After install kernel 2.6.17 some /dev/md- appear

[Ambrogio]

Hi all,

After updating kernel with yum (now is 
2.6.17-1.2139_FC5 #1 SMP Fri Jun 23 12:40:11 EDT 2006 x86_64 x86_64
x86_64 GNU/Linux) I see some strange behaviours.

Some of them I solved, but I see this:

fdisk -l
Disk /dev/hda: 100.0 GB, 100030242816 bytes
255 heads, 63 sectors/track, 12161 cylinders
Units = cylinders of 16065 * 512 = 8225280 bytes

   Device Boot      Start         End      Blocks   Id  System
/dev/hda1               1         382     3068383+  12  Compaq diagnostics
/dev/hda2             383        1657    10241437+   7  HPFS/NTFS
/dev/hda3            2874       12161    74605860    5  Extended
/dev/hda4            1658        2873     9767520   83  Linux
/dev/hda5            2874        5364    20008926   83  Linux
/dev/hda6   *        5365        5402      305203+  83  Linux
/dev/hda7            5403        5663     2096451   82  Linux swap / Solaris
/dev/hda8            5664        5788     1004031    b  W95 FAT32
/dev/hda9            5789       12161    51191091   8e  Linux LVM

Partition table entries are not in disk order

Disk /dev/dm-0: 16.1 GB, 16106127360 bytes
255 heads, 63 sectors/track, 1958 cylinders
Units = cylinders of 16065 * 512 = 8225280 bytes

Disk /dev/dm-0 doesn't contain a valid partition table

Disk /dev/dm-1: 10.7 GB, 10737418240 bytes
255 heads, 63 sectors/track, 1305 cylinders
Units = cylinders of 16065 * 512 = 8225280 bytes

Disk /dev/dm-1 doesn't contain a valid partition table

Disk /dev/dm-2: 11.3 GB, 11366563840 bytes
255 heads, 63 sectors/track, 1381 cylinders
Units = cylinders of 16065 * 512 = 8225280 bytes

Disk /dev/dm-2 doesn't contain a valid partition table

What are this /dev/dm that I see?
I didn't have nothing configured like mirror software or raid.

Tnx
 Ambrogio