June 2, 2014
Few notes from release notes.
In Developer Preview 1 unsigned or improperly signed kexts will not be loaded. To use unsigned kexts during development, this strict check can be disabled by adding a “kext-dev-mode=1” boot arg.
Installing kernel extensions on systems running Developer Preview 1 may make your system un-bootable. To fix the issue, boot into the Recovery Partition and run the following:
kextcache -u /Volumes/