Abstract

We describe the design and performance of code added to the Mach microkernel (Mach 4.0, version UK02p21) that permits one to build a Mach kernel that includes unmodified Linux device drivers. We have written emulation code to support all Linux 1.3.35 network and SCSI drivers for the ISA and PCI I/O buses. Emulation increases latency, but very little. The degree depends on both device and operation, and varies from 2 microseconds for receiving small (60 byte) network packets up to 197 microseconds for writing 16KB to an ISA SCSI device. 1 Introduction We describe the design and performance of code that permits one to build a Mach microkernel (Utah release 4.0, version UK02p21) that includes the completely unmodified source for device drivers that have been written for Linux (version 1.3.35). Our code, which consists of some changes and additions to Mach as well as run-time emulation of Linux calls, handles all of Linux's block drivers, network drivers, and SCSI host adapters for the IS...

Citations