From nobody Sat Feb 7 20:58:03 2026 Received: from out-189.mta0.migadu.com (out-189.mta0.migadu.com [91.218.175.189]) (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 D3ED23502A9 for ; Tue, 6 Jan 2026 17:22:05 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=91.218.175.189 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1767720127; cv=none; b=HUjijeYwQk/hPV7SpdH0jI1A988AtaRKHcbcRjKRQJfqRtztjD7Y8DfLHRs+3A4ebcZgjjKbT0qEQVVgrb3GV8C9V+2gwgcjxYT9CmIfv542dQmPlKR1h0xrbK8axDiHbPvzMASGuEmZddSP0pNibb3bKVAExGSEioP7KP24grs= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1767720127; c=relaxed/simple; bh=HxI4+nzQuzg70aSRlSj9KKaRq21uALuyDmmimZAfIfI=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=E+2VRaODYNanfnqK/++QhzKgx+KOW3YLLiEmegGYcPIywVMDX387JGXpGBVEapUPVSoLSJhY899Hc8zJOmSafuK7RHuaXpFy+/pEOInsb3Of5kV2Km7ws75gLUpAVKCteRrGsB51up4Tw/rLpCqvU61yS+3PYBQ4M3fawrQHmUM= 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=A3x0HJVr; arc=none smtp.client-ip=91.218.175.189 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="A3x0HJVr" 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=1767720123; 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=mSPAXTe59AXqGHWDQ1uMbUsQxBwsOMvl1BeG421F/78=; b=A3x0HJVrxScEAlTcSIG2ScmXBWFPoL8hCdG9KeFsqmeMKN4ms+ZAsaB9T5hSD/DJfMS2/P +ElCGOriVYdSUPvMfdh2oPLuohKcw8t7dN47czjtJA3obQovjwklGy8PsyCg6f/HjpydsI LLAT0bxLCCpF8rhkx2rLuSLMmkFUaWg= From: Leon Hwang To: bpf@vger.kernel.org Cc: Alexei Starovoitov , Daniel Borkmann , Andrii Nakryiko , Martin KaFai Lau , Eduard Zingerman , Song Liu , Yonghong Song , John Fastabend , KP Singh , Stanislav Fomichev , Hao Luo , Jiri Olsa , Shuah Khan , Christian Brauner , Oleg Nesterov , Leon Hwang , Seth Forshee , Yuichiro Tsuji , Andrey Albershteyn , Willem de Bruijn , Jason Xing , Paul Chaignon , 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: [RESEND PATCH bpf-next v4 8/9] libbpf: Add common attr support for map_create Date: Wed, 7 Jan 2026 01:20:17 +0800 Message-ID: <20260106172018.57757-9-leon.hwang@linux.dev> In-Reply-To: <20260106172018.57757-1-leon.hwang@linux.dev> References: <20260106172018.57757-1-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, it is now possible to retrieve detailed error messages when map creation fails by using the 'log_buf' field from the common attributes. Introduce a new struct bpf_syscall_common_attr_opts, which wraps these new fields, 'log_buf', 'log_size', 'log_level', and 'log_true_size'. Extend 'bpf_map_create_opts' with a new field, 'cattr_opts', allowing users to capture and inspect those log messages. Signed-off-by: Leon Hwang --- tools/lib/bpf/bpf.c | 15 ++++++++++++++- tools/lib/bpf/bpf.h | 17 ++++++++++++++++- 2 files changed, 30 insertions(+), 2 deletions(-) diff --git a/tools/lib/bpf/bpf.c b/tools/lib/bpf/bpf.c index 689ade4a822b..4a1ba4951785 100644 --- a/tools/lib/bpf/bpf.c +++ b/tools/lib/bpf/bpf.c @@ -207,6 +207,9 @@ 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 common_attrs_sz =3D sizeof(struct bpf_common_attr); + struct bpf_syscall_common_attr_opts *cattr_opts; + struct bpf_common_attr common_attrs; union bpf_attr attr; int fd; =20 @@ -240,7 +243,17 @@ 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); + cattr_opts =3D OPTS_GET(opts, cattr_opts, NULL); + if (cattr_opts && feat_supported(NULL, FEAT_EXTENDED_SYSCALL)) { + memset(&common_attrs, 0, common_attrs_sz); + common_attrs.log_buf =3D ptr_to_u64(OPTS_GET(cattr_opts, log_buf, NULL)); + common_attrs.log_size =3D OPTS_GET(cattr_opts, log_size, 0); + common_attrs.log_level =3D OPTS_GET(cattr_opts, log_level, 0); + fd =3D sys_bpf_ext_fd(BPF_MAP_CREATE, &attr, attr_sz, &common_attrs, com= mon_attrs_sz); + OPTS_SET(cattr_opts, log_true_size, common_attrs.log_true_size); + } else { + fd =3D sys_bpf_fd(BPF_MAP_CREATE, &attr, attr_sz); + } return libbpf_err_errno(fd); } =20 diff --git a/tools/lib/bpf/bpf.h b/tools/lib/bpf/bpf.h index 1f9c28d27795..6f544c205b89 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_syscall_common_attr_opts { + size_t sz; /* size of this struct for forward/backward compatibility */ + + const char *log_buf; + __u32 log_size; + __u32 log_level; + __u32 log_true_size; + + size_t :0; +}; +#define bpf_syscall_common_attr_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_syscall_common_attr_opts *cattr_opts; + size_t :0; }; -#define bpf_map_create_opts__last_field excl_prog_hash_size +#define bpf_map_create_opts__last_field cattr_opts =20 LIBBPF_API int bpf_map_create(enum bpf_map_type map_type, const char *map_name, --=20 2.52.0