From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-wm1-f42.google.com (mail-wm1-f42.google.com [209.85.128.42]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id CD4D43B637A for ; Tue, 7 Apr 2026 12:59:26 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.128.42 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1775566768; cv=none; b=i7ilR5uul228ENc1fgHGB3eXFvuW+V96oTuacA7pD/KzGnTozEVk2TTyyOEjHrluEo/iPsd1/opOMIdW0djPFgHOJ1Qc9b/5uMLdNyUnyltGt5rL5kn69ZeLMNGjth+tZ9QHKM6l8I/IfPPwLG/Wfuzps9zjQefjsqIhFSazPdI= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1775566768; c=relaxed/simple; bh=ClqFDEJCQMCUYOkyBLnDQcgCM/IUjoTgXeAQm1kT/pU=; h=From:Date:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=cNTOeznG0uEICK19eWRA1CqQ2M6fvuFj1zqlPsmT/mEaATmBAw8NIvi5MozCJHpLW/nZBwmo3/jEPWW6wuns0Cpfvyc3LQyTGq3f8ot4WibYzIPrlGCy0qDkgnX5WG/Nn4pf54dTMKoS7+HZxcDIRIS+KCqNzDMHyuCqsXybY0o= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=gmail.com; spf=pass smtp.mailfrom=gmail.com; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b=BYGwn3qZ; arc=none smtp.client-ip=209.85.128.42 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=gmail.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=gmail.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="BYGwn3qZ" Received: by mail-wm1-f42.google.com with SMTP id 5b1f17b1804b1-48334ee0aeaso45729325e9.1 for ; Tue, 07 Apr 2026 05:59:26 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20251104; t=1775566765; x=1776171565; darn=vger.kernel.org; h=in-reply-to:content-disposition:mime-version:references:message-id :subject:cc:to:date:from:from:to:cc:subject:date:message-id:reply-to; bh=N4jBPWe3dTTt2wPLm8plPgxj5fmcSgMWAxKmxL7KXCM=; b=BYGwn3qZU+iYZWuVdWPVaEbabgbnQrMHYzDh8hgoOSMuiWkexHvoTnNXraHyY1P5Ka bg6POdMGdw8BGQGzpj7JAzsUUGqdjz88R9ryUmsBt8PvblbxyF7x667KAUFrEd/CDD7N MGwKjntEBXCgXMsNkiBXdA1LhYtZkobbYpC9ZOmCP55LNm0mz8nwy7i3kekm7kH7B5kq jk6h8PAKtDpYozmsvVOA3V2nRFPKA7oGsYzDAJmjCrwiG34/8qFg+Sfck/+cocejw2N4 0tIvtlCz+U0yLCD9jiLnuPofL09OB2S5u30NS9rU1rYFBV0aIcCLEmaz0ype/DiB4LUI HlPw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20251104; t=1775566765; x=1776171565; h=in-reply-to:content-disposition:mime-version:references:message-id :subject:cc:to:date:from:x-gm-gg:x-gm-message-state:from:to:cc :subject:date:message-id:reply-to; bh=N4jBPWe3dTTt2wPLm8plPgxj5fmcSgMWAxKmxL7KXCM=; b=SHzGpCb7MQ7Mn6pfsVwN4ETotIRq4lLOJHbndRzfheHjCr+js8zR6lRI/BMUgUYxiu +eVqo5LptDeHk+mTTuG3c4Ynw6qx8+G/lbgMxFWn4WcefU7oDddpmc7kObZVr8szrYyf kENPl6128opKtJu0EjHevTSoLDs0deDaO8jsXWGBk5uet+0pn/wbi4n1T6jdKwBLO0b2 zW24eZhZqXFRas1fiDZfkps4JAN1zVL5CLEUL0LAmydxXcjiWOlc0OLWQ2PQPp9yc2Gw np/ZuB1BLYdgMB26NRHloWlO5OUQ90VVAkYAryyVuTdxw2Gqzd1eiiuo+ltRO4comN49 v45w== X-Gm-Message-State: AOJu0YxsZK++p+9EpUpiv4CEvARe3oyW8vjyZhM3ybUfOzrZzCFCb3Uc f1OjEkXZi6i/IqEt4rCDtJWIWJdgvoXLLTLiZQNhjXd8L4HuAwCW/PNZ X-Gm-Gg: AeBDieuHBm0Rk1xPsh19879DSq+TcFQ5NiKLDgFVNEeKxdOmIrqpAfzi/Gzyh13JRJp l7mNY4XaXYA7xp0W4JDCT5QlQ/FUDQS6rT+VkmQ+QLWjSEmx32TSYs1FhS+CM4zythleSBmnG6f KFoFmMqs54HvgPzp6vf9odsTukhefbe1Qu5SGLHTs+JJ0ewMPiV3PrOwCq3BZBRA03UmaJShzvC VTIIKjOr7+GGZpIw54TggTD6tdNTSZJv9hoBTren8OvoW7iACb71pHCFWcGcCmJvpwUMvUUoRJy Ld0nUzUv0a3k7wxLXyT0q53joGue5KCjmx1Ef9bg23M29/HiKek61bBKeONdP0TQtDsHwjLH/bu 4uCpwLoboimR5isC2J7Fi3f+PW7wym5742j3raedj2zN1R6tiW9q8x29e87Bbgni0z+BBL/ikK4 c0GNvX+e0R7e8= X-Received: by 2002:a05:600c:6986:b0:487:2671:fb8f with SMTP id 5b1f17b1804b1-488996ecbf3mr211953095e9.8.1775566765013; Tue, 07 Apr 2026 05:59:25 -0700 (PDT) Received: from krava ([176.74.159.170]) by smtp.gmail.com with ESMTPSA id 5b1f17b1804b1-488a3d6944bsm280381005e9.11.2026.04.07.05.59.24 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 07 Apr 2026 05:59:24 -0700 (PDT) From: Jiri Olsa X-Google-Original-From: Jiri Olsa Date: Tue, 7 Apr 2026 14:59:23 +0200 To: Andrey Grodzovsky Cc: bpf@vger.kernel.org, linux-trace-kernel@vger.kernel.org, ast@kernel.org, daniel@iogearbox.net, andrii@kernel.org, rostedt@goodmis.org, mhiramat@kernel.org, ihor.solodrai@linux.dev, emil@etsalapatis.com, linux-open-source@crowdstrike.com Subject: Re: [RFC PATCH bpf-next v5 2/2] selftests/bpf: Add tests for duplicate kprobe symbol handling Message-ID: References: <20260406193158.754498-1-andrey.grodzovsky@crowdstrike.com> <20260406193158.754498-3-andrey.grodzovsky@crowdstrike.com> Precedence: bulk X-Mailing-List: bpf@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20260406193158.754498-3-andrey.grodzovsky@crowdstrike.com> On Mon, Apr 06, 2026 at 03:31:58PM -0400, Andrey Grodzovsky wrote: SNIP > +static void test_attach_probe_dup_sym(enum probe_attach_mode attach_mode) > +{ > + DECLARE_LIBBPF_OPTS(bpf_kprobe_opts, kprobe_opts); > + struct bpf_link *kprobe_link, *kretprobe_link; > + struct test_attach_probe_manual *skel; > + int err; > + > + /* Load module with duplicate symbol */ > + err = load_module("bpf_testmod_dup_sym.ko", false); > + if (!ASSERT_OK(err, "load_bpf_testmod_dup_sym")) { > + test__skip(); > + return; > + } > + > + skel = test_attach_probe_manual__open_and_load(); > + if (!ASSERT_OK_PTR(skel, "skel_dup_sym_open_and_load")) > + goto unload_module; > + > + /* manual-attach kprobe/kretprobe with duplicate symbol present */ > + kprobe_opts.attach_mode = attach_mode; > + kprobe_opts.retprobe = false; > + kprobe_link = bpf_program__attach_kprobe_opts(skel->progs.handle_kprobe, > + SYS_NANOSLEEP_KPROBE_NAME, > + &kprobe_opts); > + if (!ASSERT_OK_PTR(kprobe_link, "attach_kprobe_dup_sym")) > + goto cleanup; > + skel->links.handle_kprobe = kprobe_link; > + > + kprobe_opts.retprobe = true; > + kretprobe_link = bpf_program__attach_kprobe_opts(skel->progs.handle_kretprobe, > + SYS_NANOSLEEP_KPROBE_NAME, > + &kprobe_opts); maybe add tests for attaching the shadow module function as well? > diff --git a/tools/testing/selftests/bpf/test_kmods/bpf_testmod_dup_sym.c b/tools/testing/selftests/bpf/test_kmods/bpf_testmod_dup_sym.c > new file mode 100644 > index 000000000000..0e12f68afe3a > --- /dev/null > +++ b/tools/testing/selftests/bpf/test_kmods/bpf_testmod_dup_sym.c > @@ -0,0 +1,48 @@ > +// SPDX-License-Identifier: GPL-2.0 > +/* Copyright (c) 2025 CrowdStrike */ > +/* Test module for duplicate kprobe symbol handling */ > +#include > +#include > +#include > + > +/* Duplicate symbol to test kprobe attachment with duplicate symbols. > + * This creates a duplicate of the syscall wrapper used in attach_probe tests. > + * The libbpf fix should handle this by preferring the vmlinux symbol. > + * This function should NEVER be called - kprobes should attach to vmlinux version. > + */ > +#ifdef __x86_64__ > +int __x64_sys_nanosleep(void); > +noinline int __x64_sys_nanosleep(void) > +#elif defined(__s390x__) > +int __s390x_sys_nanosleep(void); > +noinline int __s390x_sys_nanosleep(void) > +#elif defined(__aarch64__) > +int __arm64_sys_nanosleep(void); > +noinline int __arm64_sys_nanosleep(void) > +#elif defined(__riscv) > +int __riscv_sys_nanosleep(void); > +noinline int __riscv_sys_nanosleep(void) > +#else > +int sys_nanosleep(void); > +noinline int sys_nanosleep(void) > +#endif could we use module_fentry_shadow instead? it's in kernel and in bpf_testmod for fentry shadowing test.. it's not executed via test_run but it could be added or we just don't run it jirka > +{ > + WARN_ONCE(1, "bpf_testmod_dup_sym: dummy nanosleep symbol called - this should never execute!\n"); > + return -EINVAL; > +} > + > +static int __init bpf_testmod_dup_sym_init(void) > +{ > + return 0; > +} > + > +static void __exit bpf_testmod_dup_sym_exit(void) > +{ > +} > + > +module_init(bpf_testmod_dup_sym_init); > +module_exit(bpf_testmod_dup_sym_exit); > + > +MODULE_AUTHOR("Andrey Grodzovsky"); > +MODULE_DESCRIPTION("BPF selftest duplicate symbol module"); > +MODULE_LICENSE("GPL"); > -- > 2.34.1 >