[$] KRSI and proprietary BPF programs

The "kernel runtime security instrumentation" (or KRSI) patch set enablesthe attachment of BPF programs to every security hook in the kernel; LWN covered this work in December. That articlefocused on ABI issues, but it deferred another potential problem toour 2020 predictions: the possibility thatvendors could start shipping proprietary BPF programs for use withframeworks like KRSI. Other developers did pick up on the possibility that KRSI could be abused this way, though,leading to a discussion on whether KRSI should continue to allow the loading of BPF programs that do not carrya GPL-compatible license.