The current kernel

2.6.11 (March 2, 2005)
Four-level page tables
InfiniBand support
Direct rendering rework
Reworked file readahead
ext3 in-inode extended attributes
Circular buffer pipe implementation
Latency reduction work
debugfs
Big kernel semaphore
ioctl() rework (API change)
Generic transport class (used by SCSI)

2.6.11.7 (April 7, 2005)
Various critical and security fixes