KernelModule

Kernel Version: 6.1.115-126.197
Architecture: x86_64
Linux version: Amazon Linux 2023.6.20241111
cwd: /home/ec2-user/Grant/KernelModule

Step 0: Set up

sudo yum groupinstall "Development Tools" -y
sudo yum install cmake -y
mkdir just_wasm
mkdir just_kernel
mkdir combined_wasm_kernel

In just_wasm create main.c and hello_wasm.c In just_kernel create hello_module.c and Makefile

Step 1: Loading the kernle in module (not wasm3)

make

make -C just_kernel

To load the kerel module into the kernel

sudo insmod just_kernel/hello_module.ko

Check kernel logs to see printk message was logges

sudo dmesg | tail

Remove module v

sudo rmmod hello_module
sudo dmesg | tail

Step 2: Run wasm3 code in wasm3 runtime (no kernel involved)

git clone https://github.com/wasm3/wasm3.git

To compile C code into WebAssembly. Install Emscripten Emscripten's official installation guide:

git clone https://github.com/emscripten-core/emsdk.git
cd emsdk
./emsdk install latest
./emsdk activate latest
source ./emsdk_env.sh

export paths to ~/.bashrc :
export PATH=$PATH:$HOME/Grant/KernelModule/wabt/build
source /home/ec2-user/Grant/KernelModule/emsdk/emsdk_env.sh

Compile hello_wasm.c

emcc just_wasm/hello_wasm.c \
    -s STANDALONE_WASM=1 \
    -s ERROR_ON_UNDEFINED_SYMBOLS=0 \
    --no-entry \
    -o just_wasm/hello_wasm.wasm

Build wasm executable If you haven't already cloned wasm3, do it first

cd wasm3
mkdir build
cd build
cmake ..
make
cd ../..

Compile main.c

gcc just_wasm/main.c -I./wasm3/source ./wasm3/build/source/libm3.a -lm -o just_wasm/wasm3_runner

run wasm3

./just_wasm/wasm3_runner

Step 3: Run Wasm3 inside the kernel

Convert WASM binary to C header file add definitions ...

xxd -i just_wasm/hello_wasm.wasm > combined_wasm_kernel/include/wasm_binary.h

Create kernel_wasm3.c and Makefile see directory combined_wasm_kernel