From nobody Tue Jan 27 00:09:34 2026 Received: from out-187.mta1.migadu.com (out-187.mta1.migadu.com [95.215.58.187]) (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 A19E133C1A5 for ; Mon, 26 Jan 2026 15:16:20 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=95.215.58.187 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1769440582; cv=none; b=DpMGx81LcmFdRvgI9km+T56+ab7K7mH98kv9tU4lVHjwJ7koMVLsAzVPULotN05qGFNdpij1tDKT5rSUDquswJhjSh7f9fpRpYSCc2Wnojk8VZjJ/nHCWqzM/zrmOi9TXKkoCqMkKhuGO/fNS6YRT0sh5juK+yUqqxAEJShJaxI= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1769440582; c=relaxed/simple; bh=RoVqq0qKRTtZkvPyA0OK31cvnMmOvon7veF/oreYESs=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=QSR7D3SPhhg5N4nqnximd9BfqbHn2Ed4IjqdjCoHoMV/4iwy+PNPDhfIKw8XIpyqYOQkGN8PketnzFQTNWmZqYaLI5tywSS0cl+8uskQ1PiPXpVbQB9vkt85U52PRcHUwTFvOyYAnxdz7YaOIUM2eCWHZ+w+AlK8S8Be64u8duI= 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=XY2LFlMy; arc=none smtp.client-ip=95.215.58.187 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="XY2LFlMy" 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=1769440578; 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=AoKtZ5+P7Wxb1aJQ0fxakYbtUswnhN9EllnMlBVZL/I=; b=XY2LFlMyRua21zVYPVq55onF/qOGA8JQjbtcDl33ZQaykqMaOzcBXT0m+MAK9yp+7uvbeJ DA0mN/Nb63QQ2c25Jn4ka4mKGU9jPegmuhN65c64aH0wvqMolVVLzJq78OXHHr7C2TkIuB 5rVkLDoUK1joaJ1Cuq9Um9/ZH9ZP6oc= From: Leon Hwang To: bpf@vger.kernel.org Cc: Alexei Starovoitov , Daniel Borkmann , John Fastabend , Andrii Nakryiko , Martin KaFai Lau , Eduard Zingerman , Song Liu , Yonghong Song , KP Singh , Stanislav Fomichev , Hao Luo , Jiri Olsa , Shuah Khan , Christian Brauner , Seth Forshee , Yuichiro Tsuji , Andrey Albershteyn , Leon Hwang , Willem de Bruijn , Jason Xing , Tao Chen , Mykyta Yatsenko , Kumar Kartikeya Dwivedi , Anton Protopopov , Amery Hung , Rong Tao , linux-kernel@vger.kernel.org, linux-api@vger.kernel.org, linux-kselftest@vger.kernel.org, kernel-patches-bot@fb.com Subject: [PATCH bpf-next v8 8/9] libbpf: Add common attr support for map_create Date: Mon, 26 Jan 2026 23:14:08 +0800 Message-ID: <20260126151409.52072-9-leon.hwang@linux.dev> In-Reply-To: <20260126151409.52072-1-leon.hwang@linux.dev> References: <20260126151409.52072-1-leon.hwang@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" With the previous commit adding common attribute support for BPF_MAP_CREATE, users can now retrieve detailed error messages when map creation fails via the log_buf field. Introduce struct bpf_log_opts with the following fields: log_buf, log_size, log_level, and log_true_size. Extend bpf_map_create_opts with a new field log_opts, allowing users to capture and inspect log messages on map creation failures. Signed-off-by: Leon Hwang --- tools/lib/bpf/bpf.c | 16 +++++++++++++++- tools/lib/bpf/bpf.h | 17 ++++++++++++++++- 2 files changed, 31 insertions(+), 2 deletions(-) diff --git a/tools/lib/bpf/bpf.c b/tools/lib/bpf/bpf.c index 9d8740761b7a..0c3e40844d80 100644 --- a/tools/lib/bpf/bpf.c +++ b/tools/lib/bpf/bpf.c @@ -209,6 +209,9 @@ int bpf_map_create(enum bpf_map_type map_type, const struct bpf_map_create_opts *opts) { const size_t attr_sz =3D offsetofend(union bpf_attr, excl_prog_hash_size); + const size_t attr_common_sz =3D sizeof(struct bpf_common_attr); + struct bpf_common_attr attr_common; + struct bpf_log_opts *log_opts; union bpf_attr attr; int fd; =20 @@ -242,7 +245,18 @@ int bpf_map_create(enum bpf_map_type map_type, attr.excl_prog_hash =3D ptr_to_u64(OPTS_GET(opts, excl_prog_hash, NULL)); attr.excl_prog_hash_size =3D OPTS_GET(opts, excl_prog_hash_size, 0); =20 - fd =3D sys_bpf_fd(BPF_MAP_CREATE, &attr, attr_sz); + log_opts =3D OPTS_GET(opts, log_opts, NULL); + if (log_opts && feat_supported(NULL, FEAT_BPF_SYSCALL_COMMON_ATTRS)) { + memset(&attr_common, 0, attr_common_sz); + attr_common.log_buf =3D ptr_to_u64(OPTS_GET(log_opts, log_buf, NULL)); + attr_common.log_size =3D OPTS_GET(log_opts, log_size, 0); + attr_common.log_level =3D OPTS_GET(log_opts, log_level, 0); + fd =3D sys_bpf_ext_fd(BPF_MAP_CREATE, &attr, attr_sz, &attr_common, attr= _common_sz); + OPTS_SET(log_opts, log_true_size, attr_common.log_true_size); + } else { + fd =3D sys_bpf_fd(BPF_MAP_CREATE, &attr, attr_sz); + OPTS_SET(log_opts, log_true_size, 0); + } return libbpf_err_errno(fd); } =20 diff --git a/tools/lib/bpf/bpf.h b/tools/lib/bpf/bpf.h index 2c8e88ddb674..59673f094f86 100644 --- a/tools/lib/bpf/bpf.h +++ b/tools/lib/bpf/bpf.h @@ -37,6 +37,18 @@ extern "C" { =20 LIBBPF_API int libbpf_set_memlock_rlim(size_t memlock_bytes); =20 +struct bpf_log_opts { + size_t sz; /* size of this struct for forward/backward compatibility */ + + char *log_buf; + __u32 log_size; + __u32 log_level; + __u32 log_true_size; + + size_t :0; +}; +#define bpf_log_opts__last_field log_true_size + struct bpf_map_create_opts { size_t sz; /* size of this struct for forward/backward compatibility */ =20 @@ -57,9 +69,12 @@ struct bpf_map_create_opts { =20 const void *excl_prog_hash; __u32 excl_prog_hash_size; + + struct bpf_log_opts *log_opts; + size_t :0; }; -#define bpf_map_create_opts__last_field excl_prog_hash_size +#define bpf_map_create_opts__last_field log_opts =20 LIBBPF_API int bpf_map_create(enum bpf_map_type map_type, const char *map_name, --=20 2.52.0