program vol_id reads sectors at end of media
 

When I insert an SD(HC) card into the SD reader slot of my ASUS EEE PC900, there is a program named vol_id, which appears to be part of udev, that tries to read some of the LAST sectors of the media device. Anyone know what this program is trying to accomplish with that? Is there where it is expecting some volume ID information to be stored? Should partitions avoid that location?

The reason I ask is there seems to be some problem with accessing the last few sectors of SD(HC) cards on this computer. Under Slackware I don't run udev at all and I have no problem with the SD(HC) card reader. But under Ubuntu, it fails because the vol_id program is doing I/O requests that are triggering the problem (requests in the last 8 sectors are causing it to hang ... I don't know yet if it is a driver problem or a hardware problem).