Greg Kroah-Hartman is a major Linux kernel developer.

As of April 2013[update], he is the Linux kernel maintainer for the -stable branch,[2] the staging subsystem,[2] USB,[2] driver core, debugfs, kref, kobject, and the sysfs kernel subsystems,[2] Userspace I/O (with Hans J. Koch),[2] and TTY layer.

He also contributes articles to LWN.net, the Linux news site.

Kroah-Hartman frequently helps in the documentation of the kernel and driver development through talks[7][8] and tutorials.

[9][10] In 2006, he released a CD image of material to introduce a programmer to working on Linux device driver development.