uclibc / # cat /usr/src/linux/.config | grep RAID
CONFIG_RAID_ATTRS=y
# CONFIG_BLK_DEV_3W_XXXX_RAID is not set
# CONFIG_SCSI_AACRAID is not set
# CONFIG_MEGARAID_NEWGEN is not set
# CONFIG_MEGARAID_LEGACY is not set
# CONFIG_MEGARAID_SAS is not set
# Multi-device support (RAID and LVM)
CONFIG_MD_RAID0=y
CONFIG_MD_RAID1=y
# CONFIG_MD_RAID10 is not set
# CONFIG_MD_RAID456 is not set
uclibc / # dmesg | grep RAID                     
md: Autodetecting RAID arrays.