SYNOPSIS
       kpartx [-a | -d | -l] [-v] wholedisk

What happens when you run 'kpartx -a /dev/mapper/sfx4k? (or samplelib).

Regards,
Bryn.