2.6 history, continued 2.6.8 (August 13, 2004) Mirror and snapshot support in device mapper Generic DMA improvements x86 NX support New symlink lookup mechanism SCSI operation permissions checking 2.6.9 (October 18, 2004) Block I/O barrier support Limited unprivileged memory locking Token-based thrashing control Kprobes USB "On The Go" support Out-of-line spinlocks A new I/O memory access mechanism (API change)