May 12, 1992
	bart had a file system crash on a 4k block magnum file system.
	the first block was scrambled.
	the file system size was 0x7f000001
	there was a block in two files.
	one of those fileshad a block with address 0x7f000000.
	fixing the first block and fsize and clri'ing the files
	with bad blocks seemed to fix the problem

	it seemed to happen after a sync and then a reboot.