From: Daniel Borkmann <dan...@iogearbox.net> Date: Wed, 09 Aug 2017 19:00:58 +0200
> On 08/09/2017 06:55 PM, David Miller wrote: >> From: Daniel Borkmann <dan...@iogearbox.net> >> Date: Wed, 9 Aug 2017 12:23:53 +0200 >> >>> [1] https://github.com/borkmann/llvm/tree/bpf-insns >> >> How is this "backwards compatible"? >> >> If someone takes a new LLVM and tries to load those programs >> into an older kernel they will be rejected. >> >> There appears to be no effort to make things work cleanly in >> that situation at all. > > No, that was just the patch I used for LLVM to enable the > insns, so not the final one that will be submitted there > officially where we have a switch to enable/disable this > functionality. So how does this switch work and how are people expected to use this switch? What is the default value and is it ever expected to change in the future? Yeah this seems hella awesome to get cilium programs smaller and faster in a restricted environment where you control the running kernel and everything. But from a review perspective one should be completely uninterested in that. So, generally speaking how does this all pan out? I seriously doubt the wisdom of this. You'll have to convince me of the long term viability and whether we ever get to the point where everyone can benefit from this. :)