This document provides instructions to create a Linux kernel binary. The kernel binary can be used during a gem5 Full System simulation. We assume the following initial directory structure before following the instructions in this README file:
Linux-kernel/ | |___ linux-configs # Folder with Linux kernel configuration files | |___ README.md # This README file
We have tested this resource compiling the following five LTS (long term support) releases of the Linux kernel:
In addition, we also have compiled and tested the following LTS releases for arm64 architecture only:
To compile the Linux binaries, follow these instructions (assuming that you are in src/Linux-kernel/ directory):
# will create a `linux` directory and download the initial kernel files into it. git clone https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git cd linux # replace version with any of the above listed version numbers git checkout v[version] # copy the appropriate Linux kernel configuration file from linux-configs/ cp ../linux-configs/config.[arch].[version] .config make -j`nproc`
After this process succeeds, the compiled Linux binary, named vmlinux, can be found in the src/Linux-kernel/linux. The final structure of the src/Linux-kernel/ directory will look as following:
Linux-kernel/ | |___ linux-configs # Folder with Linux kernel configuration files | |___ linux # Linux source | | | |___ vmlinux # The compiled Linux kernel binary | |___ README.md # This README file
Note on x86 Kernel Binaries: The above instructions for compiling x86 kernel binaries have been tested using the gcc 7.5.0 compile
The pre-build compiled x86 Linux binaries can be downloaded from the following links:
Note on ARM Kernel Binaries: A cross-compiler is needed to compile ARM kernel binaries on a x86 machine. We used gcc 10.3.0 (aarch64-linux-gnu-gcc-10)` to compile and test. In this resource, we are limited to arm64 architecture only.
The pre-build compiled ARM Linux binaries can be downloaded from the following links:
Alternatively to the vanilla kernel + linux-configs described above, it is also possible to compile a gem5 port of the Linux Kernel 4.14.0 for ARM. The repository can be cloned and built by following the following steps. It has a gem5 specific config file located in arch/arm64/configs/gem5\_defconfig under the linux directory.
git clone https://gem5.googlesource.com/arm/linux/ cd linux make ARCH=<arch> CROSS_COMPILE=<cross_compiler> gem5_defconfig make ARCH=<arch> CROSS_COMPILE=<cross_compiler> -j<num_cores>
Licensing: Linux is released under the GNU General Public License version 2 (GPLv2), but it also contains several files under other compatible licenses. For more information about Linux Kernel Copy Right please refer to here and here.