From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-12.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id EA25AC433ED for ; Tue, 11 May 2021 22:47:59 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id AD5806192B for ; Tue, 11 May 2021 22:47:59 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229714AbhEKWtF (ORCPT ); Tue, 11 May 2021 18:49:05 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:49066 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229637AbhEKWtF (ORCPT ); Tue, 11 May 2021 18:49:05 -0400 Received: from mail-yb1-xb33.google.com (mail-yb1-xb33.google.com [IPv6:2607:f8b0:4864:20::b33]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 5848DC061574 for ; Tue, 11 May 2021 15:47:58 -0700 (PDT) Received: by mail-yb1-xb33.google.com with SMTP id e190so28389571ybb.10 for ; Tue, 11 May 2021 15:47:58 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc; bh=WbamoN6Sj/reLeeB02eyzNwzl2x3pUKQzro1Y46eDTg=; b=Ynr+GxVsh5SHb0HwnZP9pr1Y5PSEt1/Vcoo+iihyqlmSIhBtihtxGuJ7wymf9W/C9x KN6fhFqsugJSPr9UDne4W+xtC4LwbFnPiBbhNGM89OfA6xX8boB5hGaYsfvRlsl8gxtg vlMGkp8bUVloOWn738DtF7MvIMyYwbDd6Aw8DptFPrWBt63W6qZOIXFqShBHmhRrsoRH /xdyFcDTvdmxqAvwcu5uhAkyAGS0g+j/zTr2oBiJZBwiwg+b/+SAP7Kjw6/l5XCU5wRf C2Rx7DdL54K3Oy6TQltmV2YDuM5DZ0ANPwvVd++tyM2qN5v7AO3LNDAwn5NIgMrUfZDp c9+A== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc; bh=WbamoN6Sj/reLeeB02eyzNwzl2x3pUKQzro1Y46eDTg=; b=h/mTmOLbLNmUoUIUZe5oiazoshMUc022Ta2pEp0JeBoT15lJIujwd9JCRhrOkVJaQL KF5FY1wY0iZFgSHkAv3990R7wVwgfovGLGSKoEDTkXxWVS+jMV17oswhiVraE1TOKLmA KkK1oSA7y0LPrMA0RAPKDj8h6etQ7pnZT7Ngkt2hAPSbsa94/FdYKIje+N3XiXvKDnG8 FrzEQk/4yOMZPiB+FFk/kX0rTVDDToNzdbRHY0pz0rTPbO5b2jUVYcUojSlE/Psf8RQW smX5D1yQoQ7xvfHmxNqsHoXwuWmRQ+b73ZOXjQphvBVgM9mc4dGdh8VyAO+e9kAi+EHR oJ6w== X-Gm-Message-State: AOAM530pUGaNbTv4dKr2ZRJwq6nAhzVvKSrL9H5xqvUezV6Nx5afD4Ms q4FVnOFzOyp5BadA2t3nFNfw+9wN7WgY6aGAPjk= X-Google-Smtp-Source: ABdhPJx3zxD29M44qaWbo4oyHxvSjcRnsp+SpE0u2dGbKFBLiZ4kJAia3GIS1V1Kq5Go8RpM5o1tojcI5Bep2OKY8BQ= X-Received: by 2002:a25:9942:: with SMTP id n2mr45817581ybo.230.1620773277644; Tue, 11 May 2021 15:47:57 -0700 (PDT) MIME-Version: 1.0 References: <20210508034837.64585-1-alexei.starovoitov@gmail.com> <20210508034837.64585-9-alexei.starovoitov@gmail.com> In-Reply-To: <20210508034837.64585-9-alexei.starovoitov@gmail.com> From: Andrii Nakryiko Date: Tue, 11 May 2021 15:47:46 -0700 Message-ID: Subject: Re: [PATCH v4 bpf-next 08/22] bpf: Introduce fd_idx To: Alexei Starovoitov Cc: "David S. Miller" , Daniel Borkmann , Andrii Nakryiko , john fastabend , bpf , Kernel Team Content-Type: text/plain; charset="UTF-8" Precedence: bulk List-ID: X-Mailing-List: bpf@vger.kernel.org On Fri, May 7, 2021 at 8:48 PM Alexei Starovoitov wrote: > > From: Alexei Starovoitov > > Typical program loading sequence involves creating bpf maps and applying > map FDs into bpf instructions in various places in the bpf program. > This job is done by libbpf that is using compiler generated ELF relocations > to patch certain instruction after maps are created and BTFs are loaded. > The goal of fd_idx is to allow bpf instructions to stay immutable > after compilation. At load time the libbpf would still create maps as usual, > but it wouldn't need to patch instructions. It would store map_fds into > __u32 fd_array[] and would pass that pointer to sys_bpf(BPF_PROG_LOAD). > > Signed-off-by: Alexei Starovoitov > --- Acked-by: Andrii Nakryiko > include/linux/bpf_verifier.h | 1 + > include/uapi/linux/bpf.h | 16 ++++++++---- > kernel/bpf/syscall.c | 2 +- > kernel/bpf/verifier.c | 47 ++++++++++++++++++++++++++-------- > tools/include/uapi/linux/bpf.h | 16 ++++++++---- > 5 files changed, 61 insertions(+), 21 deletions(-) > [...]