Writing Device Drivers

Hot Removal

The kernel checks the driver state, and if the driver instance is not open, the kernel can invoke the driver's detach(9E) entry point with the command DDI_DETACH. The driver instance checks its internal state and verifies whether it is safe to detach. If so, the driver frees resources, cancels timeouts, and returns success. At this point, the kernel can remove power from the slot and the hardware can be removed.