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=-6.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE, SPF_PASS autolearn=no 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 5FF10C4741F for ; Fri, 25 Sep 2020 17:36:58 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id ED634235F9 for ; Fri, 25 Sep 2020 17:36:57 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="cujWZWU8" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729653AbgIYRg4 (ORCPT ); Fri, 25 Sep 2020 13:36:56 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:54812 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727812AbgIYRgz (ORCPT ); Fri, 25 Sep 2020 13:36:55 -0400 Received: from mail-yb1-xb41.google.com (mail-yb1-xb41.google.com [IPv6:2607:f8b0:4864:20::b41]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id AE199C0613CE; Fri, 25 Sep 2020 10:36:55 -0700 (PDT) Received: by mail-yb1-xb41.google.com with SMTP id v60so2530884ybi.10; Fri, 25 Sep 2020 10:36:55 -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=zZpRGIpf6h/aLDjQFUhOtDraQ6nKlUQ/ODEe9CGcDmc=; b=cujWZWU8IghE94FXDBFzzIKGrFjKmylSufF0j/hVSTuXBKM86g01jOvAobW92zW7cM +zsy0hqbeAeRHpAjnBmIv8s6U3mrgj261Nxw4R7o51yhomJUvu+3stONpXN0Ptkf6R5P ezagbL39cN6s6hEb/7m2ooP5E4F84YwQDn8fEjuKJ6JE6lhj/aNVXfRStdQB40Woo4e9 AaP8lxoCuqP+RK2JboOcWyHdTRe8a/cxAXTClTu8K6yH9TuJjeUfieBYG0CzCnEaYHXs iism18H0r9+sKkywsK3ach/nD4Rb8oLivU+lNN6Znuau3BTOfNoGDseRsdueozz4SxSo t8cA== 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=zZpRGIpf6h/aLDjQFUhOtDraQ6nKlUQ/ODEe9CGcDmc=; b=W2td9uoBKUAmSGayzPij5VM2L0zYtGcdwsptwN3EJ1POy9t6Jh5yHNxPrJbUOmw/rG DrcJWB8RZ9Rv1KeORsuUHV3wGCZKm3XzE1IXuNz+RQqboNPud1bKrAgDxHsQ8SVW+FCK DAH+QKJ9aJn73/nWMXlGpFd1ZXS+fFdgARMb2E4AO69iOqTZ2qaPzoR7gGiEsKt9zs9g BxfWRVSYReHTdazFqN39c0Eg2FGgD5pv1WtxAKBdtjGln+LjiJFHdzvExKxkFnKjOzVS i/vEYKZ3vuZnJ+890xB7kOcyWgKMyBdmXuYUtJQa+BBQcn1pzqwdb1R4MlGxOG/1RT9/ RiLg== X-Gm-Message-State: AOAM533lKAsHoUVIMi2Nt/2NzwNptH+eUU7TfLEy21ezraUQ0FGbJtxI DcAlbuOz8yxcGly1Rx9UW1uQUQ2E+R0nUbPG4msc7Tws39cB1DAP X-Google-Smtp-Source: ABdhPJxcScgubceKQGCd2YGjstpAhFXV+DIbP3KAs6SqVOIEK/EzRliRGa84SmGu6OoNz8sDo/BnrefAqFjsn/fTojU= X-Received: by 2002:a25:6644:: with SMTP id z4mr379569ybm.347.1601055414943; Fri, 25 Sep 2020 10:36:54 -0700 (PDT) MIME-Version: 1.0 References: <1600883188-4831-1-git-send-email-alan.maguire@oracle.com> <1600883188-4831-5-git-send-email-alan.maguire@oracle.com> <20200925005051.nqf6ru46psex7oh4@ast-mbp.dhcp.thefacebook.com> In-Reply-To: <20200925005051.nqf6ru46psex7oh4@ast-mbp.dhcp.thefacebook.com> From: Andrii Nakryiko Date: Fri, 25 Sep 2020 10:36:44 -0700 Message-ID: Subject: Re: [PATCH v6 bpf-next 4/6] selftests/bpf: add bpf_snprintf_btf helper tests To: Alexei Starovoitov Cc: Alan Maguire , Alexei Starovoitov , Daniel Borkmann , Andrii Nakryiko , Yonghong Song , Rasmus Villemoes , andriy.shevchenko@linux.intel.com, Petr Mladek , Martin Lau , Song Liu , john fastabend , KP Singh , Shuah Khan , Andrey Ignatov , scott.branden@broadcom.com, Quentin Monnet , Carlos Neira , Jakub Sitnicki , Ingo Molnar , Steven Rostedt , bpf , Networking , open list , "open list:KERNEL SELFTEST FRAMEWORK" , Arnaldo Carvalho de Melo Content-Type: text/plain; charset="UTF-8" Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org On Thu, Sep 24, 2020 at 5:51 PM Alexei Starovoitov wrote: > > On Wed, Sep 23, 2020 at 06:46:26PM +0100, Alan Maguire wrote: > > +static int __strncmp(const void *m1, const void *m2, size_t len) > > +{ > > + const unsigned char *s1 = m1; > > + const unsigned char *s2 = m2; > > + int i, delta = 0; > > + > > +#pragma clang loop unroll(full) > > Shouldn't be needed? > The verifier supports bounded loops. > > > + for (i = 0; i < len; i++) { > > + delta = s1[i] - s2[i]; > > + if (delta || s1[i] == 0 || s2[i] == 0) > > + break; > > + } > > + return delta; > > +} > > + > > +/* Use __builtin_btf_type_id to test snprintf_btf by type id instead of name */ > > +#if __has_builtin(__builtin_btf_type_id) > > +#define TEST_BTF_BY_ID(_str, _typestr, _ptr, _hflags) \ > > + do { \ > > + int _expected_ret = ret; \ > > + _ptr.type = 0; \ > > + _ptr.type_id = __builtin_btf_type_id(_typestr, 0); \ > > The test is passing for me, but I don't understand why :) > __builtin_btf_type_id(, 0); means btf_id of the bpf program. > While bpf_snprintf_btf() is treating it as btf_id of vmlinux_btf. > So it really should have been __builtin_btf_type_id(,1); Better still to use bpf_core_type_id_kernel() macro from bpf_core_read.h. > > The following diff works: > diff --git a/tools/testing/selftests/bpf/progs/netif_receive_skb.c b/tools/testing/selftests/bpf/progs/netif_receive_skb.c > index b4f96f1f6830..bffa786e3b03 100644 > --- a/tools/testing/selftests/bpf/progs/netif_receive_skb.c > +++ b/tools/testing/selftests/bpf/progs/netif_receive_skb.c > @@ -45,7 +45,7 @@ static int __strncmp(const void *m1, const void *m2, size_t len) > do { \ > int _expected_ret = ret; \ > _ptr.type = 0; \ > - _ptr.type_id = __builtin_btf_type_id(_typestr, 0); \ > + _ptr.type_id = __builtin_btf_type_id(_typestr, 1); \ > ret = bpf_snprintf_btf(_str, STRSIZE, &_ptr, \ > sizeof(_ptr), _hflags); \ > if (ret != _expected_ret) { \ > @@ -88,7 +88,7 @@ static int __strncmp(const void *m1, const void *m2, size_t len) > ret = -EBADMSG; \ > break; \ > } \ > - TEST_BTF_BY_ID(_str, #_type, _ptr, _hflags); \ > + TEST_BTF_BY_ID(_str, _ptr, _ptr, _hflags); \ > > But still makes me suspicious of the test. I haven't debugged further.