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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 5DB02C74A5B for ; Thu, 16 Mar 2023 22:35:56 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229879AbjCPWfz (ORCPT ); Thu, 16 Mar 2023 18:35:55 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:58914 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229608AbjCPWfy (ORCPT ); Thu, 16 Mar 2023 18:35:54 -0400 Received: from mail-ed1-x530.google.com (mail-ed1-x530.google.com [IPv6:2a00:1450:4864:20::530]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 63352C0819; Thu, 16 Mar 2023 15:35:53 -0700 (PDT) Received: by mail-ed1-x530.google.com with SMTP id cy23so13503141edb.12; Thu, 16 Mar 2023 15:35:53 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20210112; t=1679006152; h=content-transfer-encoding:cc:to:subject:message-id:date:from :in-reply-to:references:mime-version:from:to:cc:subject:date :message-id:reply-to; bh=3MeZF1Bnltb4cTSt6wYxqidPGeVX12qy/3riQTBs+FQ=; b=e7JBBD55E/sbAUTrjA4yCKyh/iwLIcYSJ7Dh7f+m8efvZ7fi0iAHU7FysC5bTxnp4C 5rOQnabWMZskVnGcZQYof7yQnfusUnSBM2oU2K5L8pTmeD71YHUFT5LdRcoCreODWRQ+ +WfXGmjaotOb4piSeovkFZyRDixX4jYuS+C0QsiDVP/B4qtClqVPy7O4m9rC2aH1w9pR qKX6HnsIuvvrx6OkKF8/4cjJKwKR8D9KmRyQt/Q5MT7gs12ZqvhMqdOmgQDfZGfQ9AOn w/Z+XG8NWLBBd+rxVgWHktK4OeGQj8+y/MxHcbvrE4FDZvnhpYFXwmKm9an1JdBJ6+nk tnjQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; t=1679006152; h=content-transfer-encoding:cc:to:subject:message-id:date:from :in-reply-to:references:mime-version:x-gm-message-state:from:to:cc :subject:date:message-id:reply-to; bh=3MeZF1Bnltb4cTSt6wYxqidPGeVX12qy/3riQTBs+FQ=; b=RYWhjrcqKhLGeeijOFvdMvZ1F9Qyp4aGBKOdkD60VD2e5VngCBx0LuTuxWjKqTzzNs eNuk65mGBE/olfm/VoVJGsS5LKisMvhom5WleMMmXG2BUpgOPFVlEoNNZrXwVsgzmoyU S+GEM9cJAIHnsBoTccuNiWt66ECmwNU8LDyjW8feYvQjyYVx/tA3JfPk8wxmpchBneff on7scrDFXMXNjVHR7l7odwXrHgyDiOuEDS8ucQRD242A9v7vqI9NzW8MXs9AUmhW9h9M 0K2iY8OsI0D9ozgQ719Y1K4c+i4SSvwlVrqv0iYl4fmOyOitRQRPcaSFyJgqb52AlKW0 IzGw== X-Gm-Message-State: AO0yUKUNrDakL0y2gE5I837czZK5Qr6JGMAn/aBmuWX3gv8jmg1jDz7e X9Y8BOCcbiGlMnPXsrdoh4PpYtz/KIauEc13dMw= X-Google-Smtp-Source: AK7set8Op/1RlWsPUJUsv5X6cNJgoSQ0K4GG8P8w/ls9UTWCcbGsRXbveRRq+GxzCwpzdJtn++ZTgXJBpAa01IuA7sE= X-Received: by 2002:a50:f602:0:b0:4fb:f19:881 with SMTP id c2-20020a50f602000000b004fb0f190881mr643969edn.3.1679006151854; Thu, 16 Mar 2023 15:35:51 -0700 (PDT) MIME-Version: 1.0 References: <20230315223607.50803-1-alexei.starovoitov@gmail.com> <20230315223607.50803-3-alexei.starovoitov@gmail.com> In-Reply-To: From: Alexei Starovoitov Date: Thu, 16 Mar 2023 15:35:40 -0700 Message-ID: Subject: Re: [PATCH bpf-next 2/2] selftests/bpf: Add test for bpf_kfunc_exists(). To: Andrii Nakryiko Cc: "David S. Miller" , Daniel Borkmann , Andrii Nakryiko , Martin KaFai Lau , David Vernet , Dave Marchevsky , Tejun Heo , Kumar Kartikeya Dwivedi , Network Development , bpf , Kernel Team Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable Precedence: bulk List-ID: X-Mailing-List: bpf@vger.kernel.org On Thu, Mar 16, 2023 at 1:34=E2=80=AFPM Andrii Nakryiko wrote: > > On Wed, Mar 15, 2023 at 3:36=E2=80=AFPM Alexei Starovoitov > wrote: > > > > From: Alexei Starovoitov > > > > Add load and run time test for bpf_kfunc_exists() and check that the ve= rifier > > performs dead code elimination for non-existing kfunc. > > > > Signed-off-by: Alexei Starovoitov > > --- > > we have prog_tests/ksyms_btf.c and progs/test_ksyms_weak.c which do > these kind of tests for variable ksyms, let's just add kfunc ksyms > there (user-space part has also checking that captured pointer value > is correct and stuff like that, we probably want that for kfuncs as > well) That's where initially I tried to place the test, but test_ksyms_weak.c is used in light skeleton as well which is pickier about resolving ksyms. libbpf was lucky in that sense. It does: if (btf_is_var(t)) err =3D bpf_object__resolve_ksym_var_btf_id(obj, ext); else err =3D bpf_object__resolve_ksym_func_btf_id(obj, ext); while gen_loader for lksel assumes bpf_call insn as the only option for kfu= nc. I figured I'll add basic support for kfunc detection first and address lksel later when I have more time. Hence the reason to pick: .../selftests/bpf/progs/task_kfunc_success.c | 14 +++++++++++++- as a location for the test.