CentOS - May 2013 - Failed to create /dev/loop0p* entries for partitions inside loopback devices

centos 6 failed to create entries under /dev for newly created loopback devices.
Any one know why? and how to fix/workaround it?

The steps to duplicate is pretty simple

dd if=/dev/zero of=/tmp/deleteme bs=1M count=100
losetup /dev/loop0 /tmp/deleteme
fdisk /dev/loop0?? ## created partitions 1, 2, etc.
fdisk -l /dev/loop0? ## confirmed that the partitions do exist
mkfs.ext3 /dev/loop0p1 ## failed here, the error prompt says that the
/dev/loop0p1 doesn't exist!
ls /dev/loop0p*? ## no entries

Please shed a light here, I'm running centos 6.4

Thanks.
Robert

On Fri, 24 May 2013, Gelen James wrote:
> centos 6 failed to create entries under /dev for newly created loopback
devices. Any one know why? and how to fix/workaround it?
>
> The steps to duplicate is pretty simple
>
> dd if=/dev/zero of=/tmp/deleteme bs=1M count=100
> losetup /dev/loop0 /tmp/deleteme
> fdisk /dev/loop0?? ## created partitions 1, 2, etc.
> fdisk -l /dev/loop0? ## confirmed that the partitions do exist
At this point, you need to run "kpartx -a /dev/loop0" (fdisk should 
have told you so).
> mkfs.ext3 /dev/loop0p1 ## failed here [...]
kpartx drops partitions into /dev/mapper, so the actual invocation 
would be

   mkfs.ext3 /dev/mapper/loop0p1

You can also use partprobe instead of kpartx, but I'm not as familiar 
with its operation.

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