Covcc

Generate linux kernel module coverage reports without recompiling the kernel.

Usage

Compile and install

# compile
cd src && make

# install
make install

# or install to other path
make PREFIX=/path/to/your/bin install

This project contain 2 commands:

• covcc: inject counter and code into the module code and stat the coverage.
• cov_reader: read the counter and generate report, etc.

Usage of covcc

Do not need to recompile the kernel or change any kernel config

Do not need to change the module code or makefile

Just use make CC=covcc to recompile the module, and everything is ready.

covcc use gcc as default compiler, export ORIG_CC=your_cc before make to overide it. you can also export COVDEBUG=1 to show more messages.

Usage of cov_reader

cov_reader is used to obtain coverage date from the kernel. !!! cov_reader must have /proc/kcore and /proc/kallsyms available !!!

some example:

# read coverage of mymodule and generate report for mymodule.c
cov_reader -m mymodule mymodule.c

# read coverage from kernel space and save to file
cov_reader -o mymodule_from_1.data

# collect coverage from another machine
cov_reader -o mymodule_from_2.data

# merge coverage data and generate reports for c sources, output summary.
cov_reader -a -i mymodule_from_1.data -i mymodule_from_2.data /path/to/mysrc/*.c

use --xml to generate cobertuna reports

have fun.