From nobody Thu Apr 2 14:08:58 2026 Received: from mail-ej1-f43.google.com (mail-ej1-f43.google.com [209.85.218.43]) (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 E79A233A9F5 for ; Sat, 28 Mar 2026 14:58:19 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.218.43 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1774709901; cv=none; b=aKw5ew6bLu0lLEem9LVtHS6MZhBQ1Gjb2JXFb+1l3ZZ+47iQQ8DwhfS1yFSx8fsyR4Q4iu5D5J7wER1Erx+qqnTsQjblI0w05ygtRNgOBjwLAaURN8sCiWPEkA9t0TyvOSfQU+hBiU+ahTQUcEJfmPCM373D5r+8H+g6wl0YWTw= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1774709901; c=relaxed/simple; bh=yL8Td9UZA88O3o7r3JW+BpHaCJ4yxltbSa4UhiL9gIg=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=jHEonIngMmL0tinlNK83/KU2hzgY1/w7r8MO/yMbY2mzg7B/ptoefw69M4+orZF4xfn4TebIaJYdP/esKcpVTsrzPGgUq/P1g/bmN8fLmP1iak25wsD1iAi9MS/823KKFVKG0vaiyNhsO7242Jkv7SeHUh42RoFmvl8XUyC7Na0= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=suse.com; spf=pass smtp.mailfrom=suse.com; dkim=pass (2048-bit key) header.d=suse.com header.i=@suse.com header.b=QyrAvXy0; arc=none smtp.client-ip=209.85.218.43 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=suse.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=suse.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=suse.com header.i=@suse.com header.b="QyrAvXy0" Received: by mail-ej1-f43.google.com with SMTP id a640c23a62f3a-b93698bb57aso564109166b.0 for ; Sat, 28 Mar 2026 07:58:19 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=suse.com; s=google; t=1774709862; x=1775314662; darn=vger.kernel.org; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:from:to:cc:subject:date :message-id:reply-to; bh=lPuSW6pRsFeFjtweuNOAKbGLGRJBOpgP+7O/NYd7b34=; b=QyrAvXy0tMZOgQRPGNQ0fBzw9RhSSDxLbR//G2z2hWtClO4dq5iZ6/KTdfK3cR2LbF oMTrg4D1yywpjC7r7tnwaXI7XLLlIAPYWlWbz+nyFrwS0aZ9qL1G1Mirw92XuS9FMem1 rThQZQ89lNwhan9UudIcO3RbCT+xwhG6gdlIRrt1wohxZ1yNbuzgpYMfHcxjNDNPofKK SSbkO6IbhZKpoI2778jjNxYR3HpB3GKDd187Ae7KjWYiOQrIZB0HYpce3qAfwl+f6FaJ uecKGEpXoTNuTEg9l5l+HpzU7gvqOs/U9749ulfUbBkbewKaFXBLjD32EYO/gAVgaowD dxmQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20251104; t=1774709862; x=1775314662; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:x-gm-gg:x-gm-message-state:from :to:cc:subject:date:message-id:reply-to; bh=lPuSW6pRsFeFjtweuNOAKbGLGRJBOpgP+7O/NYd7b34=; b=juHp2xEBZDKQHqaEmaI5EtxYoEZmwUmIpTWfODGlskmrooXOnBI0uAjViJdrOqnrUU jBPIoMipjBW+0JhGZryrYKogBVmb3ZIsJaqPbO5wMwxBLuiArnWiutWGlix4mzTOurja dc5OWE2Etazq1oXoFqEqr/GO+NodJsj7XR5szsDyc/EynKnUIGplX6TJYytm320cUO2a llj9Ht8VsIfleWirBrLs4zl8zrHJD/VvTlaC22q+pG9yAPPQ8/hvYkbFOfdwHW5gjaKq qiNC2vZGGtHMtlICLq8dKGw5yOPQSC7ElyFCV5TxHLS6AbRhwWbCpIzdbAl2qY2Pl+qB YFLw== X-Forwarded-Encrypted: i=1; AJvYcCVZE29UeDfG9T/QjOfLhmjtH7t8pHNQNwbvy1F7x+Oj4lzUNKfw7JmQiXiitBT7JW8oIZVMYazezNACiT8=@vger.kernel.org X-Gm-Message-State: AOJu0YwuKpPY4BRwcj5UuMQbVaSukLfbDZpnY3nIyrp8OxSHoJ3A08Ne Hy/nrYjS1bWXuXxg00jLfGVmraTtxWmgtzxGYraHs7wc2zMb3Ly7OV7zqQW5liizIBc= X-Gm-Gg: ATEYQzyPbLx/EENcizHkkoeIY8fH6Re5ojb799RCqLa7Bs9YBUiHpcOLI7VulkZZxv4 uczUJm4m0HYspUK887kLOUh9BPdu+m770GI/9vuU5bbeyTfupP4KJ5PVKWCzxCCwuaA92ibbVeW aFyLeyk0I9xXQmz54mJajE8vcorVxm5C3LrdwGCpvwvurO70V2Qc+0l0ZvDZ6MdC9y4oVfKCskA 0qm5O9PDXaj6nTQ4yOwEZaD2bF7knqTCbt2vpoW6iUYzR66sWh2ym/Hwryb9QLGCiFSdlzG930R 4y9uQNtrZsjrbq+x6yv01KHM0D5efKA5I+E4dyDxeNMN118iHQun2KxdWckPoLlCzc3rcxNa4Wy Bfnf/tK3ipo6gt3NWYC+fko75AX0qQhri4Cs6pGfVZkPzAajbxlEba57OMRP0j2O/IxmYCEj6BV PjNW+YjdPDlt7Qydvrl3IlwMnP809f6eNopu0I5GDu1jwQ3PDutTwud9U4vIXBNrdRDhgOvSzH X-Received: by 2002:a05:600c:5956:b0:486:fe08:639a with SMTP id 5b1f17b1804b1-48722b813a4mr110789345e9.4.1774708012383; Sat, 28 Mar 2026 07:26:52 -0700 (PDT) Received: from f16.localdomain ([121.167.230.140]) by smtp.gmail.com with ESMTPSA id 41be03b00d2f7-c76916da892sm1874017a12.14.2026.03.28.07.26.49 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Sat, 28 Mar 2026 07:26:51 -0700 (PDT) From: Hoyeon Lee To: bpf@vger.kernel.org, Alexei Starovoitov , Daniel Borkmann , Andrii Nakryiko , Martin KaFai Lau Cc: Eduard Zingerman , Kumar Kartikeya Dwivedi , Song Liu , Yonghong Song , Jiri Olsa , Shuah Khan , Feng Yang , linux-kselftest@vger.kernel.org, linux-kernel@vger.kernel.org Subject: [PATCH bpf-next 1/2] libbpf: allow address-based single kprobe attach Date: Sat, 28 Mar 2026 23:26:08 +0900 Message-ID: <20260328142643.627560-2-hoyeon.lee@suse.com> X-Mailer: git-send-email 2.52.0 In-Reply-To: <20260328142643.627560-1-hoyeon.lee@suse.com> References: <20260328142643.627560-1-hoyeon.lee@suse.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="utf-8" bpf_program__attach_kprobe_opts() currently attaches a single kprobe only by func_name, with an optional offset. This covers only the symbol- based form, not the raw-address form that the kernel already supports for both kprobe PMU events and legacy tracefs/debugfs kprobes. Callers that already have a target IP still have to drop down to perf_event_open() or direct tracefs writes. libbpf already exposes address-based attach for kprobe_multi through bpf_kprobe_multi_opts.addrs. This commit adds bpf_kprobe_opts.addr so that single kprobes can be attached either by func_name + offset or by raw address. Signed-off-by: Hoyeon Lee --- tools/lib/bpf/libbpf.c | 77 +++++++++++++++++++++++++++++------------- tools/lib/bpf/libbpf.h | 5 ++- 2 files changed, 57 insertions(+), 25 deletions(-) diff --git a/tools/lib/bpf/libbpf.c b/tools/lib/bpf/libbpf.c index 9ea41f40dc82..a49ea01288ad 100644 --- a/tools/lib/bpf/libbpf.c +++ b/tools/lib/bpf/libbpf.c @@ -11523,7 +11523,7 @@ static int determine_uprobe_retprobe_bit(void) #define PERF_UPROBE_REF_CTR_OFFSET_SHIFT 32 =20 static int perf_event_open_probe(bool uprobe, bool retprobe, const char *n= ame, - uint64_t offset, int pid, size_t ref_ctr_off) + uint64_t offset_or_addr, int pid, size_t ref_ctr_off) { const size_t attr_sz =3D sizeof(struct perf_event_attr); struct perf_event_attr attr; @@ -11558,7 +11558,7 @@ static int perf_event_open_probe(bool uprobe, bool = retprobe, const char *name, attr.type =3D type; attr.config |=3D (__u64)ref_ctr_off << PERF_UPROBE_REF_CTR_OFFSET_SHIFT; attr.config1 =3D ptr_to_u64(name); /* kprobe_func or uprobe_path */ - attr.config2 =3D offset; /* kprobe_addr or probe_offset */ + attr.config2 =3D offset_or_addr; /* kprobe_addr or probe_offset */ =20 /* pid filter is meaningful only for uprobes */ pfd =3D syscall(__NR_perf_event_open, &attr, @@ -11633,13 +11633,14 @@ static const char *tracefs_available_filter_funct= ions_addrs(void) } =20 static void gen_probe_legacy_event_name(char *buf, size_t buf_sz, - const char *name, size_t offset) + const char *name, uint64_t offset_or_addr) { static int index =3D 0; int i; =20 - snprintf(buf, buf_sz, "libbpf_%u_%d_%s_0x%zx", getpid(), - __sync_fetch_and_add(&index, 1), name, offset); + snprintf(buf, buf_sz, "libbpf_%u_%d_%s_0x%" PRIx64, getpid(), + __sync_fetch_and_add(&index, 1), name ?: "addr", + offset_or_addr); =20 /* sanitize name in the probe name */ for (i =3D 0; buf[i]; i++) { @@ -11648,13 +11649,27 @@ static void gen_probe_legacy_event_name(char *buf= , size_t buf_sz, } } =20 +static void gen_kprobe_target(char *buf, size_t buf_sz, const char *name, + uint64_t offset_or_addr) +{ + if (name) + snprintf(buf, buf_sz, "%s+0x%" PRIx64, name, offset_or_addr); + else + snprintf(buf, buf_sz, "0x%" PRIx64, offset_or_addr); +} + static int add_kprobe_event_legacy(const char *probe_name, bool retprobe, - const char *kfunc_name, size_t offset) + const char *kfunc_name, uint64_t offset_or_addr) { - return append_to_file(tracefs_kprobe_events(), "%c:%s/%s %s+0x%zx", + char probe_target[128]; + + gen_kprobe_target(probe_target, sizeof(probe_target), kfunc_name, + offset_or_addr); + + return append_to_file(tracefs_kprobe_events(), "%c:%s/%s %s", retprobe ? 'r' : 'p', retprobe ? "kretprobes" : "kprobes", - probe_name, kfunc_name, offset); + probe_name, probe_target); } =20 static int remove_kprobe_event_legacy(const char *probe_name, bool retprob= e) @@ -11674,24 +11689,27 @@ static int determine_kprobe_perf_type_legacy(cons= t char *probe_name, bool retpro } =20 static int perf_event_kprobe_open_legacy(const char *probe_name, bool retp= robe, - const char *kfunc_name, size_t offset, int pid) + const char *kfunc_name, uint64_t offset_or_addr, int pid) { const size_t attr_sz =3D sizeof(struct perf_event_attr); struct perf_event_attr attr; int type, pfd, err; + char probe_target[128]; =20 - err =3D add_kprobe_event_legacy(probe_name, retprobe, kfunc_name, offset); + gen_kprobe_target(probe_target, sizeof(probe_target), kfunc_name, + offset_or_addr); + + err =3D add_kprobe_event_legacy(probe_name, retprobe, kfunc_name, + offset_or_addr); if (err < 0) { - pr_warn("failed to add legacy kprobe event for '%s+0x%zx': %s\n", - kfunc_name, offset, + pr_warn("failed to add legacy kprobe event for '%s': %s\n", probe_target, errstr(err)); return err; } type =3D determine_kprobe_perf_type_legacy(probe_name, retprobe); if (type < 0) { err =3D type; - pr_warn("failed to determine legacy kprobe event id for '%s+0x%zx': %s\n= ", - kfunc_name, offset, + pr_warn("failed to determine legacy kprobe event id for '%s': %s\n", pro= be_target, errstr(err)); goto err_clean_legacy; } @@ -11784,6 +11802,9 @@ bpf_program__attach_kprobe_opts(const struct bpf_pr= ogram *prog, enum probe_attach_mode attach_mode; char *legacy_probe =3D NULL; struct bpf_link *link; + uint64_t offset_or_addr; + char probe_target[128]; + unsigned long addr; size_t offset; bool retprobe, legacy; int pfd, err; @@ -11794,8 +11815,18 @@ bpf_program__attach_kprobe_opts(const struct bpf_p= rogram *prog, attach_mode =3D OPTS_GET(opts, attach_mode, PROBE_ATTACH_MODE_DEFAULT); retprobe =3D OPTS_GET(opts, retprobe, false); offset =3D OPTS_GET(opts, offset, 0); + addr =3D OPTS_GET(opts, addr, 0); + offset_or_addr =3D func_name ? offset : addr; pe_opts.bpf_cookie =3D OPTS_GET(opts, bpf_cookie, 0); =20 + if (!!func_name =3D=3D !!addr) + return libbpf_err_ptr(-EINVAL); + if (addr && offset) + return libbpf_err_ptr(-EINVAL); + + gen_kprobe_target(probe_target, sizeof(probe_target), func_name, + offset_or_addr); + legacy =3D determine_kprobe_perf_type() < 0; switch (attach_mode) { case PROBE_ATTACH_MODE_LEGACY: @@ -11819,26 +11850,25 @@ bpf_program__attach_kprobe_opts(const struct bpf_= program *prog, =20 if (!legacy) { pfd =3D perf_event_open_probe(false /* uprobe */, retprobe, - func_name, offset, + func_name, offset_or_addr, -1 /* pid */, 0 /* ref_ctr_off */); } else { char probe_name[MAX_EVENT_NAME_LEN]; =20 gen_probe_legacy_event_name(probe_name, sizeof(probe_name), - func_name, offset); + func_name, offset_or_addr); =20 legacy_probe =3D strdup(probe_name); if (!legacy_probe) return libbpf_err_ptr(-ENOMEM); =20 pfd =3D perf_event_kprobe_open_legacy(legacy_probe, retprobe, func_name, - offset, -1 /* pid */); + offset_or_addr, -1 /* pid */); } if (pfd < 0) { - err =3D -errno; - pr_warn("prog '%s': failed to create %s '%s+0x%zx' perf event: %s\n", - prog->name, retprobe ? "kretprobe" : "kprobe", - func_name, offset, + err =3D pfd; + pr_warn("prog '%s': failed to create %s '%s' perf event: %s\n", + prog->name, retprobe ? "kretprobe" : "kprobe", probe_target, errstr(err)); goto err_out; } @@ -11846,9 +11876,8 @@ bpf_program__attach_kprobe_opts(const struct bpf_pr= ogram *prog, err =3D libbpf_get_error(link); if (err) { close(pfd); - pr_warn("prog '%s': failed to attach to %s '%s+0x%zx': %s\n", - prog->name, retprobe ? "kretprobe" : "kprobe", - func_name, offset, + pr_warn("prog '%s': failed to attach to %s '%s': %s\n", + prog->name, retprobe ? "kretprobe" : "kprobe", probe_target, errstr(err)); goto err_clean_legacy; } diff --git a/tools/lib/bpf/libbpf.h b/tools/lib/bpf/libbpf.h index 0be34852350f..526d44111e81 100644 --- a/tools/lib/bpf/libbpf.h +++ b/tools/lib/bpf/libbpf.h @@ -563,9 +563,12 @@ struct bpf_kprobe_opts { bool retprobe; /* kprobe attach mode */ enum probe_attach_mode attach_mode; + /* kernel address to install kprobe to; mutually exclusive with func_name= */ + unsigned long addr; size_t :0; }; -#define bpf_kprobe_opts__last_field attach_mode + +#define bpf_kprobe_opts__last_field addr =20 LIBBPF_API struct bpf_link * bpf_program__attach_kprobe(const struct bpf_program *prog, bool retprobe, --=20 2.52.0 From nobody Thu Apr 2 14:08:58 2026 Received: from mail-lj1-f179.google.com (mail-lj1-f179.google.com [209.85.208.179]) (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 A293C2DB78C for ; Sat, 28 Mar 2026 15:40:34 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.208.179 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1774712436; cv=none; b=lm/KztBSVZ86ONgpqVjH86vywrSNq3NcteEfi4lqkjr3HjsUwjWZflPDxdprnkupqCBu/FPN6KO4UoyEh4eOLYfFxvhAGnEhSv5o7AUZhHmrK0gOIF1pYnG6JochsPVesV4rfFqcrS2jh8yHuemX2ocRNIaw7aXK+nGbJLmz8ck= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1774712436; c=relaxed/simple; bh=+JvJUtFV1FwOAyBEZih9NfIXAfatfUjyA2bfmrJIeeY=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=gFp59Wk6tQvOq6cYbcM2BboTMiF9Zinf26i6p8l43DPyJlgRdRa+B8x75/XVJpDVTTWczLBSFfTnxzBkHrmbDWJF5+/UKyoO/ktFjwcAbFJP+dcrEKWC5Kh97YkRIIguoLqf0mvMLW6lzmTd248giYd+kGDBS9fJHh857CZiVPo= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=suse.com; spf=pass smtp.mailfrom=suse.com; dkim=pass (2048-bit key) header.d=suse.com header.i=@suse.com header.b=HasvYFLP; arc=none smtp.client-ip=209.85.208.179 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=suse.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=suse.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=suse.com header.i=@suse.com header.b="HasvYFLP" Received: by mail-lj1-f179.google.com with SMTP id 38308e7fff4ca-38bf1561215so17388321fa.2 for ; Sat, 28 Mar 2026 08:40:34 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=suse.com; s=google; t=1774712433; x=1775317233; darn=vger.kernel.org; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:from:to:cc:subject:date :message-id:reply-to; bh=CnDYuCPPOC0a7dKZYCydLNtXkl+EJ9KEblo4sLyQOoE=; b=HasvYFLPzSEmBeMWGLGdm+bshiP29ZWnuO708GvASra3wL4XRXc4BPpZVMDGZ65ZGS tMNb8VsyNznwKvkBo0psj8axjQW8JFSNRK+GM3PhdEa85nNrWUG0izhv/HoyBkDojxoN T9l00QlUb6QH56P162i/ihNFPmcgQr7OTUHHH0WZsG8W5Dfq8S8bfj4CzkAuGR9L0wxi 06LgIJLT9yB+qAZorcS91WkGpzeDCrJWUkg8RiaFE21q3WR9xjSRy1g/MiQb4ALaYLtK C3VBbLe24y7YGiQwcmx/qwz9eqQwzECOpA7Oy6VYHCvZq8fzocyqDmxeSS/J77c9IOa+ wTVw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20251104; t=1774712433; x=1775317233; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:x-gm-gg:x-gm-message-state:from :to:cc:subject:date:message-id:reply-to; bh=CnDYuCPPOC0a7dKZYCydLNtXkl+EJ9KEblo4sLyQOoE=; b=YfHjQ2G5GW8VVQxcIojP0VYPy6Sq6F+UVctxn0KfoxKRGESYs2xTb4Qwt3dSy2B8tf tN3DX6mVppnFdYje4nZloJEA5KFE1Pk44D37CdxwRjTS4r0HTyMNUx/UDsrgGWdGs2AJ gC87SnLNTd8+eJy1WSpZtaT1fOvcmblWtya2dbzQqC0IYkNxAbVX8U3NDLk93roGZthu zIvbweFfk27ReK+XFKAX0RWxCAYGwUE92Y6A+8cmyPMkGTyrbxXM/4vBcd3rb9ldHSzC MMlLqRKn1ISAUYLtO/6UMp0buWRyjaWluyqLiOQAkfdQ/K20DH4zyHhFS6qh9MoDqdfB Vc+w== X-Forwarded-Encrypted: i=1; AJvYcCXDjdt/LY0gfRzVi4r0sR79/Z1rczb5H5P0kpP5EHxc5AoVYqavyp7+GgYdl4HF/bZVTHpl6fEanDgqs/s=@vger.kernel.org X-Gm-Message-State: AOJu0YxF0eA+vFRHLh3zUcjps6S07WxA3G6XZMrXwIxydp179svvGJZJ t1jM4KvVR/y2SRFLTG7lN//07ifx3vOr69vWgvMQZ9ABkW1VBzGMI4IguMpMeO16ZZD3Wf+QiVk XR4ZBezA= X-Gm-Gg: ATEYQzxOfXgCdpVFQ12DVFrv24KigK1KYhCDYdotGbYpknvAHEV/o/eBtEP5OWzvyVn p4TP/UFT5vLL31xpR4+vU1KRoXlRGX9/X25TYlac6R3hg+L3X3tdJUR2ZNc5BLEXngfVHscTNrz qLnSe1HAvM8RL5igwKwAkNHK4SMQGc0aDqWwK7NU/hntEVx8zPrwyZ5rZqQ/N2LJzJgBdOsKKwr 4X46TULVpsv6hbY8MWzTQSng3pL6k05GKqDTyOE4D2/xAoULZBL/14oB2FnYmu3bRibqOwigIBX neWrg+o49+X4gn8T77c5lx+Qh+JGAiSU/LR7jdpIJbDN6JYMXqkHBOIiioCba0W/i7rcZb5VSDE vgUaHRpWuEio1u2tB2dAe7EFs94oSaQe1ayX6Zz7GITJKzwotf1n+z0fokxIymr8gX+ndREeCIT /SXWSNyy2UVZL0O54BeUL3qXQ1WjVTx33traDm0/n9c06IHSHjZpSSPBW3zHVH8w== X-Received: by 2002:a05:600d:1c:b0:485:3f17:425 with SMTP id 5b1f17b1804b1-48727ec7681mr82529125e9.21.1774708015839; Sat, 28 Mar 2026 07:26:55 -0700 (PDT) Received: from f16.localdomain ([121.167.230.140]) by smtp.gmail.com with ESMTPSA id 41be03b00d2f7-c76916da892sm1874017a12.14.2026.03.28.07.26.52 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Sat, 28 Mar 2026 07:26:54 -0700 (PDT) From: Hoyeon Lee To: bpf@vger.kernel.org, Alexei Starovoitov , Daniel Borkmann , Andrii Nakryiko , Martin KaFai Lau Cc: Eduard Zingerman , Kumar Kartikeya Dwivedi , Song Liu , Yonghong Song , Jiri Olsa , Shuah Khan , Feng Yang , linux-kselftest@vger.kernel.org, linux-kernel@vger.kernel.org Subject: [PATCH bpf-next 2/2] selftests/bpf: add test for address-based single kprobe attach Date: Sat, 28 Mar 2026 23:26:09 +0900 Message-ID: <20260328142643.627560-3-hoyeon.lee@suse.com> X-Mailer: git-send-email 2.52.0 In-Reply-To: <20260328142643.627560-1-hoyeon.lee@suse.com> References: <20260328142643.627560-1-hoyeon.lee@suse.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="utf-8" attach_probe already verifies manual single-kprobe attaches with func_name and optional offset. This commit adds address-based single-kprobe attach subtests for the two underlying attach paths, legacy tracefs/debugfs and PMU-based non-legacy. The new subtests resolve SYS_NANOSLEEP_KPROBE_NAME through kallsyms, pass the result through bpf_kprobe_opts.addr, and verify that kprobe and kretprobe are still triggered. Signed-off-by: Hoyeon Lee --- .../selftests/bpf/prog_tests/attach_probe.c | 49 +++++++++++++++++++ 1 file changed, 49 insertions(+) diff --git a/tools/testing/selftests/bpf/prog_tests/attach_probe.c b/tools/= testing/selftests/bpf/prog_tests/attach_probe.c index 9e77e5da7097..64f2ed75779d 100644 --- a/tools/testing/selftests/bpf/prog_tests/attach_probe.c +++ b/tools/testing/selftests/bpf/prog_tests/attach_probe.c @@ -123,6 +123,51 @@ static void test_attach_probe_manual(enum probe_attach= _mode attach_mode) test_attach_probe_manual__destroy(skel); } =20 +/* manual attach address-based kprobe/kretprobe testings */ +static void test_attach_kprobe_by_addr(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; + unsigned long func_addr; + + if (!ASSERT_OK(load_kallsyms(), "load_kallsyms")) + return; + + func_addr =3D ksym_get_addr(SYS_NANOSLEEP_KPROBE_NAME); + if (!ASSERT_NEQ(func_addr, 0UL, "func_addr")) + return; + + skel =3D test_attach_probe_manual__open_and_load(); + if (!ASSERT_OK_PTR(skel, "skel_kprobe_manual_open_and_load")) + return; + + kprobe_opts.attach_mode =3D attach_mode; + kprobe_opts.retprobe =3D false; + kprobe_opts.addr =3D func_addr; + kprobe_link =3D bpf_program__attach_kprobe_opts(skel->progs.handle_kprobe, + NULL, &kprobe_opts); + if (!ASSERT_OK_PTR(kprobe_link, "attach_kprobe_by_addr")) + goto cleanup; + skel->links.handle_kprobe =3D kprobe_link; + + kprobe_opts.retprobe =3D true; + kretprobe_link =3D bpf_program__attach_kprobe_opts(skel->progs.handle_kre= tprobe, + NULL, &kprobe_opts); + if (!ASSERT_OK_PTR(kretprobe_link, "attach_kretprobe_by_addr")) + goto cleanup; + skel->links.handle_kretprobe =3D kretprobe_link; + + /* trigger & validate kprobe && kretprobe */ + usleep(1); + + ASSERT_EQ(skel->bss->kprobe_res, 1, "check_kprobe_res"); + ASSERT_EQ(skel->bss->kretprobe_res, 2, "check_kretprobe_res"); + +cleanup: + test_attach_probe_manual__destroy(skel); +} + /* attach uprobe/uretprobe long event name testings */ static void test_attach_uprobe_long_event_name(void) { @@ -416,6 +461,10 @@ void test_attach_probe(void) test_attach_probe_manual(PROBE_ATTACH_MODE_PERF); if (test__start_subtest("manual-link")) test_attach_probe_manual(PROBE_ATTACH_MODE_LINK); + if (test__start_subtest("kprobe-legacy-by-addr")) + test_attach_kprobe_by_addr(PROBE_ATTACH_MODE_LEGACY); + if (test__start_subtest("kprobe-perf-by-addr")) + test_attach_kprobe_by_addr(PROBE_ATTACH_MODE_PERF); =20 if (test__start_subtest("auto")) test_attach_probe_auto(skel); --=20 2.52.0