From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-3.8 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE, SPF_PASS,URIBL_BLOCKED autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 474EEFA372C for ; Thu, 7 Nov 2019 02:50:15 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 0E31D218AE for ; Thu, 7 Nov 2019 02:50:15 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="jUuAB9/r" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727751AbfKGCuO (ORCPT ); Wed, 6 Nov 2019 21:50:14 -0500 Received: from mail-qt1-f193.google.com ([209.85.160.193]:43854 "EHLO mail-qt1-f193.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727443AbfKGCuO (ORCPT ); Wed, 6 Nov 2019 21:50:14 -0500 Received: by mail-qt1-f193.google.com with SMTP id l24so738357qtp.10; Wed, 06 Nov 2019 18:50:14 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc; bh=9nCvA3gEV01dvB/sO3Fi4X7jcQkZ1f77jKTKksvxLZc=; b=jUuAB9/rt8iADI6nv+Wo0qGjLgM/XMJRlVcIeq+hza2zj6FVDsbDKPldAPbbZbHp7q b8a8CR9pbKCc5X0fQFhxoyaCEnp8ycHGM9j8ZyDumN69KUCewgaUDnY0g4QPSUJ/Fx3Z mk4Hql5JR4PJX+lKFj28kcSstStNY7kpg/igsi/bxjWVRUhb9VVTpJQ7Q2u1AN2N9NEY VQEs18jf//0fC18CN4iLNerND0/CpbXyX2J3ggMOuw9gCExu3tLkqlrr5I0XmzbPbwS9 kdZk8A+UC+Sp6DVaBlScFVykjox1/wEUM1c0hY52qOyNn5N+P1h40jHhO/cGKW74kF1q 41Jw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc; bh=9nCvA3gEV01dvB/sO3Fi4X7jcQkZ1f77jKTKksvxLZc=; b=dKK4JwKoaft9HuZY6ENsd48ezOtdYfzEYegSY6wfS96aCGBf2T+nWmG+f+O1LWK/gE CtfkzFS6BLGZJ0x8kcgxpj3zgMP8xP5GBFL66ASM84OEDrnRxM6Nv1qybhiRNDC0YNJu eEVrDyaUiJL/KUb9n5mkiSezANNRazCGLk3iH5cAGx4jPiXAW5vTc5sf1MH5s2u2CBQy VDTCeTOWy4bfWD8qqR7UU9dp6qjOPdtd9wITck+tReu2dNtqlK1BVimQ5IEhd1gjrVE7 3eaCoxPU+owJd60U5JjZAipN9KlUWnBtDAjmclI/bRBIZZRV9Q1TCithv/9jbAC7U7nz UgwQ== X-Gm-Message-State: APjAAAWizAMqGDibHgPCU3a/m3ituzjA6S6rC3FKiK/Fp+NomIlweBji T5FP7Nhy3S/1WxLLvcey4u9QHRz6lVuINnSbdzM= X-Google-Smtp-Source: APXvYqwdu05cX2LqU0iWzEIyz+ns5lunqe+h4BybMqO7m7/haNsOmwiL1HRSrWMH+JvVml5EYMQyDrIYGr/IalW5n8U= X-Received: by 2002:aed:35e7:: with SMTP id d36mr1440795qte.59.1573095013477; Wed, 06 Nov 2019 18:50:13 -0800 (PST) MIME-Version: 1.0 References: <20191107014639.384014-1-kafai@fb.com> <20191107014645.384662-1-kafai@fb.com> In-Reply-To: <20191107014645.384662-1-kafai@fb.com> From: Andrii Nakryiko Date: Wed, 6 Nov 2019 18:50:02 -0800 Message-ID: Subject: Re: [PATCH v3 bpf-next 3/3] bpf: Add cb access in kfree_skb test To: Martin KaFai Lau Cc: bpf , Networking , Alexei Starovoitov , Daniel Borkmann , David Miller , Kernel Team Content-Type: text/plain; charset="UTF-8" Sender: bpf-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: bpf@vger.kernel.org On Wed, Nov 6, 2019 at 5:47 PM Martin KaFai Lau wrote: > > Access the skb->cb[] in the kfree_skb test. > > Signed-off-by: Martin KaFai Lau > --- Acked-by: Andrii Nakryiko > .../selftests/bpf/prog_tests/kfree_skb.c | 54 +++++++++++++++---- > tools/testing/selftests/bpf/progs/kfree_skb.c | 25 +++++++-- > 2 files changed, 63 insertions(+), 16 deletions(-) > [...] > > + meta.ifindex = _(dev->ifindex); > + meta.cb8_0 = cb8[8]; > + meta.cb32_0 = cb32[2]; Have you tried doing it inside __builtin_preserve_access_index region? Does it fail because of extra allocations against meta? > + > bpf_probe_read_kernel(&pkt_type, sizeof(pkt_type), _(&skb->__pkt_type_offset)); > pkt_type &= 7; > [...]