MkLinux on PA-RISC
Overview

MkLinux was a 1990s project led by Apple and Open Group Research Institute to port Linux hosted on top of a Mach microkernel (pmk1.1) for Apple PowerPC computers. It was used extensively in the 1990s on computers like PowerBooks. An Open Group research project ported MkLinux later to PA-RISC, supported by HP, first released in 1997.
MkLinux was the first free operating system that really worked on PA-RISC hardware, in contrast to the various Mach ports, which suffered from unfinished development and a lot of bugs on PA-RISC. MkLinux on PA-RISC built on the previous OSF/1 MK-PA, improved the underlying OSF PA-RISC/Mach kernel from MK-PA with Linux 2.0 kernel and included X11R6 patches, the GNU ELF compiler and debugger and complete /usr and /var directories.
MkLinux on PA-RISC system was rather slow, did not support shared libraries, software support was rather rudimentary and at the time of development PA-RISC workstations were not largely available to private end-users. However, MkLinux was the first real option for hobbyists with second-hand PA-RISC computers in the 1990s.
Together with Mach 4/Lites, MkLinux inspired the later, more modern PA-RISC open source ports of Linux and OpenBSD/hppa in the late 1990s, which still exist today.
Systems support
MkLinux supported PA-RISC 1.1 32-bit HP 9000 workstation computers:
- HP 9000 705, 710, 720, 730, 750 based on PA-7000 processors
- HP 9000 715, 725, 735, 755 based on PA-7100 processors
- 715/33 not supported
- HP 9000 712, 715, 725/100 based on PA-7100LC processors
- HP 9000 C100, C110 based on PA-7200 processors
Hardware support
MkLinux supported most on-board hardware but no expansion or third-party devices.
- SCSI internal single-ended, internal fast-wide-differential, GSC based fast-wide-differential, and EISA fast-differential drives and DAT tapes
- Builtin Ethernet
- GRX, CRX and Artist graphics
- HIL and PS/2
- Audio
- RS232 serial
- ASP and LASI chipsets
Releases
MkLinux was released in snapshot status with freely distributable source, binaries, and boot images.
It was available from the OSF Mall
but could be downloaded freely from FTP in 1997.
This was a more or less complete MkLinux distribution with pmk1.1 Mach kernel, MkLinux server, sources, root partition, /usr and /var content and X11R6.
The following releases
were available as source from the Open Group (OSF) and FTP servers.
- MkLinux for HP PA-RISC (first release): Support for few PA-RISC 1.1 workstations (1997)
The Open Group Research Institute (OSF RI) ended its involvement into MkLinux not later than 1998.
Documentation
Most sources and mirrors disappeared during the last years, as ownership of the website, resources and code transitioned a few times.
- MkLinux - Linux on the OSF Microkernel, The Open Group (1997, archived by CIRR 1999, current mirror MkLinux.org accessed 2022)
- MkLinux for HP PA-RISC, The Open Group (1997, archived by CIRR 1999, current mirror MkLinux.org accessed 2022)
- Release Notes for MkLinux on HP PA-RISC Descriptions on MkLinux and extensive installation instructions. The Open Group (1997, archived by CIRR 1999, current mirror MkLinux.org accessed 2022)
- ftp.mklinux.org/pub/hppa/, MkLinux sets at ftp.mklinux.org, The Open Group (1997, archived by CIRR 1999, current mirror SUNET.se accessed 2024)
- Software Mall - MkLinux Snapshot for HP PA-RISC, OSF (1998) archive.org
- A brief comparison of HP-UX and MkLinux on PA-RISC, Open Group (1997) archive.org
- Performance Improvements on the HP Precision Architecture, Open Group RI (1995?) archive.org