Thanks for your interest in contributing to rust-landlock!
The Landlock functionality exposed differs between kernel versions. In order to test all possible variations, the rust-landlock tests will run different subsets of tests based on the landlock support in the current kernel.
In order to fully test a change, it should be verified against a range of
kernel versions. This is done by the github actions CI, but is currently
challenging to do locally. For local development, running cargo test will
test against your currently running kernel version, which may result in some
tests being skipped.
The kernel to test against can be overridden using the LANDLOCK_CRATE_TEST_ABI
environmental variable. For more details see the comment in
compat.rs:current_kernel_abi().
For more information about Landlock ABIs see https://landlock.io/rust-landlock/landlock/enum.ABI.html