From patchwork Wed Jun 1 17:57:44 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Song Liu X-Patchwork-Id: 12867116 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 5DE32CCA47A for ; Wed, 1 Jun 2022 17:58:13 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1356489AbiFAR6L convert rfc822-to-8bit (ORCPT ); Wed, 1 Jun 2022 13:58:11 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:51690 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1344215AbiFAR6J (ORCPT ); Wed, 1 Jun 2022 13:58:09 -0400 Received: from mx0b-00082601.pphosted.com (mx0b-00082601.pphosted.com [67.231.153.30]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 1E4C4996BB for ; Wed, 1 Jun 2022 10:58:07 -0700 (PDT) Received: from pps.filterd (m0109331.ppops.net [127.0.0.1]) by mx0a-00082601.pphosted.com (8.17.1.5/8.17.1.5) with ESMTP id 251E8WnP020519 for ; Wed, 1 Jun 2022 10:58:07 -0700 Received: from maileast.thefacebook.com ([163.114.130.16]) by mx0a-00082601.pphosted.com (PPS) with ESMTPS id 3ge9m2hpqx-3 (version=TLSv1.2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128 verify=NOT) for ; Wed, 01 Jun 2022 10:58:07 -0700 Received: from twshared19572.14.frc2.facebook.com (2620:10d:c0a8:1b::d) by mail.thefacebook.com (2620:10d:c0a8:83::4) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2375.28; Wed, 1 Jun 2022 10:58:05 -0700 Received: by devbig932.frc1.facebook.com (Postfix, from userid 4523) id 05F078603CAF; Wed, 1 Jun 2022 10:57:56 -0700 (PDT) From: Song Liu To: , , CC: , , , , , , Song Liu Subject: [PATCH bpf-next 0/5] ftrace: host klp and bpf trampoline together Date: Wed, 1 Jun 2022 10:57:44 -0700 Message-ID: <20220601175749.3071572-1-song@kernel.org> X-Mailer: git-send-email 2.30.2 MIME-Version: 1.0 X-FB-Internal: Safe X-Proofpoint-GUID: aO0LqPKF9U38PhbkVKDjLvsxYBrPrzYJ X-Proofpoint-ORIG-GUID: aO0LqPKF9U38PhbkVKDjLvsxYBrPrzYJ X-Proofpoint-Virus-Version: vendor=baseguard engine=ICAP:2.0.205,Aquarius:18.0.874,Hydra:6.0.517,FMLib:17.11.64.514 definitions=2022-06-01_06,2022-06-01_01,2022-02-23_01 Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org X-Patchwork-Delegate: bpf@iogearbox.net Kernel Live Patch (livepatch, or klp) and bpf trampoline are important features for modern systems. This set allows the two to work on the same kernel function as the same time. live patch uses ftrace with IPMODIFY, while bpf trampoline use direct ftrace. Existing policy does not allow the two to attach to the same kernel function. This is changed by fine tuning ftrace IPMODIFY policy, and allows one non-DIRECT IPMODIFY ftrace_ops and one non-IPMODIFY DIRECT ftrace_ops on the same kernel function at the same time. Please see 3/5 for more details on this. Note that, one of the constraint here is to let bpf trampoline use direct call when it is not working on the same function as live patch. This is achieved by allowing ftrace code to ask bpf trampoline to make changes. Jiri Olsa (1): bpf, x64: Allow to use caller address from stack Song Liu (4): ftrace: allow customized flags for ftrace_direct_multi ftrace_ops ftrace: add modify_ftrace_direct_multi_nolock ftrace: introduce FTRACE_OPS_FL_SHARE_IPMODIFY bpf: trampoline: support FTRACE_OPS_FL_SHARE_IPMODIFY arch/x86/net/bpf_jit_comp.c | 13 +- include/linux/bpf.h | 8 ++ include/linux/ftrace.h | 79 +++++++++++ kernel/bpf/trampoline.c | 100 ++++++++++++-- kernel/trace/ftrace.c | 269 +++++++++++++++++++++++++++++++----- 5 files changed, 416 insertions(+), 53 deletions(-) --- 2.30.2