I'm trying to resize an ext4 filesystem on a Fedora 11 box. Using fsdisk and lvm, I was able to grow the partition and logical volume containing the filesystem. When I try to run resize2fs on the device containing the filesystem (/dev/sda2 in this case), I get: "Device or resource busy while trying to open /dev/sda2, Couldn't find valid filesystem superblock" I've tried this from a rescue disk that doesn't have the filesystem mounted, no joy. Maybe resize2fs doesn't know about ext4?