From patchwork Thu Apr 20 03:27:34 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Feng zhou X-Patchwork-Id: 675771 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id BCF0AC77B75 for ; Thu, 20 Apr 2023 03:28:31 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233769AbjDTD23 (ORCPT ); Wed, 19 Apr 2023 23:28:29 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:36504 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S233702AbjDTD2X (ORCPT ); Wed, 19 Apr 2023 23:28:23 -0400 Received: from mail-pf1-x429.google.com (mail-pf1-x429.google.com [IPv6:2607:f8b0:4864:20::429]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id E9D494202 for ; Wed, 19 Apr 2023 20:27:56 -0700 (PDT) Received: by mail-pf1-x429.google.com with SMTP id d2e1a72fcca58-63b4e5fdb1eso714941b3a.1 for ; Wed, 19 Apr 2023 20:27:56 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=bytedance.com; s=google; t=1681961276; x=1684553276; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:from:to:cc:subject:date :message-id:reply-to; bh=hr7bhkX+Epn2YWYx/+oT337obKjgENzwcgRHzhBp9VI=; b=EbJ7DiX0KNLClu6JNpZIDUdsu5ZAfzUcUtofGd3c7gYYeF16zc/59GXJ+AutZPz5w3 1ifFTsK5hJK7jS8Yuwo7Jpyx5xPPQBukFkmUdFtOl7Q+AjoYuvx5dbhYnTTITWFdLbT0 0yQKRpLKV/NLt/a9TXPz/ywKmiu4fth5/3NewCfewonuQbTDHwV12xSpaKQu3zXBdLTK Wkanbypedh5FCjD5x9rM26Np8iyWJ5A6WTwsT0eUl7SY1+Mb/AXTqtug1T3xcMgQl0nK yW1wBdq39B32F1H77/uS5PhpH+H1TGtEQ217Ncm+uuavogm6WqfJlu1T+jxqmG4+Bqhw b38A== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20221208; t=1681961276; x=1684553276; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:x-gm-message-state:from:to:cc :subject:date:message-id:reply-to; bh=hr7bhkX+Epn2YWYx/+oT337obKjgENzwcgRHzhBp9VI=; b=NrPHfmhsSbhuh1eT71QE96hPAxkgbSs4HmN9RcWcFPmp/nUbJY0WOXSv4Vo3h+C+b+ z/PKEtSCE2Sc1YF7/d2RAKwD2JON8DRueHXsvXNf7fNDCdiGnZYLKfENclRbrI4VhoSs jPhe9vkRQWIXqmZF3Oedg0iyRM3uGsJCE9X9mISZkqQ2c/klq73n8cDdhROlPGQKfEKR F6lnEEtvm/zjqzqQmKX4GmuDGQtAUfGZO6GFJc59ij4o5fSGi2rDu0gAjrId8E/nasVX 2x1HwRf+dzUg3lNrH2oNM9ra3MGY2tqSpF6VxLTrW3FpZd7MRz1TJq1X4LV4aNHIsNQI vBZQ== X-Gm-Message-State: AAQBX9d7VUrFFHxR8WPy/w8wB+RwtiOz/OPQofiWPfzMpK1Dl2RRcPcq Nj/E98l6n2ykEsNHequv1Yn8WQ== X-Google-Smtp-Source: AKy350Zzlox3kqFQwaEZJ1yWV/Qr9yqOXqttJ3x49/9gX0Cj/UedEau5H5gSR+U9pHNT8o+cBv2Pjw== X-Received: by 2002:a05:6a00:189c:b0:626:2984:8a76 with SMTP id x28-20020a056a00189c00b0062629848a76mr7091693pfh.34.1681961276413; Wed, 19 Apr 2023 20:27:56 -0700 (PDT) Received: from C02F52LSML85.bytedance.net ([139.177.225.254]) by smtp.gmail.com with ESMTPSA id z15-20020a655a4f000000b00517abaac366sm115231pgs.74.2023.04.19.20.27.48 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 19 Apr 2023 20:27:56 -0700 (PDT) From: Feng zhou To: martin.lau@linux.dev, ast@kernel.org, daniel@iogearbox.net, andrii@kernel.org, song@kernel.org, yhs@fb.com, john.fastabend@gmail.com, kpsingh@kernel.org, sdf@google.com, haoluo@google.com, jolsa@kernel.org, davem@davemloft.net, edumazet@google.com, kuba@kernel.org, pabeni@redhat.com, mykolal@fb.com, shuah@kernel.org Cc: bpf@vger.kernel.org, linux-kernel@vger.kernel.org, netdev@vger.kernel.org, linux-kselftest@vger.kernel.org, yangzhenze@bytedance.com, wangdongdong.6@bytedance.com, zhouchengming@bytedance.com, zhoufeng.zf@bytedance.com Subject: [PATCH bpf-next v2 1/2] bpf: support access variable length array of integer type Date: Thu, 20 Apr 2023 11:27:34 +0800 Message-Id: <20230420032735.27760-2-zhoufeng.zf@bytedance.com> X-Mailer: git-send-email 2.39.2 (Apple Git-143) In-Reply-To: <20230420032735.27760-1-zhoufeng.zf@bytedance.com> References: <20230420032735.27760-1-zhoufeng.zf@bytedance.com> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-kselftest@vger.kernel.org From: Feng Zhou After this commit: bpf: Support variable length array in tracing programs (9c5f8a1008a1) Trace programs can access variable length array, but for structure type. This patch adds support for integer type. Example: Hook load_balance struct sched_domain { ... unsigned long span[]; } The access: sd->span[0]. Co-developed-by: Chengming Zhou Signed-off-by: Chengming Zhou Signed-off-by: Feng Zhou --- kernel/bpf/btf.c | 8 +++++--- 1 file changed, 5 insertions(+), 3 deletions(-) diff --git a/kernel/bpf/btf.c b/kernel/bpf/btf.c index 027f9f8a3551..a0887ee44e89 100644 --- a/kernel/bpf/btf.c +++ b/kernel/bpf/btf.c @@ -6157,11 +6157,13 @@ static int btf_struct_walk(struct bpf_verifier_log *log, const struct btf *btf, if (off < moff) goto error; - /* Only allow structure for now, can be relaxed for - * other types later. - */ + /* allow structure and integer */ t = btf_type_skip_modifiers(btf, array_elem->type, NULL); + + if (btf_type_is_int(t)) + return WALK_SCALAR; + if (!btf_type_is_struct(t)) goto error;