From nobody Mon Dec 15 21:42:45 2025 Received: from out-183.mta1.migadu.com (out-183.mta1.migadu.com [95.215.58.183]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 23A81266B55 for ; Mon, 24 Feb 2025 17:00:10 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=95.215.58.183 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1740416413; cv=none; b=LSObtbaO1ImCFHEesG2dJhQRe3A64h2YnMmQrhFkXcycHPd+L7gw+mHQVDdSaYKbml833yhgsIMfo7eJO5SwoCl/JILh8zvv+yHzBBCpidEJ8NIHpWk62WaWorD2tlICEYj4o0YpGXVK3VNP5KytqliujmDNyZZ8rIr0KZr5uDQ= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1740416413; c=relaxed/simple; bh=jm9V/uGdHxg5OBS/aN+olvdgGrxxL3p39+/oZgyyRrw=; h=From:To:Cc:Subject:Date:Message-Id:In-Reply-To:References: MIME-Version; b=oD5KLDNqnZhrln8epXifyOa8ZHfkioBgJ0Uokll5hfK74H3J4JOVbuAzfiVYIVIVG4VIZdNoOV0kcT5FPcc4kNTk5r0Jcn269t6uGaa2Azrbl9h+blmQgOzNuhIfiROxf4oLU78n5v3+22KyhU9emLqlgCqtQDK/Z+31DhC7toM= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.dev; spf=pass smtp.mailfrom=linux.dev; dkim=pass (1024-bit key) header.d=linux.dev header.i=@linux.dev header.b=VRQ7d5UD; arc=none smtp.client-ip=95.215.58.183 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.dev Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=linux.dev Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linux.dev header.i=@linux.dev header.b="VRQ7d5UD" X-Report-Abuse: Please report any abuse attempt to abuse@migadu.com and include these headers. DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux.dev; s=key1; t=1740416399; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=sXImHF+AatB2zWehHEZzkP3DgCbk67G0CTnxuxdEVxE=; b=VRQ7d5UDZQ1lPbaD4QY3raHMG/CkJGI/nZfTYxApXF6OrKHQmK48OXXrKmvPgzvdYXI1p4 Y8+Q7CoALwE6/jjdTZzmW+QWELQVwm0QjdIJlgFTjRqaXIxo9c5EmE2ubWNA1pl/HGOmpR KcwJSvVpL3KJkZJ+HVK9i5AvoqMmKDg= From: Tao Chen To: ast@kernel.org, daniel@iogearbox.net, andrii@kernel.org, eddyz87@gmail.com, haoluo@google.com, jolsa@kernel.org, qmo@kernel.org Cc: bpf@vger.kernel.org, linux-kernel@vger.kernel.org, chen.dylane@gmail.com, Tao Chen , Tao Chen Subject: [PATCH bpf-next v8 1/5] libbpf: Extract prog load type check from libbpf_probe_bpf_helper Date: Tue, 25 Feb 2025 00:59:08 +0800 Message-Id: <20250224165912.599068-2-chen.dylane@linux.dev> In-Reply-To: <20250224165912.599068-1-chen.dylane@linux.dev> References: <20250224165912.599068-1-chen.dylane@linux.dev> 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 X-Migadu-Flow: FLOW_OUT Content-Type: text/plain; charset="utf-8" Extract prog load type check part from libbpf_probe_bpf_helper suggested by Andrii, which will be used in both libbpf_probe_bpf_{helper, kfunc}. Cc: Tao Chen Reviewed-by: Jiri Olsa Reviewed-by: Eduard Zingerman Signed-off-by: Tao Chen --- tools/lib/bpf/libbpf_probes.c | 31 +++++++++++++++++++------------ 1 file changed, 19 insertions(+), 12 deletions(-) diff --git a/tools/lib/bpf/libbpf_probes.c b/tools/lib/bpf/libbpf_probes.c index 9dfbe7750f56..a48a557314f6 100644 --- a/tools/lib/bpf/libbpf_probes.c +++ b/tools/lib/bpf/libbpf_probes.c @@ -413,6 +413,23 @@ int libbpf_probe_bpf_map_type(enum bpf_map_type map_ty= pe, const void *opts) return libbpf_err(ret); } =20 +static bool can_probe_prog_type(enum bpf_prog_type prog_type) +{ + /* we can't successfully load all prog types to check for BPF helper + * and kfunc support. + */ + switch (prog_type) { + case BPF_PROG_TYPE_TRACING: + case BPF_PROG_TYPE_EXT: + case BPF_PROG_TYPE_LSM: + case BPF_PROG_TYPE_STRUCT_OPS: + return false; + default: + break; + } + return true; +} + int libbpf_probe_bpf_helper(enum bpf_prog_type prog_type, enum bpf_func_id= helper_id, const void *opts) { @@ -427,18 +444,8 @@ int libbpf_probe_bpf_helper(enum bpf_prog_type prog_ty= pe, enum bpf_func_id helpe if (opts) return libbpf_err(-EINVAL); =20 - /* we can't successfully load all prog types to check for BPF helper - * support, so bail out with -EOPNOTSUPP error - */ - switch (prog_type) { - case BPF_PROG_TYPE_TRACING: - case BPF_PROG_TYPE_EXT: - case BPF_PROG_TYPE_LSM: - case BPF_PROG_TYPE_STRUCT_OPS: - return -EOPNOTSUPP; - default: - break; - } + if (!can_probe_prog_type(prog_type)) + return libbpf_err(-EOPNOTSUPP); =20 buf[0] =3D '\0'; ret =3D probe_prog_load(prog_type, insns, insn_cnt, buf, sizeof(buf)); --=20 2.43.0 From nobody Mon Dec 15 21:42:45 2025 Received: from out-182.mta1.migadu.com (out-182.mta1.migadu.com [95.215.58.182]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id DEDCD264A93 for ; Mon, 24 Feb 2025 17:02:43 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=95.215.58.182 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1740416565; cv=none; b=rqnTddzt/qXZXRnqKTAOc0wF+5boPrFWE9mVBQu3VmPj2exFnipnX0rYXxCQqXioHSHgY7sHGsFS6eCrF490QTu0s8Lbrnwhc+2GNbzqqdbl85+GVgYH6PB0wMX4W33WLT4et6jnfAo4LByebgZAS3kt6GVKeYSsECmvtxYqPPE= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1740416565; c=relaxed/simple; bh=aG8o/kahVF1tm5V+3pDDlV1oJXm/dksJNGytP15/dhA=; h=From:To:Cc:Subject:Date:Message-Id:In-Reply-To:References: MIME-Version; b=nx3dtgHxk0jEdf7GGlUUcvCQljJ1SXWyrtP4YvIyQabhobv9jsPYzgPkJIcInnGRugu3PMvEJrIgK1aoTBNIvrjvG6xF5BG4Jhrqa0fTMhQNxyg213zgVpxE3oH12u7xaRh+u+9SaRaAh1IjxVp1QvOyHUynn4i75Prfxs754q4= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.dev; spf=pass smtp.mailfrom=linux.dev; dkim=pass (1024-bit key) header.d=linux.dev header.i=@linux.dev header.b=lKSG3ALO; arc=none smtp.client-ip=95.215.58.182 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.dev Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=linux.dev Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linux.dev header.i=@linux.dev header.b="lKSG3ALO" X-Report-Abuse: Please report any abuse attempt to abuse@migadu.com and include these headers. DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux.dev; s=key1; t=1740416552; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=7PGzrKBqkUWVbwyFTBIov9XC7SmgDrzD5PuL2n2Yx4M=; b=lKSG3ALOVcqBH1KgzjTr1euc/9OJwGCjz5RM3AN/1TuYVq8tQBSbRo91P3booy2s4BDbiU HtOhUDXeT3cwhignhs5lYMWWfo5Q480JdYieUP+7uIT13jyqEVFRJ6eoTBjA8PuAixSfnZ Ikp/S5ya+lttt1/bBwv6sOpVkVxg1mc= From: Tao Chen To: ast@kernel.org, daniel@iogearbox.net, andrii@kernel.org, eddyz87@gmail.com, haoluo@google.com, jolsa@kernel.org, qmo@kernel.org Cc: bpf@vger.kernel.org, linux-kernel@vger.kernel.org, chen.dylane@gmail.com, Tao Chen , Tao Chen Subject: [PATCH bpf-next v8 2/5] libbpf: Init fd_array when prog probe load Date: Tue, 25 Feb 2025 00:59:09 +0800 Message-Id: <20250224165912.599068-3-chen.dylane@linux.dev> In-Reply-To: <20250224165912.599068-1-chen.dylane@linux.dev> References: <20250224165912.599068-1-chen.dylane@linux.dev> 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 X-Migadu-Flow: FLOW_OUT Content-Type: text/plain; charset="utf-8" fd_array used to store module btf fd, which will be used for kfunc probe in module btf. Cc: Tao Chen Reviewed-by: Jiri Olsa Reviewed-by: Eduard Zingerman Signed-off-by: Tao Chen --- tools/lib/bpf/libbpf_probes.c | 7 ++++--- 1 file changed, 4 insertions(+), 3 deletions(-) diff --git a/tools/lib/bpf/libbpf_probes.c b/tools/lib/bpf/libbpf_probes.c index a48a557314f6..de2b1205b436 100644 --- a/tools/lib/bpf/libbpf_probes.c +++ b/tools/lib/bpf/libbpf_probes.c @@ -102,12 +102,13 @@ __u32 get_kernel_version(void) =20 static int probe_prog_load(enum bpf_prog_type prog_type, const struct bpf_insn *insns, size_t insns_cnt, - char *log_buf, size_t log_buf_sz) + int *fd_array, char *log_buf, size_t log_buf_sz) { LIBBPF_OPTS(bpf_prog_load_opts, opts, .log_buf =3D log_buf, .log_size =3D log_buf_sz, .log_level =3D log_buf ? 1 : 0, + .fd_array =3D fd_array, ); int fd, err, exp_err =3D 0; const char *exp_msg =3D NULL; @@ -214,7 +215,7 @@ int libbpf_probe_bpf_prog_type(enum bpf_prog_type prog_= type, const void *opts) if (opts) return libbpf_err(-EINVAL); =20 - ret =3D probe_prog_load(prog_type, insns, insn_cnt, NULL, 0); + ret =3D probe_prog_load(prog_type, insns, insn_cnt, NULL, NULL, 0); return libbpf_err(ret); } =20 @@ -448,7 +449,7 @@ int libbpf_probe_bpf_helper(enum bpf_prog_type prog_typ= e, enum bpf_func_id helpe return libbpf_err(-EOPNOTSUPP); =20 buf[0] =3D '\0'; - ret =3D probe_prog_load(prog_type, insns, insn_cnt, buf, sizeof(buf)); + ret =3D probe_prog_load(prog_type, insns, insn_cnt, NULL, buf, sizeof(buf= )); if (ret < 0) return libbpf_err(ret); =20 --=20 2.43.0 From nobody Mon Dec 15 21:42:45 2025 Received: from out-186.mta0.migadu.com (out-186.mta0.migadu.com [91.218.175.186]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 735142673B2 for ; Mon, 24 Feb 2025 17:02:40 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=91.218.175.186 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1740416562; cv=none; b=bSxJyNFN+QgVixSI2rJ2x+8uW8HO59mUOKDWTUIbUQaHi4rrhBbFnJhaVeK8oIlPynbW+VIq5c8nIAytss2oKA+lGFp8+H9Scq1slthTCIJF6mwKdf3Jy8UBBtIaTioRXt7D4TkkdUx6rVzkeXp1qhz3UBkowzqWRK3s3BKTteQ= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1740416562; c=relaxed/simple; bh=pWXtRo6gHo4DEJYISY33x6GfcFgrTWBD7e3ZWdUBELE=; h=From:To:Cc:Subject:Date:Message-Id:In-Reply-To:References: MIME-Version; b=uZ2REVroV7YF3G+/JOvG4JzOtV3PkIxO4OYTQR7bm7q3S42ZhdxyetU1tRDj2RqAsw/Rc8XoFHFRxecmzLhBKGyMM4bYGLSHP4Nlbu/AT2JX3rCVEBskstw6CFfDhB6OgVczc2K7V9hCLDZxnnehERWh4uaszcCwRgDtkUv8AmI= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.dev; spf=pass smtp.mailfrom=linux.dev; dkim=pass (1024-bit key) header.d=linux.dev header.i=@linux.dev header.b=Lz0y26a5; arc=none smtp.client-ip=91.218.175.186 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.dev Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=linux.dev Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linux.dev header.i=@linux.dev header.b="Lz0y26a5" X-Report-Abuse: Please report any abuse attempt to abuse@migadu.com and include these headers. DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux.dev; s=key1; t=1740416558; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=vB83pcYOlAu6TvcgZccjSdqVZZ3UtGjDlwpT4jeGmb0=; b=Lz0y26a5V7KXg7FX07XUJ2txVeZf0Oz3QlBlyTSo404fe1maCZJbVz66PGD3I6E2K9ObMD T+PHStGd/jMyzcSRV7u5WYp5qsip6Hx+i2LHL+RabM+jWtrVBTi5D2b8DseZySobBBnAZ9 VR7W8OTO/0uXWb0PURAxHFWaOJUNWOY= From: Tao Chen To: ast@kernel.org, daniel@iogearbox.net, andrii@kernel.org, eddyz87@gmail.com, haoluo@google.com, jolsa@kernel.org, qmo@kernel.org Cc: bpf@vger.kernel.org, linux-kernel@vger.kernel.org, chen.dylane@gmail.com, Tao Chen , Tao Chen Subject: [PATCH bpf-next v8 3/5] libbpf: Add libbpf_probe_bpf_kfunc API Date: Tue, 25 Feb 2025 00:59:10 +0800 Message-Id: <20250224165912.599068-4-chen.dylane@linux.dev> In-Reply-To: <20250224165912.599068-1-chen.dylane@linux.dev> References: <20250224165912.599068-1-chen.dylane@linux.dev> 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 X-Migadu-Flow: FLOW_OUT Content-Type: text/plain; charset="utf-8" Similarly to libbpf_probe_bpf_helper, the libbpf_probe_bpf_kfunc used to test the availability of the different eBPF kfuncs on the current system. Cc: Tao Chen Reviewed-by: Jiri Olsa Reviewed-by: Eduard Zingerman Signed-off-by: Tao Chen --- tools/lib/bpf/libbpf.h | 19 ++++++++++++- tools/lib/bpf/libbpf.map | 1 + tools/lib/bpf/libbpf_probes.c | 51 +++++++++++++++++++++++++++++++++++ 3 files changed, 70 insertions(+), 1 deletion(-) diff --git a/tools/lib/bpf/libbpf.h b/tools/lib/bpf/libbpf.h index 3020ee45303a..c79b4475b956 100644 --- a/tools/lib/bpf/libbpf.h +++ b/tools/lib/bpf/libbpf.h @@ -1680,7 +1680,24 @@ LIBBPF_API int libbpf_probe_bpf_map_type(enum bpf_ma= p_type map_type, const void */ LIBBPF_API int libbpf_probe_bpf_helper(enum bpf_prog_type prog_type, enum bpf_func_id helper_id, const void *opts); - +/** + * @brief **libbpf_probe_bpf_kfunc()** detects if host kernel supports the + * use of a given BPF kfunc from specified BPF program type. + * @param prog_type BPF program type used to check the support of BPF kfunc + * @param kfunc_id The btf ID of BPF kfunc to check support for + * @param btf_fd The module BTF FD, if kfunc is defined in kernel module, + * btf_fd is used to point to module's BTF, which is >=3D 0, and < 0 means= kfunc + * defined in vmlinux. + * @param opts reserved for future extensibility, should be NULL + * @return 1, if given combination of program type and kfunc is supported;= 0, + * if the combination is not supported; negative error code if feature + * detection for provided input arguments failed or can't be performed + * + * Make sure the process has required set of CAP_* permissions (or runs as + * root) when performing feature checking. + */ +LIBBPF_API int libbpf_probe_bpf_kfunc(enum bpf_prog_type prog_type, + int kfunc_id, int btf_fd, const void *opts); /** * @brief **libbpf_num_possible_cpus()** is a helper function to get the * number of possible CPUs that the host kernel supports and expects. diff --git a/tools/lib/bpf/libbpf.map b/tools/lib/bpf/libbpf.map index b5a838de6f47..3bbfe13aeb6a 100644 --- a/tools/lib/bpf/libbpf.map +++ b/tools/lib/bpf/libbpf.map @@ -438,4 +438,5 @@ LIBBPF_1.6.0 { bpf_linker__new_fd; btf__add_decl_attr; btf__add_type_attr; + libbpf_probe_bpf_kfunc; } LIBBPF_1.5.0; diff --git a/tools/lib/bpf/libbpf_probes.c b/tools/lib/bpf/libbpf_probes.c index de2b1205b436..8efebc18a215 100644 --- a/tools/lib/bpf/libbpf_probes.c +++ b/tools/lib/bpf/libbpf_probes.c @@ -431,6 +431,57 @@ static bool can_probe_prog_type(enum bpf_prog_type pro= g_type) return true; } =20 +int libbpf_probe_bpf_kfunc(enum bpf_prog_type prog_type, int kfunc_id, int= btf_fd, + const void *opts) +{ + struct bpf_insn insns[] =3D { + BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, BPF_PSEUDO_KFUNC_CALL, 1, kfunc_id), + BPF_EXIT_INSN(), + }; + const size_t insn_cnt =3D ARRAY_SIZE(insns); + char buf[4096]; + int fd_array[2] =3D {-1}; + int ret; + + if (opts) + return libbpf_err(-EINVAL); + + if (!can_probe_prog_type(prog_type)) + return libbpf_err(-EOPNOTSUPP); + + if (btf_fd >=3D 0) + fd_array[1] =3D btf_fd; + else + /* insn.off =3D 0, means vmlinux btf */ + insns[0].off =3D 0; + + buf[0] =3D '\0'; + ret =3D probe_prog_load(prog_type, insns, insn_cnt, btf_fd >=3D 0 ? fd_ar= ray : NULL, + buf, sizeof(buf)); + if (ret < 0) + return libbpf_err(ret); + + if (ret > 0) + return 1; /* assume supported */ + + /* If BPF verifier recognizes BPF kfunc but it's not supported for + * given BPF program type, it will emit "calling kernel function + * is not allowed". If the kfunc id is invalid, + * it will emit "kernel btf_id is not a function". If BTF fd + * invalid in module BTF, it will emit "invalid module BTF fd specified" = or + * "negative offset disallowed for kernel module function call". If + * kfunc prog not dev buound, it will emit "metadata kfuncs require + * device-bound program". + */ + if (strstr(buf, "not allowed") || strstr(buf, "not a function") || + strstr(buf, "invalid module BTF fd") || + strstr(buf, "negative offset disallowed") || + strstr(buf, "device-bound program")) + return 0; + + return 1; +} + int libbpf_probe_bpf_helper(enum bpf_prog_type prog_type, enum bpf_func_id= helper_id, const void *opts) { --=20 2.43.0 From nobody Mon Dec 15 21:42:45 2025 Received: from out-172.mta0.migadu.com (out-172.mta0.migadu.com [91.218.175.172]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 56911264F85 for ; Mon, 24 Feb 2025 17:02:48 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=91.218.175.172 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1740416570; cv=none; b=FdsjMjWEcACNDzituT4p+nu1JlsKDL+wclm3lzUk9p+iFLoaD+4ZavbIytnHi0qCU+RU0I0nqvfxjpEHwLOgUK2/F5oLntd85dBbovLFWkx17dQvrtiwLN4Y2ojpntcZUwEpmozNt8D28TGbMZIL6ZXnF9Tby7dPcvKqsBLhVwU= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1740416570; c=relaxed/simple; bh=2/tNsQbKiTkaxCoHs1UKZQvUCGIwo1zazwTLngtVyq0=; h=From:To:Cc:Subject:Date:Message-Id:In-Reply-To:References: MIME-Version; b=QfvXPMqMeBsxlOCfps6+evwYg4l8nN0aE57nJS5AMTm4xZSLStXmCopDHxGU5AwZZo1OQOQNcgAqGtEx8Ao6y/CVhIJYW4pIce7y4r5tAm03mU3hwQFmpRJGjmwxcNeDjRIHJiGtoCLbJwQC1pK/gztvAeHCi2Pj6S2j1EFPYC0= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.dev; spf=pass smtp.mailfrom=linux.dev; dkim=pass (1024-bit key) header.d=linux.dev header.i=@linux.dev header.b=V5ChfgId; arc=none smtp.client-ip=91.218.175.172 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.dev Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=linux.dev Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linux.dev header.i=@linux.dev header.b="V5ChfgId" X-Report-Abuse: Please report any abuse attempt to abuse@migadu.com and include these headers. DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux.dev; s=key1; t=1740416565; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=z6dFsrJK1KUGJWoZLEUFQHIqOltFLVPZ4LRzfSz7zsM=; b=V5ChfgIdY+YuXDWOmrz5dDv7LDtZpqj3plpZq5HR6FE8Mp/6gXq9WETqpPal5m9wiPBSe5 PfCihKDs9jgUVJt/b72G+O6c35N2j+VDY2NIdDEWFWDCNVNYj/8H+lVxP7Hy2QIJBMcEKa chKZ/qBrAnhr2K68D+2eTJ4W2g3p7xk= From: Tao Chen To: ast@kernel.org, daniel@iogearbox.net, andrii@kernel.org, eddyz87@gmail.com, haoluo@google.com, jolsa@kernel.org, qmo@kernel.org Cc: bpf@vger.kernel.org, linux-kernel@vger.kernel.org, chen.dylane@gmail.com, Tao Chen Subject: [PATCH bpf-next v8 4/5] libbpf: Init kprobe prog expected_attach_type for kfunc probe Date: Tue, 25 Feb 2025 00:59:11 +0800 Message-Id: <20250224165912.599068-5-chen.dylane@linux.dev> In-Reply-To: <20250224165912.599068-1-chen.dylane@linux.dev> References: <20250224165912.599068-1-chen.dylane@linux.dev> 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 X-Migadu-Flow: FLOW_OUT Content-Type: text/plain; charset="utf-8" Kprobe prog type kfuncs like bpf_session_is_return and bpf_session_cookie will check the expected_attach_type, so init the expected_attach_type here. Signed-off-by: Tao Chen --- tools/lib/bpf/libbpf_probes.c | 1 + 1 file changed, 1 insertion(+) diff --git a/tools/lib/bpf/libbpf_probes.c b/tools/lib/bpf/libbpf_probes.c index 8efebc18a215..bb5b457ddc80 100644 --- a/tools/lib/bpf/libbpf_probes.c +++ b/tools/lib/bpf/libbpf_probes.c @@ -126,6 +126,7 @@ static int probe_prog_load(enum bpf_prog_type prog_type, break; case BPF_PROG_TYPE_KPROBE: opts.kern_version =3D get_kernel_version(); + opts.expected_attach_type =3D BPF_TRACE_KPROBE_SESSION; break; case BPF_PROG_TYPE_LIRC_MODE2: opts.expected_attach_type =3D BPF_LIRC_MODE2; --=20 2.43.0 From nobody Mon Dec 15 21:42:45 2025 Received: from out-176.mta1.migadu.com (out-176.mta1.migadu.com [95.215.58.176]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id AD14B264A9E for ; Mon, 24 Feb 2025 17:02:55 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=95.215.58.176 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1740416577; cv=none; b=lBXsO7SHVw3Gr9Sl9Rw3NW6ROdiV9ZGPSzZS0131+GAYMo+/6ynHpJIX1FxJGdlt0eVY6rTr26l5ZrP/RN3YxIZ6hd8Wu2xKAOyFluEdLJE9qb42oU81pZTS5NGWfBEAVkn3RJrCFoSOKgC2AgxpIgUqmsuNsAMxDuznm0jYWzo= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1740416577; c=relaxed/simple; bh=e1HU03QaEH/WJqwMrSHwDYP8oWlp/FRk7I/D+9cATTo=; h=From:To:Cc:Subject:Date:Message-Id:In-Reply-To:References: MIME-Version; b=anxNUEGVZL/kse+IrteziPjAHBRpyWytHcAi2Ealcb8MPCuZz1jfvLfcsl5uhgExYlslW0xsoi1uyhuiqF4q2ADY4ILiBZuFLp/YaRU+I7jQnTzoO99szVOLZx6NO5jH4ESQ9lw7as2fZrwwo3nlH/njZaU3tMcrOunss5CZhSk= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.dev; spf=pass smtp.mailfrom=linux.dev; dkim=pass (1024-bit key) header.d=linux.dev header.i=@linux.dev header.b=lpDm5H4s; arc=none smtp.client-ip=95.215.58.176 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.dev Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=linux.dev Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linux.dev header.i=@linux.dev header.b="lpDm5H4s" X-Report-Abuse: Please report any abuse attempt to abuse@migadu.com and include these headers. DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux.dev; s=key1; t=1740416573; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=qiQKTOacPogCTZt2sF84QiGnZvXEsGlrdkRpybzF4+0=; b=lpDm5H4sJdnzN0FVGveCI+7jrxzFfbnhmXhpxW3Nnuhh6TdXNlMAdIcXDFOXlU/7+yYqRC kg744NhFn8Epzua9iaUK3upeY8Ab4LxungmSXp5/ewmkDWRmAHr4VDpyOQurVCcO/LyXAP P5CH5gjfz8nr0fvspiPu0PQ08IjrGzs= From: Tao Chen To: ast@kernel.org, daniel@iogearbox.net, andrii@kernel.org, eddyz87@gmail.com, haoluo@google.com, jolsa@kernel.org, qmo@kernel.org Cc: bpf@vger.kernel.org, linux-kernel@vger.kernel.org, chen.dylane@gmail.com, Tao Chen , Tao Chen Subject: [PATCH bpf-next v8 5/5] selftests/bpf: Add libbpf_probe_bpf_kfunc API selftests Date: Tue, 25 Feb 2025 00:59:12 +0800 Message-Id: <20250224165912.599068-6-chen.dylane@linux.dev> In-Reply-To: <20250224165912.599068-1-chen.dylane@linux.dev> References: <20250224165912.599068-1-chen.dylane@linux.dev> 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 X-Migadu-Flow: FLOW_OUT Content-Type: text/plain; charset="utf-8" Add selftests for prog_kfunc feature probing. ./test_progs -t libbpf_probe_kfuncs #153 libbpf_probe_kfuncs:OK Summary: 1/0 PASSED, 0 SKIPPED, 0 FAILED Cc: Tao Chen Reviewed-by: Jiri Olsa Reviewed-by: Eduard Zingerman Signed-off-by: Tao Chen --- .../selftests/bpf/prog_tests/libbpf_probes.c | 111 ++++++++++++++++++ 1 file changed, 111 insertions(+) diff --git a/tools/testing/selftests/bpf/prog_tests/libbpf_probes.c b/tools= /testing/selftests/bpf/prog_tests/libbpf_probes.c index 4ed46ed58a7b..d8f5475a94ce 100644 --- a/tools/testing/selftests/bpf/prog_tests/libbpf_probes.c +++ b/tools/testing/selftests/bpf/prog_tests/libbpf_probes.c @@ -126,3 +126,114 @@ void test_libbpf_probe_helpers(void) ASSERT_EQ(res, d->supported, buf); } } + +static int module_btf_fd(char *module) +{ + int fd, err; + __u32 id =3D 0, len; + struct bpf_btf_info info; + char name[64]; + + while (true) { + err =3D bpf_btf_get_next_id(id, &id); + if (err) + return -1; + + fd =3D bpf_btf_get_fd_by_id(id); + if (fd < 0) { + if (errno =3D=3D ENOENT) + continue; + return -1; + } + len =3D sizeof(info); + memset(&info, 0, sizeof(info)); + info.name =3D ptr_to_u64(name); + info.name_len =3D sizeof(name); + err =3D bpf_btf_get_info_by_fd(fd, &info, &len); + if (err) { + close(fd); + return -1; + } + /* find target module BTF */ + if (!strcmp(name, module)) + break; + + close(fd); + } + + return fd; +} + +void test_libbpf_probe_kfuncs(void) +{ + int ret, kfunc_id, fd; + char *kfunc =3D "bpf_cpumask_create"; + struct btf *vmlinux_btf =3D NULL; + struct btf *module_btf =3D NULL; + + vmlinux_btf =3D btf__parse("/sys/kernel/btf/vmlinux", NULL); + if (!ASSERT_OK_PTR(vmlinux_btf, "btf_parse")) + return; + + kfunc_id =3D btf__find_by_name_kind(vmlinux_btf, kfunc, BTF_KIND_FUNC); + if (!ASSERT_GT(kfunc_id, 0, kfunc)) + goto cleanup; + + /* prog BPF_PROG_TYPE_SYSCALL supports kfunc bpf_cpumask_create */ + ret =3D libbpf_probe_bpf_kfunc(BPF_PROG_TYPE_SYSCALL, kfunc_id, -1, NULL); + if (!ASSERT_EQ(ret, 1, "kfunc in vmlinux support")) + goto cleanup; + + /* prog BPF_PROG_TYPE_KPROBE does not support kfunc bpf_cpumask_create */ + ret =3D libbpf_probe_bpf_kfunc(BPF_PROG_TYPE_KPROBE, kfunc_id, -1, NULL); + if (!ASSERT_EQ(ret, 0, "kfunc in vmlinux not suuport")) + goto cleanup; + + ret =3D libbpf_probe_bpf_kfunc(BPF_PROG_TYPE_KPROBE, -1, -1, NULL); + if (!ASSERT_EQ(ret, 0, "invalid kfunc id:-1")) + goto cleanup; + + ret =3D libbpf_probe_bpf_kfunc(100000, kfunc_id, -1, NULL); + if (!ASSERT_ERR(ret, "invalid prog type:100000")) + goto cleanup; + + if (!env.has_testmod) + goto cleanup; + + module_btf =3D btf__load_module_btf("bpf_testmod", vmlinux_btf); + if (!ASSERT_OK_PTR(module_btf, "load module BTF")) + goto cleanup; + + kfunc_id =3D btf__find_by_name(module_btf, "bpf_kfunc_call_test1"); + if (!ASSERT_GT(kfunc_id, 0, "func not found")) + goto cleanup; + + fd =3D module_btf_fd("bpf_testmod"); + if (!ASSERT_GE(fd, 0, "module BTF fd")) + goto cleanup; + + /* prog BPF_PROG_TYPE_SYSCALL supports kfunc bpf_kfunc_call_test1 in bpf_= testmod */ + ret =3D libbpf_probe_bpf_kfunc(BPF_PROG_TYPE_SYSCALL, kfunc_id, fd, NULL); + if (!ASSERT_EQ(ret, 1, "kfunc in module BTF support")) + goto cleanup_fd; + + /* prog BPF_PROG_TYPE_KPROBE does not support kfunc bpf_kfunc_call_test1 + * in bpf_testmod + */ + ret =3D libbpf_probe_bpf_kfunc(BPF_PROG_TYPE_KPROBE, kfunc_id, fd, NULL); + if (!ASSERT_EQ(ret, 0, "kfunc in module BTF not support")) + goto cleanup_fd; + + ret =3D libbpf_probe_bpf_kfunc(BPF_PROG_TYPE_SYSCALL, -1, fd, NULL); + if (!ASSERT_EQ(ret, 0, "invalid kfunc id in module BTF")) + goto cleanup_fd; + + ret =3D libbpf_probe_bpf_kfunc(BPF_PROG_TYPE_SYSCALL, kfunc_id, 100, NULL= ); + ASSERT_EQ(ret, 0, "invalid BTF fd in module BTF"); + +cleanup_fd: + close(fd); +cleanup: + btf__free(vmlinux_btf); + btf__free(module_btf); +} --=20 2.43.0