On Wed, Feb 27, 2013 at 11:04:46AM -0500, Dave Jones wrote:

 > > EXT4-fs error (device sdb1): htree_dirblock_to_tree:919: inode #172235804: block 152052301: comm ls: bad entry in directory: rec_len is smaller than minimal - offset=0(0), inode=0, rec_len=0, name_len=0

Yeah, looks similar.  The missing files/dirs reappeared when I
booted an older kernel, so it looks like the corruption doesn't
hit the disk.  Fsck (1.42.5) didn't find anything either.

I suspect I see the problem...   can you send me the results of 

  debugfs -R "stat <172235804>" /dev/sdb1

to confirm?

Thanks,

						- Ted