I'm using your udm1 patch set to linux 2.6.6-rc2. The man page for lvcreate says the chunksize parameter for a snapshot can be a power of two value between 4k and 1024k. When I try --chunksize 1024, I hit a BUG() in the bvec_index() function. Putting some checking code into snapshot_ctr(), I observe that when the lvcreate --chunksize 1024 parameter is used, snapshot_ctr() reports a chunksize of 2048. This is the value just after the simple_strtoul() call. So, why is the value being doubled (by the lvcreate command?). Also, why is there no range check on the value in snapshot_ctr(), with a error code failure, rather than a BUG() call in bvec_index? Thanks! Dave Olien