From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-ej1-f73.google.com (mail-ej1-f73.google.com [209.85.218.73]) (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 733473DA7EC for ; Tue, 26 May 2026 12:13:03 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.218.73 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1779797585; cv=none; b=FHP+8CGGaqUrtVXIDUZCJ6MEPcWLhLZ5IRWCm41zD/TSMzQhIoOc9RJT+G503wv9vJfRpDzCSQ0VG+/mr4B0Hh119mRIwTzJWZMlaxppvD1GUBSXYtsgBaNYinLXbPYR7eRKdEIcWHLwsXxE1aOHg5R/tZ3bVPFn1KJOACg7FJ0= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1779797585; c=relaxed/simple; bh=r7zcdF8qutzChq8XLk+oXcsBhNew8W4i+fhDiWfimoc=; h=Date:In-Reply-To:Mime-Version:References:Message-ID:Subject:From: To:Cc:Content-Type; b=MvIdKZXklyIg3lFnkOWjHvkdXwweGW7LBTCRWK0v7jOY29ztxV3HTuuCjNEdjpcvgg2XGOPjmlisOES2RJZJeYWE+6m0f6lwmJWWCAl9+obg5DPgqvM1kB6SFjN538IDoov4CF79fee16bvbdFWehIwpBFOuxwXjJp/t7IBwnhs= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=google.com; spf=pass smtp.mailfrom=flex--sidnayyar.bounces.google.com; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b=M7YfKdpm; arc=none smtp.client-ip=209.85.218.73 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=google.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=flex--sidnayyar.bounces.google.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b="M7YfKdpm" Received: by mail-ej1-f73.google.com with SMTP id a640c23a62f3a-bcf70e19516so253818266b.2 for ; Tue, 26 May 2026 05:13:03 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20251104; t=1779797582; x=1780402382; darn=vger.kernel.org; h=cc:to:from:subject:message-id:references:mime-version:in-reply-to :date:from:to:cc:subject:date:message-id:reply-to; bh=4Ev6aA3Xe6T1Sew1C3oAjJbhgzPbzt+OHYmVBfkfyNE=; b=M7YfKdpmXwgDhJ6d+bLNkEtm1UZ7Hec3t5tH+k2FlF+Mk+Jvyh25HX7xTDBwi6/mOI w8PW1bq90w5kWcW9ubUqGEjg5sa+rI7puRPcHWrTovId5GDTABgruTcdgVMLfNP2b0e1 asTvZEh0Tkt1NUyvSAXs/r9IYNi9U0A3QLdNeck/6ohJ0Svr1EBleQPijS0EYCfaoNHM mnBSWlggmspb4TZ35ITbAWinNsvJdyw0fiKQzi23oUwhu+czu9/VddRppATAtIoshmbY WAtYbYjJ00cBlX+dhco4JZvcKpj3Egrnnn4kh7d7mHVYMDGlua6DgpJmD0gdC9R3cDDv RNbA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20251104; t=1779797582; x=1780402382; h=cc:to:from:subject:message-id:references:mime-version:in-reply-to :date:x-gm-message-state:from:to:cc:subject:date:message-id:reply-to; bh=4Ev6aA3Xe6T1Sew1C3oAjJbhgzPbzt+OHYmVBfkfyNE=; b=CDu4CN/cbkdsh2Tyq0yEWgcIGeAYkBoKs8OI7mMOwlXGwqypTWhtyJHOaQwmw1ebYs kQxWa/3hqxb6i6zdkjNCCamwHPitMuZEpvQjzjgLqcyW5yvo+TeWeq53CB/d75EDO9vu 8ba+P6cN6BJq0fdtS4eMj2HUUahHwV68UHVImXYmiRHv2deYue/+rP5+7wrX9HYVfIGd Z5+RW318CcL4nkkdGf9k+7CiPlrKg9XTDo5Z0PCGR5GDUXrhui2q9Zq5M50LC5czmIIO RQWqm/rKP+rp6Dy76XkYsadDdAs3RoxlujTBA2dxtliGBuPRTbJNbljaqy53UNEJj2cl 9zug== X-Forwarded-Encrypted: i=1; AFNElJ/TyfD0JkcS3CkLVcT4uK+oxybRibbf8w+ErijzLNijxmz2GtpwAlGc97KXRdGccAJcrhx42DJk01NdM0E=@vger.kernel.org X-Gm-Message-State: AOJu0Yxbe0vxd4hsq84DGOoEUDAWQJvASy9GP4nErjZHjTplwGLWGlLR OCEECi5LPWmcZW/osugNYTFD2nxUuQkKnXQ8PPD4DfR2I+QEKfje/YqUZLxwK67UYMc76JII3VE KQNhpHK8SG5fCZKU1PQ== X-Received: from ejdbv4.prod.google.com ([2002:a17:907:fd04:b0:bcb:7e65:e5b3]) (user=sidnayyar job=prod-delivery.src-stubby-dispatcher) by 2002:a17:907:3e99:b0:be2:cd33:213f with SMTP id a640c23a62f3a-be2cd332452mr185324366b.17.1779797581687; Tue, 26 May 2026 05:13:01 -0700 (PDT) Date: Tue, 26 May 2026 12:12:56 +0000 In-Reply-To: <20260526-libbpf-load-vmlinux-btf-in-gen_loader-mode-v2-0-6750f5859bc6@google.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: Mime-Version: 1.0 References: <20260526-libbpf-load-vmlinux-btf-in-gen_loader-mode-v2-0-6750f5859bc6@google.com> X-Mailer: b4 0.14.3 Message-ID: <20260526-libbpf-load-vmlinux-btf-in-gen_loader-mode-v2-1-6750f5859bc6@google.com> Subject: [PATCH v2 1/3] libbpf: load vmlinux BTF in gen_loader mode for struct_ops From: Siddharth Nayyar To: Andrii Nakryiko , Eduard Zingerman , Alexei Starovoitov , Daniel Borkmann , Martin KaFai Lau , Kumar Kartikeya Dwivedi , Song Liu , Yonghong Song , Jiri Olsa Cc: bpf@vger.kernel.org, linux-kernel@vger.kernel.org, gprocida@google.com, maennich@google.com, Siddharth Nayyar Content-Type: text/plain; charset="utf-8" During light skeleton generation (`bpftool gen skeleton -L`), libbpf runs in gen_loader mode. Previously, `bpf_object__load_vmlinux_btf()` completely bypassed loading the kernel vmlinux BTF (`obj->btf_vmlinux`) if `gen_loader` was active. However, BPF `struct_ops` maps (such as `sched_ext_ops` maps) require resolving the kernel-side struct type IDs and member sizes at compile/skeleton generation time. Without loading `btf_vmlinux`, libbpf cannot query the kernel BTF types, causing light skeleton generation for `struct_ops` to fail or omit crucial type information. Fix this by modifying the check to load `btf_vmlinux` even in `gen_loader` mode if the BPF object actually requires kernel vmlinux BTF (e.g. contains `struct_ops` maps). Signed-off-by: Siddharth Nayyar --- tools/lib/bpf/libbpf.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) diff --git a/tools/lib/bpf/libbpf.c b/tools/lib/bpf/libbpf.c index 3a80a018fc7d..cb1b7ea884a7 100644 --- a/tools/lib/bpf/libbpf.c +++ b/tools/lib/bpf/libbpf.c @@ -3590,7 +3590,10 @@ static int bpf_object__load_vmlinux_btf(struct bpf_object *obj, bool force) int err; /* btf_vmlinux could be loaded earlier */ - if (obj->btf_vmlinux || obj->gen_loader) + if (obj->btf_vmlinux) + return 0; + + if (obj->gen_loader && !obj_needs_vmlinux_btf(obj)) return 0; if (!force && !obj_needs_vmlinux_btf(obj)) -- 2.54.0.746.g67dd491aae-goog