Fall 2011
xv6
Creative Commons License

Tools Used in 6.828

If you use the MIT Athena machines that run Linux, then all the software tools you will need for this course are located in the 6.828 locker: just type 'add -f 6.828' to get access to them. If you would like to compile and run the tools on your own machine, however, here is the information you need. We cannot guarantee that these tools will run on your computer, but they should run on recent versions of Linux.

It should be possible to get this development environment running under windows with the help of Cygwin. Install cygwin, and be sure to install the flex and bison packages (they are under the development header).

For an overview of useful commands in the tools used in 6.828, see the lab tools guide.

Compiler Toolchain

Most modern Linuxes and BSDs have an ELF toolchain compatible with the 6.828 labs. That is, the system-standard gcc, as, ld and objdump should just work. The 6.828 lab makefile should automatically detect this. However, if your machine is in this camp and the makefile fails to detect this, you can override it by adding the following line to conf/env.mk:

GCCPREFIX=

If you are using something other than standard x86 Linux or BSD, you will need the GNU C compiler toolchain, configured and built as a cross-compiler for the target 'i386-jos-elf', as well as the GNU debugger, configured for the i386-jos-elf toolchain. You can download the specific versions we used via these links, although any recent versions of gcc, binutils, and GDB should work:

Once you've unpacked these archives, run the following commands as root:

# cd binutils-2.21.1
# ./configure --target=i386-jos-elf --disable-nls
# make
# make install
# cd ../gcc-4.5.1
# ./configure --target=i386-jos-elf --disable-nls --without-headers \
              --with-newlib --disable-threads --disable-shared \
              --disable-libmudflap --disable-libssp
# make
# make install
# cd ../gdb-6.8
# ./configure --target=i386-jos-elf --program-prefix=i386-jos-elf- \
              --disable-werror
# make
# make install

Then you'll have in /usr/local/bin a bunch of binaries with names like i386-jos-elf-gcc. The lab makefile should detect this toolchain and use it in preference to your machine's default toolchain. If this doesn't work, there are instructions on how to override the toolchain inside the GNUmakefile in the labs.

QEMU Emulator

QEMU is a modern and fast PC emulator. QEMU version 0.15 is set up on Athena for x86 machines in the 6.828 locker.

Unfortunately, QEMU's debugging facilities, while powerful, are somewhat immature, so we highly recommend you use our patched version of QEMU instead of the stock version that may come with your distribution. The version installed on Athena is already patched. To build your own patched version of QEMU:

  1. Clone the 6.828 QEMU git repository
    git clone http://pdos.csail.mit.edu/6.828/qemu.git -b 6.828-0.15
  2. On Linux, you may need to install the SDL development libraries to get a graphical VGA window. On Debian/Ubuntu, this is the libsdl1.2-dev package.
  3. Configure the source code
    Linux: ./configure --disable-kvm [--prefix=PFX] [--target-list="i386-softmmu x86_64-softmmu"]
    OS X: ./configure --disable-kvm --disable-sdl [--prefix=PFX] [--target-list="i386-softmmu x86_64-softmmu"]
    The prefix argument specifies where to install QEMU; without it QEMU will install to /usr/local by default. The target-list argument simply slims down the architectures QEMU will build support for.
  4. Run make && make install

Questions or comments regarding 6.828? Send e-mail to the TAs at 6.828-staff@pdos.csail.mit.edu.

Top // 6.828 home // Last updated Wednesday, 14-Sep-2011 13:26:47 EDT