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=-12.7 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=unavailable 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 9B142C433DB for ; Tue, 2 Mar 2021 10:38:35 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 4BE0764F07 for ; Tue, 2 Mar 2021 10:38:35 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1380073AbhCBK2t (ORCPT ); Tue, 2 Mar 2021 05:28:49 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:56662 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S239800AbhCBAf0 (ORCPT ); Mon, 1 Mar 2021 19:35:26 -0500 Received: from mail-yb1-xb31.google.com (mail-yb1-xb31.google.com [IPv6:2607:f8b0:4864:20::b31]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 6C1A9C06178C; Mon, 1 Mar 2021 16:34:36 -0800 (PST) Received: by mail-yb1-xb31.google.com with SMTP id p193so18931071yba.4; Mon, 01 Mar 2021 16:34:36 -0800 (PST) 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=F9VmOYR1Qo8kLJcpDxdviInMt3+/uSHxCcs+aiiYM2c=; b=X7YUNY3F4iEqnr4AZc5K+wpIudTH4atG9R1PleILcziU6gJCYTUvP5lPeTje9iltCa Ols/FnqXdc/Tc6izRqk2jazJRQCVyN6/L+zjrLKE68+uxQUnJZvPE4zEpcIIvfwuYl86 N+SjdGZs4jc/suVIScf69laUZAV3Bsb2MNatSxj1qm6SwHfD3wH7uYTySIdGfQXhfgv2 LIt7H+sjZfi1j1CwFF87RM6LXE02ggkIH487pGwbwSD6zvZImeKBpdoOizOR0B7TTNIe PbqnPEfPfQx64hwV9wcdbEULlmRNoXsTIfTZ6OhXSqbmi3D8o20G7cfXhkzYj1GZ65GS 49TQ== 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=F9VmOYR1Qo8kLJcpDxdviInMt3+/uSHxCcs+aiiYM2c=; b=JbjSNx0pevzkPX6azk51kKv4YrqXk/0wsf3jbQ17vbDYmlQi+FCmBrovSBTElYWBfL gndn4QrnKSZhA5+Akj3oitLTZWKNUh8/ruvkI5d+Hb4Y7EpUNZeULejZjtcjAbnktxz0 HgLFDvCPIcaUhD/SiqIPdHCORqK4AauWrLD0muGLTZaU4DdbCTyxCCvjCkdcWoYPX/W+ NA3xGublhCemIO/pRfS+q6RYxBy0Q86VOxtKkGBkBmFdtDhD5l8J9VTdoPUPdjua8aqA 14dp81tjZ8HcOnOGd6reqBEF02zEbqJDzLVdzCFVlqAdh2rIRvQw2MAdwWaMYnid5//D 4iXA== X-Gm-Message-State: AOAM532nSRqRQuDDwP2fTyRRqQzT0IAlyFMWP60hZ8r+SaeXTV9syNX7 AgiHcHGzLoI5C4IRXXHC6bevpWW4XojaS4xATlA= X-Google-Smtp-Source: ABdhPJx98q2KCRQ3je/TnWHPYP38n6lQwWpPlRpj++ZJ8GKGySO18UA1V4ZXnlAHUgfD3mE7TPKYIDmiFjUdFeDZ5uc= X-Received: by 2002:a25:bd12:: with SMTP id f18mr27907808ybk.403.1614645275613; Mon, 01 Mar 2021 16:34:35 -0800 (PST) MIME-Version: 1.0 References: <20210301190416.90694-1-jolsa@kernel.org> In-Reply-To: <20210301190416.90694-1-jolsa@kernel.org> From: Andrii Nakryiko Date: Mon, 1 Mar 2021 16:34:24 -0800 Message-ID: Subject: Re: [PATCH bpf-next] selftests/bpf: Fix test_attach_probe for powerpc uprobes To: Jiri Olsa Cc: Alexei Starovoitov , Daniel Borkmann , Andrii Nakryiko , Networking , bpf , Martin KaFai Lau , Song Liu , Yonghong Song , John Fastabend , KP Singh , =?UTF-8?B?VG9rZSBIw7hpbGFuZC1Kw7hyZ2Vuc2Vu?= , Yauheni Kaliuta Content-Type: text/plain; charset="UTF-8" Precedence: bulk List-ID: X-Mailing-List: bpf@vger.kernel.org On Mon, Mar 1, 2021 at 11:11 AM Jiri Olsa wrote: > > When testing uprobes we the test gets GEP (Global Entry Point) > address from kallsyms, but then the function is called locally > so the uprobe is not triggered. > > Fixing this by adjusting the address to LEP (Local Entry Point) > for powerpc arch. > > Signed-off-by: Jiri Olsa > --- > .../selftests/bpf/prog_tests/attach_probe.c | 18 +++++++++++++++++- > 1 file changed, 17 insertions(+), 1 deletion(-) > > diff --git a/tools/testing/selftests/bpf/prog_tests/attach_probe.c b/tools/testing/selftests/bpf/prog_tests/attach_probe.c > index a0ee87c8e1ea..c3cfb48d3ed0 100644 > --- a/tools/testing/selftests/bpf/prog_tests/attach_probe.c > +++ b/tools/testing/selftests/bpf/prog_tests/attach_probe.c > @@ -2,6 +2,22 @@ > #include > #include "test_attach_probe.skel.h" > > +#if defined(__powerpc64__) > +/* > + * We get the GEP (Global Entry Point) address from kallsyms, > + * but then the function is called locally, so we need to adjust > + * the address to get LEP (Local Entry Point). > + */ > +#define LEP_OFFSET 8 > + > +static ssize_t get_offset(ssize_t offset) if we mark this function __weak global, would it work as is? Would it get an address of a global entry point? I know nothing about this GEP vs LEP stuff, interesting :) > +{ > + return offset + LEP_OFFSET; > +} > +#else > +#define get_offset(offset) (offset) > +#endif > + > ssize_t get_base_addr() { > size_t start, offset; > char buf[256]; > @@ -36,7 +52,7 @@ void test_attach_probe(void) > if (CHECK(base_addr < 0, "get_base_addr", > "failed to find base addr: %zd", base_addr)) > return; > - uprobe_offset = (size_t)&get_base_addr - base_addr; > + uprobe_offset = get_offset((size_t)&get_base_addr - base_addr); > > skel = test_attach_probe__open_and_load(); > if (CHECK(!skel, "skel_open", "failed to open skeleton\n")) > -- > 2.29.2 >