There's a whole lot of device driver code out there that works so long as the device stays plugged in. But some devices, such as USB devices, can be removed while in use. This is a common cause of crashes on BSD systems. How can we make the operating system gracefully handle device removal?

This talk will discuss problems and race conditions we found in the NetBSD driver framework, how we've adapted the APIs to address them, and strategies for making device drivers robust to devices suddenly disappearing.