The limits of ABI stability in the kernel

At Chainguard, we want to re-use binary objects across Linux kernel builds of different major versions. For us this is useful for FIPS certification of individual kernel components while still allowing us to build new kernels and not pin the entire kernel forever. To achieve this, we performed a number of experiments with the kernel build system and spoke to other kernel developers about their efforts to achieve the same thing. I will discuss approaches to re-using binary objects, the limits of each, and how the linux kernel could have a stable(r) ABI.