Linux emulationD1335047570Asl#Linuxemu is a program that can execute Linux/i386 ELF binaries on#Plan9. It was started by Russ Cox and development was continued by#cinap_lenrek. Please contact cinap_lenrek AT gmx DOT de with bug#reports or improvements.##SOURCE##[/n/sources/contrib/cinap_lenrek/linuxemu3.tgz |#http://plan9.bell-labs.com/sources/contrib/cinap_lenrek/linuxemu3.tgz]##[http://9hal.ath.cx/usr/cinap_lenrek/linuxemu3.tgz |#http://9hal.ath.cx/usr/cinap_lenrek/linuxemu3.tgz]##DOCUMENTATION##Documentation is provided in the doc directory:##! doc/linuxemu.txt#! doc/todo.txt##INSTALLATION##! tar xzf linuxemu3.tgz#! cd linuxemu3#! mk#! mk install##BOOTSTRAP##You need a Linux rootfilesystem packed in a tarball. Go! Get some#Linux rootfs:##[http://9hal.ath.cx/usr/cinap_lenrek/mroot-linuxemu.tbz |#http://9hal.ath.cx/usr/cinap_lenrek/mroot-linuxemu.tbz]##[http://plan9.stanleylieber.com/linuxemu/mroot.tgz |#http://plan9.stanleylieber.com/linuxemu/mroot.tgz]##The -linuxemu version contains no symlinks and can be extracted with#plain plan9 tools bunzip/tar.##The mroot.tgz version contains the same Debian Sarge base as#-linuxemu, but with several additional packages pre-installed:##! 9base#! dmenu-4.1.1#! dwm-5.8.2#! gcc 3.3.5#! linux-kernel-headers#! mercurial 0.9.4#! opera 10.11#! python 2.3.5#! xlib-dev##and more. View its [setup |#http://plan9.stanleylieber.com/linuxemu/setup] file for more details.##You can create your own with debootstrap on Debian Linux, or help#write an installer that unpacks and installs Slackware on Plan 9...#In any case, linuxemu is not hardwired to any Linux distribution!##RUNNING##Use the provided "linux" script to chroot into your Linux rootfs.#The "linux" script is neccesary because for Linux programs to run,#shared libraries from your rootfs have to appear at /lib and#/usr/lib, while configuration files are expected to be in /etc. The#script will build a private namespace and bind the Linux rootfs over#the Plan 9 root. the original Plan 9 namespace is mounted at /9.##! linux -r ./mroot /bin/bash -i##If the -r option is omitted, the Linux rootfs defaults to#/sys/lib/linux. you may put your Linux rootfs there or add a bind to#your $home/lib/profile.##In the Linux rootfs, /etc/resolv.conf should be changed to match#your network nameserver. In addition, /etc/apt/sources.list should#be updated to a working Debian mirror. (Sarge packages can still be#accessed at deb http://archive.debian.org/debian-archive/debian#sarge main)##EXAMPLES##Linux X11 programs may be used in conjunction with the Plan 9 [equis#| http://www.plan9.bell-labs.com/wiki/plan9/X11_installation] X11#contrib package. For example, to run the Opera web browser under#your Linux rootfs, start equis in a rio window, chroot into your#LInux rootfs and:##! dwm &#! opera &##Opera should (eventually) appear in the equis window. A window#manager (this example uses dwm) is recommended so that X11 programs#work properly.##DEBUGGING##If linuxemu crashes, use acid to figure out whats going on:##! mk acid#! acid -l linuxemu.acid <pid>##Then you can issue the following commands:##! ustk() dump a (userspace) stacktrace for the current thread#! umem(Current()) dump the memory mappings#! ufds(Current()) dump the filedescriptor table#! utrace(Current()) dump the internal tracebuffer (enabled by -d option)##Use xasm()/xcasm() for disassembly for Linux code.##You can also enable full trace logging:##! linux -r ./mroot -dd /bin/bash -i >[2]/tmp/linuxemu.log##This slows linuxemu down. In case of race conditions, it often#happens that the bug disapears when doing full trace logging!##NPTL##If you get one of these errors:##! cannot set up thread-local storage: cannot set up LDT for thread-local storage##This is glibc/libpthread complaining! The problem is the following:#glibc on i386 decided at some point to use the extra segment#registers GS and FS as an indirection pointer for thread local#storage. The operating system kernel therfore must have a mechanism#to let userspace change descriptor table entries and swap them#in/out on context switch.##To make it work here are several options:##1) Recompile and link the program with a pre NPTL version of glibc.##2) On some distributions, a non-tls version of libc/libpthread is#available. in the -linuxemu fsroot, the NPTL version is in /lib/tls,#the older version is in /lib. By renaming /lib/tls to#/lib/_tls_disabled_ the loader will use the non-tls version.##3) Cinap made a kernel patch that adds support for per process#descriptors to Plan 9:##[http://plan9.bell-labs.com/sources/contrib/cinap_lenrek/segdescpatch | /n/sources/contrib/cinap_lenrek/segdescpatch]##[http://9hal.ath.cx/usr/cinap_lenrek/segdescpatch.tgz |#http://9hal.ath.cx/usr/cinap_lenrek/segdescpatch.tgz]##The above patch adds the files gdt and ldt to devarch (#P).#
Linux emulation
D1335047570
Asl
#Linuxemu is a program that can execute Linux/i386 ELF binaries on
#Plan9. It was started by Russ Cox and development was continued by
#cinap_lenrek. Please contact cinap_lenrek AT gmx DOT de with bug
#reports or improvements.
#
#SOURCE
#
#[/n/sources/contrib/cinap_lenrek/linuxemu3.tgz |
#http://plan9.bell-labs.com/sources/contrib/cinap_lenrek/linuxemu3.tgz]
#
#[http://9hal.ath.cx/usr/cinap_lenrek/linuxemu3.tgz |
#http://9hal.ath.cx/usr/cinap_lenrek/linuxemu3.tgz]
#
#DOCUMENTATION
#
#Documentation is provided in the doc directory:
#
#! doc/linuxemu.txt
#! doc/todo.txt
#
#INSTALLATION
#
#! tar xzf linuxemu3.tgz
#! cd linuxemu3
#! mk
#! mk install
#
#BOOTSTRAP
#
#You need a Linux rootfilesystem packed in a tarball. Go! Get some
#Linux rootfs:
#
#[http://9hal.ath.cx/usr/cinap_lenrek/mroot-linuxemu.tbz |
#http://9hal.ath.cx/usr/cinap_lenrek/mroot-linuxemu.tbz]
#
#[http://plan9.stanleylieber.com/linuxemu/mroot.tgz |
#http://plan9.stanleylieber.com/linuxemu/mroot.tgz]
#
#The -linuxemu version contains no symlinks and can be extracted with
#plain plan9 tools bunzip/tar.
#
#The mroot.tgz version contains the same Debian Sarge base as
#-linuxemu, but with several additional packages pre-installed:
#
#! 9base
#! dmenu-4.1.1
#! dwm-5.8.2
#! gcc 3.3.5
#! linux-kernel-headers
#! mercurial 0.9.4
#! opera 10.11
#! python 2.3.5
#! xlib-dev
#
#and more. View its [setup |
#http://plan9.stanleylieber.com/linuxemu/setup] file for more details.
#
#You can create your own with debootstrap on Debian Linux, or help
#write an installer that unpacks and installs Slackware on Plan 9...
#In any case, linuxemu is not hardwired to any Linux distribution!
#
#RUNNING
#
#Use the provided "linux" script to chroot into your Linux rootfs.
#The "linux" script is neccesary because for Linux programs to run,
#shared libraries from your rootfs have to appear at /lib and
#/usr/lib, while configuration files are expected to be in /etc. The
#script will build a private namespace and bind the Linux rootfs over
#the Plan 9 root. the original Plan 9 namespace is mounted at /9.
#
#! linux -r ./mroot /bin/bash -i
#
#If the -r option is omitted, the Linux rootfs defaults to
#/sys/lib/linux. you may put your Linux rootfs there or add a bind to
#your $home/lib/profile.
#
#In the Linux rootfs, /etc/resolv.conf should be changed to match
#your network nameserver. In addition, /etc/apt/sources.list should
#be updated to a working Debian mirror. (Sarge packages can still be
#accessed at deb http://archive.debian.org/debian-archive/debian
#sarge main)
#
#EXAMPLES
#
#Linux X11 programs may be used in conjunction with the Plan 9 [equis
#| http://www.plan9.bell-labs.com/wiki/plan9/X11_installation] X11
#contrib package. For example, to run the Opera web browser under
#your Linux rootfs, start equis in a rio window, chroot into your
#LInux rootfs and:
#
#! dwm &
#! opera &
#
#Opera should (eventually) appear in the equis window. A window
#manager (this example uses dwm) is recommended so that X11 programs
#work properly.
#
#DEBUGGING
#
#If linuxemu crashes, use acid to figure out whats going on:
#
#! mk acid
#! acid -l linuxemu.acid <pid>
#
#Then you can issue the following commands:
#
#! ustk() dump a (userspace) stacktrace for the current thread
#! umem(Current()) dump the memory mappings
#! ufds(Current()) dump the filedescriptor table
#! utrace(Current()) dump the internal tracebuffer (enabled by -d option)
#
#Use xasm()/xcasm() for disassembly for Linux code.
#
#You can also enable full trace logging:
#
#! linux -r ./mroot -dd /bin/bash -i >[2]/tmp/linuxemu.log
#
#This slows linuxemu down. In case of race conditions, it often
#happens that the bug disapears when doing full trace logging!
#
#NPTL
#
#If you get one of these errors:
#
#! cannot set up thread-local storage: cannot set up LDT for thread-local storage
#
#This is glibc/libpthread complaining! The problem is the following:
#glibc on i386 decided at some point to use the extra segment
#registers GS and FS as an indirection pointer for thread local
#storage. The operating system kernel therfore must have a mechanism
#to let userspace change descriptor table entries and swap them
#in/out on context switch.
#
#To make it work here are several options:
#
#1) Recompile and link the program with a pre NPTL version of glibc.
#
#2) On some distributions, a non-tls version of libc/libpthread is
#available. in the -linuxemu fsroot, the NPTL version is in /lib/tls,
#the older version is in /lib. By renaming /lib/tls to
#/lib/_tls_disabled_ the loader will use the non-tls version.
#
#3) Cinap made a kernel patch that adds support for per process
#descriptors to Plan 9:
#
#[http://plan9.bell-labs.com/sources/contrib/cinap_lenrek/segdescpatch | /n/sources/contrib/cinap_lenrek/segdescpatch]
#
#[http://9hal.ath.cx/usr/cinap_lenrek/segdescpatch.tgz |
#http://9hal.ath.cx/usr/cinap_lenrek/segdescpatch.tgz]
#
#The above patch adds the files gdt and ldt to devarch (#P).
#