driver

SLASH kernel module

Testing

The test suite requires a physical V80 to be present and the module to be loaded into a running kernel.

Prerequisites

• A kernel built with CONFIG_GCOV_KERNEL=y (only needed for coverage runs).
• lcov and genhtml installed (only needed for coverage runs).
• The BDF identifier of the V80 card (e.g. 0000:03:00).
  • You may be able to retrieve the BDF identifier by running v80-smi list

Running the tests manually

Build the module and the test suite:

make          # builds slash.ko
make -C tests/ all

Load the module and rescan the PCI bus so the device nodes appear:

sudo insmod ./slash.ko
echo 1 | sudo tee /sys/bus/pci/rescan > /dev/null

Run the kselftest suite (must be run as root):

sudo make -C tests/ run

The suite produces TAP output. Each test fixture automatically tears down queue pairs on failure, so a failing test does not leave the device in a broken state.

Optional: override the DMA target address

The write_read_verify test defaults to DMA address 0x0. Set SLASH_TEST_DMA_ADDR to use a different address:

sudo SLASH_TEST_DMA_ADDR=0x100000000 make -C tests/ run

Running with code-coverage instrumentation

test_module.sh automates the full build → load → test → coverage cycle:

./test_module.sh <BBBB:DD:FF>

Replace <BBBB:DD:FF> with the BDF of the V80 (e.g. 0000:03:00).

The script:

1. Checks that the running kernel has CONFIG_GCOV_KERNEL=y.
2. Builds slash.ko with gcov instrumentation (make GCOV=1).
3. Builds the test suite.
4. Removes any currently-loaded slash module.
5. Resets the gcov counters.
6. Inserts the module and rescans the PCI bus.
7. Runs the full kselftest suite.
8. Removes the module.
9. Captures coverage with lcov and generates an HTML report in coverage/.

Open coverage/index.html in a browser to browse line-level coverage.