sd card reader on Thinkpad X61 tablet

need the following kernel modules before it’ll show up in fdisk -l:

sdhci_pci (depends on sdhci)
mmc_block (depends on mmc_core)

It is amusing to read the description of the mmc_block module though

This selects the disabler for the Ricoh MMC Controller. This proprietary controller is unnecessary because the SDHCI driver supports MMC cards on the SD controller, but if it is not disabled, it will steal the MMC cards away – rendering them useless. It is safe to select this driver even if you don’t have a Ricoh based card reader.