CS 395T: Tools

All of the tools that you need to execute and complete the labs are on the Linux CS department machines.

If you wish to compile and run the tools on your own machine, the information that you need is as follows. Note that we cannot guarantee that these tools will run on your computer, and we cannot support these tools on your own computer. However, the tools should run on recent versions of Linux. The tools should also run 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).

Compiler Toolchain

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


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 versions that are known to work with JOS via the following links, although more recent versions of gcc and binutils, and GDB should work too:

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

# cd binutils-2.19
# ./configure --target=i386-jos-elf --disable-nls
# make
# make install
# cd ../gcc-4.1.2
# ./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- \
# 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 0.10.6 is set up on the UTCS Linux machines.

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 the UTCS machines is already patched. To build your own patched version of QEMU:

  1. Download and unpack the pre-patched 0.10.6 source tarball.
  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 [--prefix=PFX] [--target-list="i386-softmmu x86_64-softmmu"]
    OS X: ./configure --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

Alternatively, you can download the official 0.10.6 source tarball from the QEMU homepage and apply the following patches:

i386-debug Use DS-relative virtual addresses instead of linear addresses in the GDB stub.
info-mem Fix "info mem" in the QEMU monitor to not skip the last mapped memory range.
info-pg Add "info pg" to the QEMU monitor that prints the page table.
e100 Fixes bugs in QEMU's simulated E100 and adds E100 debugging.
pcap Adds packet capture support.
option Adds the -pcap and -debug-e100 command line options used by e100 and pcap.

Last updated: Fri Aug 27 19:07:52 -0500 2010 [validate xhtml]