From mboxrd@z Thu Jan  1 00:00:00 1970
From: peterz@infradead.org (Peter Zijlstra)
Date: Wed, 11 Nov 2015 20:23:52 +0100
Subject: [PATCH 2/2] arm64: bpf: add BPF XADD instruction
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Message-ID: <20151111192352.GT17308@twins.programming.kicks-ass.net>
To: linux-arm-kernel@lists.infradead.org
List-Id: linux-arm-kernel.lists.infradead.org

On Wed, Nov 11, 2015 at 07:50:15PM +0100, Daniel Borkmann wrote:
> Well, on that note, it's not like you just change the target to bpf in your
> Makefile and can compile (& load into the kernel) anything you want with it.
> You do have to write small, restricted programs from scratch for a specific
> use-case with the limited set of helper functions and intrinsics that are
> available from the kernel. So I don't think that "Programs that used to work
> will now no longer work." holds if you regard it as such.

So I don't get this argument. If everything is so targeted, then why are
the BPF instructions an ABI.

If OTOH you're expected to be able to transfer these small proglets,
then too I would expect to transfer the source of these proglets.

You cannot argue both ways.