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=-8.2 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_2 autolearn=ham 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 4824CC2D0DA for ; Wed, 25 Dec 2019 09:42:12 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 1166720722 for ; Wed, 25 Dec 2019 09:42:12 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=Synaptics.onmicrosoft.com header.i=@Synaptics.onmicrosoft.com header.b="mdoO1Ok+" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726106AbfLYJmL (ORCPT ); Wed, 25 Dec 2019 04:42:11 -0500 Received: from mail-bn8nam11on2073.outbound.protection.outlook.com ([40.107.236.73]:63489 "EHLO NAM11-BN8-obe.outbound.protection.outlook.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1726025AbfLYJmL (ORCPT ); Wed, 25 Dec 2019 04:42:11 -0500 ARC-Seal: i=1; a=rsa-sha256; s=arcselector9901; d=microsoft.com; cv=none; b=GmDzoU6LfS9861GwusgyfGrjrU3lbkGZE+BEEsyfqcElBcBcq3SIovvoI8h4RtPiy4xTonIT5u5wSzqUTXtARAICkQbidXTLlRRcv9jWLx7PoMmDlkILqT+p9CbxFhSV5y+VuLqwJuGpUVN+zGgMwK5gsYDKBmdDKG9LlhgPHYDwxEr5DJa+6N6Hx4OMW7+bHWlqdDBa6YudH70vHfFf59Qrvhe/sfGnYMUVr9tlNhcNbdXMD3VObn6HROG6C1DyErazthygLUd2q7j1sXjsoo0++DHcjOCqs8qAkqlk/WFuveMyCT8ZdNaU+aoxWnLSprvy0ZLp+rzV/0n1z5L8Sg== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=microsoft.com; s=arcselector9901; h=From:Date:Subject:Message-ID:Content-Type:MIME-Version:X-MS-Exchange-SenderADCheck; bh=ILbzOurn3R6bsV0bRaBNRAdQHJ40b9HcElY3vUMCP8M=; b=FlNjpLEkMnrZRYmQ3Xd2ihGjAt97roUNI8rISZXk4rNXGn0IYSk3RZkPbntfc9WsbSmGWYpJXsn7wmewwjBIdbphTLNFdGwG2mQI2gLz3KRIYR0PBWDy2lxoFpITMbKDjVZCzgpI+Lif/MIAZrsWj3776svZ2yKt60teUsOJogz0ZJ9l7qQC6Vfi5w/99RyPDNaBEdaXlm2TXefSzKqFf/0y6tvZu/yiQsq706gi6fCMXhfykjsh+JZ3DWCTLB2a7kum3minon5zIZZuX7UK0Z/gB3uLo0qQYAkJ31fwfPK4ADDh2AGKewkCB0X172BgWBor+TfRPV9fFlMKQ9zV2w== ARC-Authentication-Results: i=1; mx.microsoft.com 1; spf=pass smtp.mailfrom=synaptics.com; dmarc=pass action=none header.from=synaptics.com; dkim=pass header.d=synaptics.com; arc=none DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=Synaptics.onmicrosoft.com; s=selector2-Synaptics-onmicrosoft-com; h=From:Date:Subject:Message-ID:Content-Type:MIME-Version:X-MS-Exchange-SenderADCheck; bh=ILbzOurn3R6bsV0bRaBNRAdQHJ40b9HcElY3vUMCP8M=; b=mdoO1Ok+O6dK+kPx9NkC7cOAOp+PVixC6acesVQdcdv2lS5us+VdFxjZfD6ZirQWaDolDT+K6dQT3jsgQSgSB1XQMnEn8DAyCwnl+cJCkBKor4LFgGkaGYsQxPLvRdE6WV0pldhD3ZKYXkraX20sTFBeRJ5am0LbKEm5H+qKyhE= Received: from BYAPR03MB4773.namprd03.prod.outlook.com (20.179.93.213) by BYAPR03MB4661.namprd03.prod.outlook.com (20.179.91.218) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.20.2581.11; Wed, 25 Dec 2019 09:42:07 +0000 Received: from BYAPR03MB4773.namprd03.prod.outlook.com ([fe80::708d:91cc:79a7:9b9a]) by BYAPR03MB4773.namprd03.prod.outlook.com ([fe80::708d:91cc:79a7:9b9a%6]) with mapi id 15.20.2559.017; Wed, 25 Dec 2019 09:42:07 +0000 Received: from xhacker.debian (124.74.246.114) by TYAPR01CA0196.jpnprd01.prod.outlook.com (2603:1096:404:29::16) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.20.2581.11 via Frontend Transport; Wed, 25 Dec 2019 09:42:04 +0000 From: Jisheng Zhang To: Catalin Marinas , Will Deacon , Steven Rostedt , Ingo Molnar , "Naveen N. Rao" , Anil S Keshavamurthy , "David S. Miller" , Masami Hiramatsu , Mark Rutland , Jonathan Corbet CC: "linux-kernel@vger.kernel.org" , "linux-arm-kernel@lists.infradead.org" , "linux-doc@vger.kernel.org" Subject: [PATCH v7 1/3] kprobes/ftrace: Use ftrace_location() when [dis]arming probes Thread-Topic: [PATCH v7 1/3] kprobes/ftrace: Use ftrace_location() when [dis]arming probes Thread-Index: AQHVuweSj3f0oMePuk6TgrRxmwYaVQ== Date: Wed, 25 Dec 2019 09:42:07 +0000 Message-ID: <20191225172752.70be1dc1@xhacker.debian> References: <20191225172625.69811b3e@xhacker.debian> In-Reply-To: <20191225172625.69811b3e@xhacker.debian> Accept-Language: en-US Content-Language: en-US X-MS-Has-Attach: X-MS-TNEF-Correlator: x-originating-ip: [124.74.246.114] x-clientproxiedby: TYAPR01CA0196.jpnprd01.prod.outlook.com (2603:1096:404:29::16) To BYAPR03MB4773.namprd03.prod.outlook.com (2603:10b6:a03:139::21) authentication-results: spf=none (sender IP is ) smtp.mailfrom=Jisheng.Zhang@synaptics.com; x-ms-exchange-messagesentrepresentingtype: 1 x-mailer: Claws Mail 3.17.4 (GTK+ 2.24.32; x86_64-pc-linux-gnu) x-ms-publictraffictype: Email x-ms-office365-filtering-correlation-id: 0fce643c-9505-4d9c-7898-08d7891eb4e6 x-ms-traffictypediagnostic: BYAPR03MB4661: x-microsoft-antispam-prvs: x-ms-oob-tlc-oobclassifiers: OLM:9508; x-forefront-prvs: 02622CEF0A x-forefront-antispam-report: SFV:NSPM;SFS:(10009020)(136003)(346002)(376002)(396003)(39850400004)(366004)(189003)(199004)(1076003)(81166006)(26005)(81156014)(55016002)(9686003)(8936002)(4326008)(186003)(7696005)(66946007)(86362001)(16526019)(8676002)(478600001)(52116002)(66556008)(6506007)(66446008)(64756008)(66476007)(956004)(110136005)(54906003)(7416002)(316002)(5660300002)(2906002)(71200400001)(921003)(1121003)(39210200001);DIR:OUT;SFP:1101;SCL:1;SRVR:BYAPR03MB4661;H:BYAPR03MB4773.namprd03.prod.outlook.com;FPR:;SPF:None;LANG:en;PTR:InfoNoRecords;MX:1;A:0; received-spf: None (protection.outlook.com: synaptics.com does not designate permitted sender hosts) x-ms-exchange-senderadcheck: 1 x-microsoft-antispam: BCL:0; x-microsoft-antispam-message-info: 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 x-ms-exchange-transport-forked: True Content-Type: text/plain; charset="us-ascii" Content-ID: Content-Transfer-Encoding: quoted-printable MIME-Version: 1.0 X-OriginatorOrg: synaptics.com X-MS-Exchange-CrossTenant-Network-Message-Id: 0fce643c-9505-4d9c-7898-08d7891eb4e6 X-MS-Exchange-CrossTenant-originalarrivaltime: 25 Dec 2019 09:42:07.5320 (UTC) X-MS-Exchange-CrossTenant-fromentityheader: Hosted X-MS-Exchange-CrossTenant-id: 335d1fbc-2124-4173-9863-17e7051a2a0e X-MS-Exchange-CrossTenant-mailboxtype: HOSTED X-MS-Exchange-CrossTenant-userprincipalname: pMJT/VD22Zhwy7J2nasGbiPwPwvKs/0auBK8J+jYjxEnY3P/yBSIA2TxKNi0SlJPvLwH/dRU0fGYABQ/8GJ18Q== X-MS-Exchange-Transport-CrossTenantHeadersStamped: BYAPR03MB4661 Sender: linux-doc-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-doc@vger.kernel.org Ftrace location could include more than a single instruction in case of some architectures (powerpc64, for now). In this case, kprobe is permitted on any of those instructions, and uses ftrace infrastructure for functioning. However, [dis]arm_kprobe_ftrace() uses the kprobe address when setting up ftrace filter IP. This won't work if the address points to any instruction apart from the one that has a branch to _mcount(). To resolve this, have [dis]arm_kprobe_ftrace() use ftrace_function() to identify the filter IP. Signed-off-by: Naveen N. Rao Acked-by: Masami Hiramatsu --- kernel/kprobes.c | 8 +++++--- 1 file changed, 5 insertions(+), 3 deletions(-) diff --git a/kernel/kprobes.c b/kernel/kprobes.c index 53534aa258a6..5c630b424e3a 100644 --- a/kernel/kprobes.c +++ b/kernel/kprobes.c @@ -986,9 +986,10 @@ static int prepare_kprobe(struct kprobe *p) static int __arm_kprobe_ftrace(struct kprobe *p, struct ftrace_ops *ops, int *cnt) { + unsigned long ftrace_ip =3D ftrace_location((unsigned long)p->addr); int ret =3D 0; =20 - ret =3D ftrace_set_filter_ip(ops, (unsigned long)p->addr, 0, 0); + ret =3D ftrace_set_filter_ip(ops, ftrace_ip, 0, 0); if (ret) { pr_debug("Failed to arm kprobe-ftrace at %pS (%d)\n", p->addr, ret); @@ -1011,7 +1012,7 @@ static int __arm_kprobe_ftrace(struct kprobe *p, stru= ct ftrace_ops *ops, * At this point, sinec ops is not registered, we should be sefe from * registering empty filter. */ - ftrace_set_filter_ip(ops, (unsigned long)p->addr, 1, 0); + ftrace_set_filter_ip(ops, ftrace_ip, 1, 0); return ret; } =20 @@ -1028,6 +1029,7 @@ static int arm_kprobe_ftrace(struct kprobe *p) static int __disarm_kprobe_ftrace(struct kprobe *p, struct ftrace_ops *ops= , int *cnt) { + unsigned long ftrace_ip =3D ftrace_location((unsigned long)p->addr); int ret =3D 0; =20 if (*cnt =3D=3D 1) { @@ -1038,7 +1040,7 @@ static int __disarm_kprobe_ftrace(struct kprobe *p, s= truct ftrace_ops *ops, =20 (*cnt)--; =20 - ret =3D ftrace_set_filter_ip(ops, (unsigned long)p->addr, 1, 0); + ret =3D ftrace_set_filter_ip(ops, ftrace_ip, 1, 0); WARN_ONCE(ret < 0, "Failed to disarm kprobe-ftrace at %pS (%d)\n", p->addr, ret); return ret; --=20 2.24.1