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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id D2417C761A6 for ; Tue, 28 Mar 2023 07:22:51 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230287AbjC1HWu (ORCPT ); Tue, 28 Mar 2023 03:22:50 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:60252 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229580AbjC1HWr (ORCPT ); Tue, 28 Mar 2023 03:22:47 -0400 Received: from www62.your-server.de (www62.your-server.de [213.133.104.62]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 54EB12D71; Tue, 28 Mar 2023 00:22:44 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=iogearbox.net; s=default2302; h=Content-Transfer-Encoding:Content-Type: In-Reply-To:MIME-Version:Date:Message-ID:From:References:Cc:To:Subject:Sender :Reply-To:Content-ID:Content-Description:Resent-Date:Resent-From: Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID; bh=ESpFu/zHckpILn58+li2ydE8LBfBNpBi5fiR8Kg6sWY=; b=IxAXQFy0FQQAdQdTKk0mKYpnX9 lEAapQeoTCVHKu4trvRm9noBGFumbVqWSVsdq2aPD34GcQCTizaZE8i0g16VgZleOjcDXXksjHzZo ylFc29DahNprPh65xXF0cejoqUrtoipyVK2UsrURMWXrQzP/TRJ+yF0/ui0jXqQ6AXW3vTso1SNMc AArdXJaCVanUlojfI6a4CIVWGE4eb1k53i88UighbkijvX8GBaw6SGzHYmpavT+zls2awasMGhtCk FHu4nuvi7+wmIriAu+g7Vd09x5ajHio3hleiji1e5O1JlF/Ge2nfvCedWm+AJFrjxLtusVU4Y6eF4 wwSqOKAQ==; Received: from sslproxy03.your-server.de ([88.198.220.132]) by www62.your-server.de with esmtpsa (TLS1.3) tls TLS_AES_256_GCM_SHA384 (Exim 4.94.2) (envelope-from ) id 1ph3f8-0006AP-Ej; Tue, 28 Mar 2023 09:22:34 +0200 Received: from [219.59.88.22] (helo=localhost.localdomain) by sslproxy03.your-server.de with esmtpsa (TLSv1.3:TLS_AES_256_GCM_SHA384:256) (Exim 4.92) (envelope-from ) id 1ph3f7-000RIq-JV; Tue, 28 Mar 2023 09:22:34 +0200 Subject: Re: [PATCH v2] loongarch/bpf: Skip speculation barrier opcode, which caused ltp testcase bpf_prog02 to fail To: George Guo Cc: ast@kernel.org, bpf@vger.kernel.org, chenhuacai@kernel.org, kernel@xen0n.name, linux-kbuild@vger.kernel.org, linux-kernel@vger.kernel.org, loongarch@lists.linux.dev, masahiroy@kernel.org, michal.lkml@markovi.net, ndesaulniers@google.com, hengqi.chen@gmail.com, yangtiezhu@loongson.cn, tangyouling@loongson.cn References: <20230328071335.2664966-1-guodongtai@kylinos.cn> From: Daniel Borkmann Message-ID: Date: Tue, 28 Mar 2023 09:22:24 +0200 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:60.0) Gecko/20100101 Thunderbird/60.7.2 MIME-Version: 1.0 In-Reply-To: <20230328071335.2664966-1-guodongtai@kylinos.cn> Content-Type: text/plain; charset=utf-8; format=flowed Content-Language: en-US Content-Transfer-Encoding: 7bit X-Authenticated-Sender: daniel@iogearbox.net X-Virus-Scanned: Clear (ClamAV 0.103.8/26856/Mon Mar 27 09:24:05 2023) Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 3/28/23 9:13 AM, George Guo wrote: > Here just skip the opcode(BPF_ST | BPF_NOSPEC) that has no couterpart to the loongarch. > > To verify, use ltp testcase: > > Without this patch: > $ ./bpf_prog02 > ... ... > bpf_common.c:123: TBROK: Failed verification: ??? (524) > > Summary: > passed 0 > failed 0 > broken 1 > skipped 0 > warnings 0 > > With this patch: > $ ./bpf_prog02 > ... ... > Summary: > passed 0 > failed 0 > broken 0 > skipped 0 > warnings 0 > > Signed-off-by: George Guo > > --- > Changelog: > v2: > - place it to build_insn > - add printing for skipping bpf_jit the opcode > --- > arch/loongarch/net/bpf_jit.c | 5 +++++ > 1 file changed, 5 insertions(+) > > diff --git a/arch/loongarch/net/bpf_jit.c b/arch/loongarch/net/bpf_jit.c > index 288003a9f0ca..d3c6b1c4ccbb 100644 > --- a/arch/loongarch/net/bpf_jit.c > +++ b/arch/loongarch/net/bpf_jit.c > @@ -1022,6 +1022,11 @@ static int build_insn(const struct bpf_insn *insn, struct jit_ctx *ctx, bool ext > emit_atomic(insn, ctx); > break; > > + /* Speculation barrier */ > + case BPF_ST | BPF_NOSPEC: > + pr_info_once("bpf_jit: skip speculation barrier opcode %0x2x\n", code); > + break; Thanks that looks better. Question to LoongArch folks (Cc): There is no equivalent to a speculation barrier here, correct? Either way, I think the pr_info_once() can just be removed given there is little value for a users to have this in the kernel log. I can take care of this while applying, that's fine. > default: > pr_err("bpf_jit: unknown opcode %02x\n", code); > return -EINVAL; >