From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-dl1-f54.google.com (mail-dl1-f54.google.com [74.125.82.54]) (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 CBD833F23B4 for ; Tue, 20 Jan 2026 18:19:13 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=74.125.82.54 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1768933156; cv=none; b=q+OGGixn/nJxPBI1TteZLBbRS2GRIAZfmCO9PmfWZxK+XkKihr1VToySjzJn+CNUwzHKu0hTC2ZTOzeE2hrSfBTvNf4dyOw5JWOeXwf2bGqlmzXJ0uEB0r3nKNRrmTjbS9/mJFe4Hp5H/sh7pD0NDXdCrcyTrykkR+weDI7Lyhc= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1768933156; c=relaxed/simple; bh=Z6WkaZNjD+eEC5S2sCu+mWSNmR7uwq/DhhVRU9ARdG0=; h=Message-ID:Subject:From:To:Cc:Date:In-Reply-To:References: Content-Type:MIME-Version; b=eJX1XxR3lRvgt2LHTzFrWbaXjT1MUmao3fAcKTKeq9L3owmnDlMp8geJnW8ODlFLIMY0oFd7xyMWNw6f+j1MmoJYi+ycjI+Oa21zLnY6at6FzPcTdV+f6CTbxVdbYFCqjRMSsm9/LLvn6yj130NtwlecyqZhlND5YCmVTFE1ycM= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=gmail.com; spf=pass smtp.mailfrom=gmail.com; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b=eCmndo8X; arc=none smtp.client-ip=74.125.82.54 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=gmail.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=gmail.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="eCmndo8X" Received: by mail-dl1-f54.google.com with SMTP id a92af1059eb24-12448c4d404so4620918c88.1 for ; Tue, 20 Jan 2026 10:19:13 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20230601; t=1768933153; x=1769537953; darn=lists.linux.dev; h=mime-version:user-agent:content-transfer-encoding:references :in-reply-to:date:cc:to:from:subject:message-id:from:to:cc:subject :date:message-id:reply-to; bh=SBww9KLEHQwBhj2b72CiEvbmeQf+WrCHcUWGacrEJTM=; b=eCmndo8XYv0fOKYz4eaDG0v1hMH3pRuYvMJ7MZc2y19kXztpm7hVNiVpyoWTRvmt57 A4nvJTwBLXJgmlrGg039mF/M5zMkluKJtK2HZE8EHu1ZFo5FELSIluXIc+FXhfS9Jzab /g4kV6Vv8isLxwp6Er7XXxHm5vnTh9GKdxzz80SRaV3jvb20ZvMcB6KWnExl4hlISPIm 4f/2KCzX47FnZbdh1zMBTph+66E9oeuqfLNABVuqVT+xzT6Pd/z1DklGpcSQ+cHAQWbY EWNW27+A0ogV2WMDduKKtBq/mylRop90/kxuZQvsW72jjkYxNGsqgAwh/1daRuC5aXCm SNkQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1768933153; x=1769537953; h=mime-version:user-agent:content-transfer-encoding:references :in-reply-to:date:cc:to:from:subject:message-id:x-gm-gg :x-gm-message-state:from:to:cc:subject:date:message-id:reply-to; bh=SBww9KLEHQwBhj2b72CiEvbmeQf+WrCHcUWGacrEJTM=; b=SJeOtqGTJKaySe0xZIPFTyQtGdgPJjU73Eiiwervv4ZW42biLikEa63QMDUvZnwgi8 W+ZZERJdt/L86nXcLO12GziYy6NMYpFW5LStqvLmzfMXlwQO/JpMSl/NTdfchgj8ZF+C QYp/cg79ZZKiVsiN+xTChXY9Zv5rSz/oif6rEtI5IYBjhQ5SPp5cNN5Ectw3tjifdgM8 QJQAqK7pA4txdRgGsyhlK+2mplvk8S8oFH1huM38hrwO8sLWveidlvuGNBr7JUN7hk1J idlCJ02VqIO5u/zrmTV7Wt+CmU69i20rIG9p/p1xlbthV4agGHw+2PveTN24DpfbC0dN hZ3g== X-Forwarded-Encrypted: i=1; AJvYcCU5TSALnJshAeHbRK8r2x+t9//8WvoR2Zr49kWkFT3io5JBt0GtJW3sTZxXtOui0+7H1rPzimxnk2s=@lists.linux.dev X-Gm-Message-State: AOJu0YzmPkO/F6pf3jhVeCnO54xYp7T6WXvh9MUpLp2Who8fsolSSga7 9Y2l8V1PN8r3yyW8+vyuyJEdoPVRyhpUtk5Fp2i4SwQK2BZRF2wnZ8AJ X-Gm-Gg: AY/fxX5lr34wPb0P2D/8jY1c1toFXsPmz32IyrJQW4pAxJ55S32b/xDd+cHYbDvt5xK bqTMOjI9ocMrLmI3Xk2lw9xbqhkuuofAv2/35IXWU9VTMl4l3mMu7r9BGNPTs+wsiKSxjzsEhmX eQi5de6qb0knXACbNdzAU7KTImLWvkCksASrPCD/rfKgl9J+2mneYjJ7oDF/VWCZTvfVEibdTyI KJZEKtCSW/i3X7mNF6vf9P9rgby6d8rCXNUIbbH7qh62XEoJtKe1Y0iF7rymMrupW+pHs2RMt9u 9lA3hLCUTs8VJB4v86Nfxyf/evv8CYIA7Y3qDLyo0COCtgC3gablwSBvBNsqq9SUsF0WaRZCFYS NsD7GopNGSm2eMx7g3wge3DO2UaZ8ztSty324G7my7ASDdCniPrmtOkpvICJCDJX/QkNMx/vI14 0/xXwgxF33f2GjPRMNpWaBZ5j9rW7KewYAObLSxylq/7ul8OF9kiX8lwk06zyzHFzolSaq X-Received: by 2002:a05:7022:e1a:b0:119:e55a:9be7 with SMTP id a92af1059eb24-1246a955faamr2004520c88.3.1768933152685; Tue, 20 Jan 2026 10:19:12 -0800 (PST) Received: from ?IPv6:2a03:83e0:115c:1:b08c:bb3d:92b9:704d? ([2620:10d:c090:500::3:93b1]) by smtp.gmail.com with ESMTPSA id a92af1059eb24-1244aefa7c5sm22503340c88.10.2026.01.20.10.19.10 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 20 Jan 2026 10:19:12 -0800 (PST) Message-ID: Subject: Re: [PATCH bpf-next v2 04/13] resolve_btfids: Introduce finalize_btf() step From: Eduard Zingerman To: Ihor Solodrai , Alexei Starovoitov , Daniel Borkmann , Andrii Nakryiko , Martin KaFai Lau Cc: Mykyta Yatsenko , Tejun Heo , Alan Maguire , Benjamin Tissoires , Jiri Kosina , Amery Hung , bpf@vger.kernel.org, linux-kernel@vger.kernel.org, linux-input@vger.kernel.org, sched-ext@lists.linux.dev Date: Tue, 20 Jan 2026 10:19:10 -0800 In-Reply-To: References: <20260116201700.864797-1-ihor.solodrai@linux.dev> <20260116201700.864797-5-ihor.solodrai@linux.dev> Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable User-Agent: Evolution 3.58.2 (3.58.2-1.fc43) Precedence: bulk X-Mailing-List: sched-ext@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 On Tue, 2026-01-20 at 10:11 -0800, Ihor Solodrai wrote: [...] > > > @@ -1099,12 +1116,22 @@ int main(int argc, const char **argv) > > > if (obj.efile.idlist_shndx =3D=3D -1 || > > > obj.efile.symbols_shndx =3D=3D -1) { > > > pr_debug("Cannot find .BTF_ids or symbols sections, skip symbols r= esolution\n"); > > > - goto dump_btf; > > > + resolve_btfids =3D false; > > > } > > > =20 > > > - if (symbols_collect(&obj)) > > > + if (resolve_btfids) > > > + if (symbols_collect(&obj)) > > > + goto out; > >=20 > > Nit: check obj.efile.idlist_shndx and obj.efile.symbols_shndx inside sy= mbols_collect()? > > To avoid resolve_btfids flag and the `goto dump_btf;` below. >=20 > Hi Eduard, thank you for review. >=20 > The issue is that in case of .BTF_ids section absent we have to skip > some of the steps, specifically: > - symbols_collect() > - sequence between symbols_resolve() and dump_raw_btf_ids() > It's not an exit condition, we still have to do load/dump of the BTF. >=20 > I tried in symbols_collect(): >=20 > if (obj.efile.idlist_shndx =3D=3D -1 || obj.efile.symbols_shndx =3D=3D -= 1) > return 0; >=20 > But then, we either have to do the same check in symbols_resolve() and > co, or maybe store a flag in the struct object. So I decided it's > better to have an explicit flag in the main control flow, instead of > hiding it. For symbols_resolve() is any special logic necessary? I think that `id =3D btf_id__find(root, str);` will just return NULL for every type, thus the whole function would be a noop passing through BTF types once. symbols_patch() will be a noop, as it will attempt traversing empty roots. dump_raw_btf_ids() already returns if there are no .BTF_ids. [...]