From patchwork Tue Dec 14 14:03:59 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Christoph Hellwig X-Patchwork-Id: 12676145 X-Patchwork-Delegate: bpf@iogearbox.net 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 8D4EEC4332F for ; Tue, 14 Dec 2021 14:04:23 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230374AbhLNOEW (ORCPT ); Tue, 14 Dec 2021 09:04:22 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:54846 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229744AbhLNOEV (ORCPT ); Tue, 14 Dec 2021 09:04:21 -0500 Received: from casper.infradead.org (casper.infradead.org [IPv6:2001:8b0:10b:1236::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 95E8EC061574; Tue, 14 Dec 2021 06:04:21 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=casper.20170209; h=Content-Transfer-Encoding:MIME-Version: References:In-Reply-To:Message-Id:Date:Subject:Cc:To:From:Sender:Reply-To: Content-Type:Content-ID:Content-Description; bh=c3sVg+FOnnrAjIuYNGgmpnKM7+jMk1UCUDYyQOig0Cg=; b=lqYkVhyuYv4cjQ7UZO7XX5oyVy JCC4ZXdLn0MQ1ex/UAn+lzDDlUuzInBZpEK4CJLYyQE8eZDo4BFUZbzV+fr9sGXXFJCQPrVRliHHk x0N4ORjY5JJEdCDrjKYawp7D/dZVMMrkHLnWxu1I8TPkOiWxlw19MW5TGYGwNwjX4tGerJtxFH5aE Wmbdf4l8/lGukKqSz8i6zzkOwnbvzJmK1kEF2V51ejFjig+dAYQATo57guxEvMgCqHQK1c7NH5h7Q 9BVGTgfWMxhWYaBTm8/EPcz20rflxxErv14CjmWhwqi2yXvowdVTB62sC9ImpZePUzkF6Ib94hHfK bgL5Mi5g==; Received: from [2001:4bb8:180:a1c8:4ccb:3bf7:77a2:141f] (helo=localhost) by casper.infradead.org with esmtpsa (Exim 4.94.2 #2 (Red Hat Linux)) id 1mx8PV-00DlVH-Sc; Tue, 14 Dec 2021 14:04:06 +0000 From: Christoph Hellwig To: Jonathan Corbet , Alexei Starovoitov , Daniel Borkmann , Andrii Nakryiko Cc: Martin KaFai Lau , Song Liu , Yonghong Song , John Fastabend , KP Singh , linux-doc@vger.kernel.org, netdev@vger.kernel.org, bpf@vger.kernel.org Subject: [PATCH 1/4] bpf, docs: Fix verifier reference Date: Tue, 14 Dec 2021 15:03:59 +0100 Message-Id: <20211214140402.288101-2-hch@lst.de> X-Mailer: git-send-email 2.30.2 In-Reply-To: <20211214140402.288101-1-hch@lst.de> References: <20211214140402.288101-1-hch@lst.de> MIME-Version: 1.0 X-SRS-Rewrite: SMTP reverse-path rewritten from by casper.infradead.org. See http://www.infradead.org/rpr.html Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org X-Patchwork-Delegate: bpf@iogearbox.net Use normal RST file reference instead of linkage copied from the old filter.rst document that does not actually work when using HTML output. Signed-off-by: Christoph Hellwig --- Documentation/bpf/instruction-set.rst | 7 ++----- 1 file changed, 2 insertions(+), 5 deletions(-) diff --git a/Documentation/bpf/instruction-set.rst b/Documentation/bpf/instruction-set.rst index fa7cba59031e5..fa469078301be 100644 --- a/Documentation/bpf/instruction-set.rst +++ b/Documentation/bpf/instruction-set.rst @@ -203,7 +203,7 @@ Some core changes of the eBPF format from classic BPF: bpf_exit After the call the registers R1-R5 contain junk values and cannot be read. - An in-kernel `eBPF verifier`_ is used to validate eBPF programs. + An in-kernel verifier.rst is used to validate eBPF programs. Also in the new design, eBPF is limited to 4096 insns, which means that any program will terminate quickly and will only call a fixed number of kernel @@ -234,7 +234,7 @@ optimizations, socket filters and seccomp are using it as assembler. Tracing filters may use it as assembler to generate code from kernel. In kernel usage may not be bounded by security considerations, since generated eBPF code may be optimizing internal code path and not being exposed to the user space. -Safety of eBPF can come from the `eBPF verifier`_. In such use cases as +Safety of eBPF can come from the verifier.rst. In such use cases as described, it may be used as safe instruction set. Just like the original BPF, eBPF runs within a controlled environment, @@ -462,6 +462,3 @@ of two consecutive ``struct bpf_insn`` 8-byte blocks and interpreted as single instruction that loads 64-bit immediate value into a dst_reg. Classic BPF has similar instruction: ``BPF_LD | BPF_W | BPF_IMM`` which loads 32-bit immediate value into a register. - -.. Links: -.. _eBPF verifier: verifiers.rst