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So unless our ARM users are substantially more exciting than the x86 crowd, it should all fall under the discussion from maintainer's summit: https://lwn.net/Articles/908464/ > My biggest concern is changing functionality of arbitrary functions by BPF. > I would much rather limit what functions BPF could change with some > annotation. > > int __bpf_modify foo() > { > ... > } > > > That way if somethings not working, you can see directly in the code that > the function could be modified by a BPF program, instead of getting some > random bug report because a function returned an unexpected result that the > code of that function could never produce. > The good news is that BPF generally confines the function replacement through struct ops interfaces. There are also explicit allow lists to limit functions where you can do return value overrides etc, so I think it's fair to say these concerns are already baked in. I'm sure they can be improved over the long term, but I don't think that's related to this set of functionality on ARM. -chris