Comment by dralley
2 days ago
ABI is irrelevant. Only external APIs/ABIs are frozen, kernel-internal APIs have always been allowed to change from release to release. And Rust is only used for kernel-internal code like drivers. There's no stable driver API for linux.
External kernel APIs/ABIs are not frozen unless by external you only mean user space (eg externally loaded kernel modules try to keep up with dkms but source level changes require updates to the module source, often having to maintain multiple versions in one codebase with ifdef’s to select different kernel versions)
Userspace, yes.