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charset="UTF-8" Content-Transfer-Encoding: quoted-printable User-Agent: Evolution 3.54.1 (3.54.1-1.fc41) Precedence: bulk X-Mailing-List: bpf@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 On Mon, 2024-12-16 at 18:39 +0100, Arthur Fabre wrote: [...] > It might not be possible to do them both entirely: clang also doesn't > know that bpf_tail_call() can return, so it assumes the callee() will > return a constant r0. It sometimes optimizes branches / loads out > because of this. Hm, haven't thought about this. You would need assembly to hide the r0 indeed.