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=-0.8 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, SPF_PASS 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 D6D99C433F5 for ; Fri, 7 Sep 2018 00:58:13 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 709F72083D for ; Fri, 7 Sep 2018 00:58:13 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=microsoft.com header.i=@microsoft.com header.b="W/oiRtn+" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 709F72083D Authentication-Results: mail.kernel.org; dmarc=fail (p=reject dis=none) header.from=microsoft.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729598AbeIGFgW (ORCPT ); Fri, 7 Sep 2018 01:36:22 -0400 Received: from mail-eopbgr690126.outbound.protection.outlook.com ([40.107.69.126]:51988 "EHLO NAM04-CO1-obe.outbound.protection.outlook.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1726695AbeIGFPO (ORCPT ); Fri, 7 Sep 2018 01:15:14 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=microsoft.com; s=selector1; h=From:Date:Subject:Message-ID:Content-Type:MIME-Version:X-MS-Exchange-SenderADCheck; bh=Fc5lYW519/9VCzEPyteoNxpHnnsCAG1TaQCXiSpuKY0=; b=W/oiRtn+TjsRndBa7s8i6p5k7fCnfm+j3iRm8bvAC2LWlpTnC4rnAPHoAFIhrLe2OFOP4/067j3lOvOOTpbNTk1NPfDvbeYqLQ3Q+b8TzwPRpYoLL2Z1MP5Pq+c5RSKlSDwsdQH2djmPCsCEv+WYthFcb9Bc0VxQhlfuW/xq+JM= Received: from CY4PR21MB0776.namprd21.prod.outlook.com (10.173.192.22) by CY4PR21MB0773.namprd21.prod.outlook.com (10.173.192.19) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.20.1143.1; Fri, 7 Sep 2018 00:36:52 +0000 Received: from CY4PR21MB0776.namprd21.prod.outlook.com ([fe80::7c3a:eea8:1391:1611]) by CY4PR21MB0776.namprd21.prod.outlook.com ([fe80::7c3a:eea8:1391:1611%7]) with mapi id 15.20.1143.008; Fri, 7 Sep 2018 00:36:52 +0000 From: Sasha Levin To: "stable@vger.kernel.org" , "linux-kernel@vger.kernel.org" CC: Sandipan Das , Jiri Olsa , Maynard Johnson , "Naveen N . Rao" , Ravi Bangoria , Sukadev Bhattiprolu , Arnaldo Carvalho de Melo , Sasha Levin Subject: [PATCH AUTOSEL 4.18 46/88] perf powerpc: Fix callchain ip filtering when return address is in a register Thread-Topic: [PATCH AUTOSEL 4.18 46/88] perf powerpc: Fix callchain ip filtering when return address is in a register Thread-Index: AQHURkLPrFKVsFVXZkmIh9rRJlIqIw== Date: Fri, 7 Sep 2018 00:36:26 +0000 Message-ID: <20180907003547.57567-46-alexander.levin@microsoft.com> References: <20180907003547.57567-1-alexander.levin@microsoft.com> In-Reply-To: <20180907003547.57567-1-alexander.levin@microsoft.com> Accept-Language: en-US Content-Language: en-US X-MS-Has-Attach: X-MS-TNEF-Correlator: x-originating-ip: [52.168.54.252] x-ms-publictraffictype: Email x-microsoft-exchange-diagnostics: 1;CY4PR21MB0773;6:gpQ0nWZofEkxQw+0MRQtCZwUfoCWq6TZ6EwpdLOfgZD512farMqX+w6MMGW4EmZtxUu51dscihdxbPP+tm+ef2IijUJn8/GsOA2sWHh/NeQ+4v7aoBTG/Fsc4EpHeiLypaTmE49LOgAQZBCUDoMhPya+lCzc/AeALAexqftrqKlol500PkHsmHVFxWzzvSrgIm0MWJeCjRdsrK9Jf3nfwe1Oz2TMLi/bafK8ehA4mFJMQ6YKlaxu79Ze89qm5zvBvHI7sGuKHujo5qvyScGN2/A1FEXQJXCz3wjC8eXECV1l24OuDKWEo/33Ai4n8RjlAASfKDDZELj8dPmaYRONJYj8+L2vsIOjSmBWI5N55S5HFFggMwWaAcewd5Bjf6rA/fdYx/4s5V1jvovFllPHB7P3/C9EUg39w6o+l9x8tV0MCqQB3APZN+aSr9ejpCpwnPmAC+DJSZxWZqLq5OxsmA==;5:4FMykImjif7QZtYnINRxA5fwxE0cRpTxkf6xIjdC2zGzZTon5cH3qXTzgkVJdlch8MXOv2Qg8n7zieS/Y1ExGpGeuWqqkfAkZNmJTJncRb+N+108brKdIiMEP3M1SNrsGdJums3jdukX64VAncPVFR3gwGqnxTTA7HPe4SQnGtc=;7:CuYao1/Ak1zLCY7eTHwLeMT9evROAB8B0QYqPHEJjbua6hJQoehRnWEb5O3QjriWx5IfUbZJmO2waqTC27aGxECuFmwGVZn7Z5jcPKXQR++Uq9WXsE+xiEyv1LwWMYJWhu7e95O8MKo7qNYDtT9gbiaX9044VrKmtniysj+5FX+hLhjr244tbtrpNbtHXvre3ulj2f6aGu9a0OUDkPzDzfSiSPvD2AzMlb21hDnVE1qjFevje6EdOP57dst6UISn x-ms-office365-filtering-correlation-id: 242fc111-ecfd-48ec-23e7-08d6145a0176 x-ms-office365-filtering-ht: Tenant x-microsoft-antispam: BCL:0;PCL:0;RULEID:(7020095)(4652040)(8989137)(4534165)(4627221)(201703031133081)(201702281549075)(8990107)(5600074)(711020)(4618075)(2017052603328)(7193020);SRVR:CY4PR21MB0773; x-ms-traffictypediagnostic: CY4PR21MB0773: authentication-results: spf=none (sender IP is ) smtp.mailfrom=Alexander.Levin@microsoft.com; x-microsoft-antispam-prvs: x-exchange-antispam-report-test: UriScan:(28532068793085)(89211679590171)(42068640409301)(274839183919467)(104084551191319); x-ms-exchange-senderadcheck: 1 x-exchange-antispam-report-cfa-test: BCL:0;PCL:0;RULEID:(8211001083)(6040522)(2401047)(8121501046)(5005006)(3231344)(944501410)(52105095)(2018427008)(93006095)(93001095)(10201501046)(3002001)(6055026)(149027)(150027)(6041310)(201703131423095)(201702281528075)(20161123555045)(201703061421075)(201703061406153)(20161123560045)(20161123564045)(20161123558120)(20161123562045)(201708071742011)(7699049)(76991033);SRVR:CY4PR21MB0773;BCL:0;PCL:0;RULEID:;SRVR:CY4PR21MB0773; x-forefront-prvs: 07880C4932 x-forefront-antispam-report: SFV:NSPM;SFS:(10019020)(366004)(136003)(39860400002)(346002)(376002)(396003)(189003)(199004)(8676002)(5660300001)(106356001)(6436002)(25786009)(110136005)(54906003)(6506007)(105586002)(2906002)(486006)(53936002)(446003)(6306002)(2616005)(476003)(4326008)(6666003)(11346002)(5250100002)(107886003)(2501003)(86612001)(97736004)(6512007)(966005)(478600001)(3846002)(72206003)(6116002)(10290500003)(76176011)(68736007)(14454004)(1076002)(66066001)(26005)(575784001)(6486002)(99286004)(8936002)(36756003)(81166006)(86362001)(256004)(102836004)(81156014)(305945005)(186003)(22452003)(2900100001)(7736002)(10090500001)(316002)(217873002);DIR:OUT;SFP:1102;SCL:1;SRVR:CY4PR21MB0773;H:CY4PR21MB0776.namprd21.prod.outlook.com;FPR:;SPF:None;LANG:en;PTR:InfoNoRecords;MX:1;A:1; received-spf: None (protection.outlook.com: microsoft.com does not designate permitted sender hosts) x-microsoft-antispam-message-info: mn3ks8I4Z4Wdi8XM3NiNYDocwlM/ikW9GfBAY482t9GFC2U/JxeSlncFhUi24SmLddLe//7U+F8TpgJGZxf179bLFIugKJchbv9VZ1KK4P9sKad+eSbOd6N5zRP67S97HAw1WG+i3qoHdMZQ5J7tQ8SvhN3GVK8h8l6Z1s4PwepGX4r8h+QvHm9/O1vtYWyrnGMPXdYlEUCNgCJx5NLRyU82LkeLKfD1OePmtmFfjDWvMJNgc+0hNT5NnC9tU2RL2xPfCYUrm5z8vox8+Qat/WXCWidoBbkv+++G7jpfZsirRZp1Y3Q/WZbB19p7Bww441KQXBWnz+5s2DDDfyzbHTzSv56KhUI8nVPxMwFbsfU= spamdiagnosticoutput: 1:99 spamdiagnosticmetadata: NSPM Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable MIME-Version: 1.0 X-OriginatorOrg: microsoft.com X-MS-Exchange-CrossTenant-Network-Message-Id: 242fc111-ecfd-48ec-23e7-08d6145a0176 X-MS-Exchange-CrossTenant-originalarrivaltime: 07 Sep 2018 00:36:26.7132 (UTC) X-MS-Exchange-CrossTenant-fromentityheader: Hosted X-MS-Exchange-CrossTenant-id: 72f988bf-86f1-41af-91ab-2d7cd011db47 X-MS-Exchange-Transport-CrossTenantHeadersStamped: CY4PR21MB0773 Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Sandipan Das [ Upstream commit 9068533e4f470daf2b0f29c71d865990acd8826e ] For powerpc64, perf will filter out the second entry in the callchain, i.e. the LR value, if the return address of the function corresponding to the probed location has already been saved on its caller's stack. The state of the return address is determined using debug information. At any point within a function, if the return address is already saved somewhere, a DWARF expression can tell us about its location. If the return address in still in LR only, no DWARF expression would exist. Typically, the instructions in a function's prologue first copy the LR value to R0 and then pushes R0 on to the stack. If LR has already been copied to R0 but R0 is yet to be pushed to the stack, we can still get a DWARF expression that says that the return address is in R0. This is indicating that getting a DWARF expression for the return address does not guarantee the fact that it has already been saved on the stack. This can be observed on a powerpc64le system running Fedora 27 as shown below. # objdump -d /usr/lib64/libc-2.26.so | less ... 000000000015af20 : 15af20: 0b 00 4c 3c addis r2,r12,11 15af24: e0 c1 42 38 addi r2,r2,-15904 15af28: a6 02 08 7c mflr r0 15af2c: f0 ff c1 fb std r30,-16(r1) 15af30: f8 ff e1 fb std r31,-8(r1) 15af34: 78 1b 7f 7c mr r31,r3 15af38: 78 23 83 7c mr r3,r4 15af3c: 78 2b be 7c mr r30,r5 15af40: 10 00 01 f8 std r0,16(r1) 15af44: c1 ff 21 f8 stdu r1,-64(r1) 15af48: 28 00 81 f8 std r4,40(r1) ... # readelf --debug-dump=3Dframes-interp /usr/lib64/libc-2.26.so | less ... 00027024 0000000000000024 00027028 FDE cie=3D00000000 pc=3D000000000015af= 20..000000000015af88 LOC CFA r30 r31 ra 000000000015af20 r1+0 u u u 000000000015af34 r1+0 c-16 c-8 r0 000000000015af48 r1+64 c-16 c-8 c+16 000000000015af5c r1+0 c-16 c-8 c+16 000000000015af78 r1+0 u u ... # perf probe -x /usr/lib64/libc-2.26.so -a inet_pton+0x18 # perf record -e probe_libc:inet_pton -g ping -6 -c 1 ::1 # perf script Before: ping 2829 [005] 512917.460174: probe_libc:inet_pton: (7fff7e2baf38) 7fff7e2baf38 __GI___inet_pton+0x18 (/usr/lib64/libc-2.26.so) 7fff7e2705b4 getaddrinfo+0x164 (/usr/lib64/libc-2.26.so) 12f152d70 _init+0xbfc (/usr/bin/ping) 7fff7e1836a0 generic_start_main.isra.0+0x140 (/usr/lib64/libc= -2.26.so) 7fff7e183898 __libc_start_main+0xb8 (/usr/lib64/libc-2.26.so) 0 [unknown] ([unknown]) After: ping 2829 [005] 512917.460174: probe_libc:inet_pton: (7fff7e2baf38) 7fff7e2baf38 __GI___inet_pton+0x18 (/usr/lib64/libc-2.26.so) 7fff7e26fa54 gaih_inet.constprop.7+0xf44 (/usr/lib64/libc-2.2= 6.so) 7fff7e2705b4 getaddrinfo+0x164 (/usr/lib64/libc-2.26.so) 12f152d70 _init+0xbfc (/usr/bin/ping) 7fff7e1836a0 generic_start_main.isra.0+0x140 (/usr/lib64/libc= -2.26.so) 7fff7e183898 __libc_start_main+0xb8 (/usr/lib64/libc-2.26.so) 0 [unknown] ([unknown]) Reported-by: Ravi Bangoria Signed-off-by: Sandipan Das Cc: Jiri Olsa Cc: Maynard Johnson Cc: Naveen N. Rao Cc: Ravi Bangoria Cc: Sukadev Bhattiprolu Link: http://lkml.kernel.org/r/66e848a7bdf2d43b39210a705ff6d828a0865661.153= 0724939.git.sandipan@linux.ibm.com Signed-off-by: Arnaldo Carvalho de Melo Signed-off-by: Sasha Levin --- tools/perf/arch/powerpc/util/skip-callchain-idx.c | 8 ++++++-- 1 file changed, 6 insertions(+), 2 deletions(-) diff --git a/tools/perf/arch/powerpc/util/skip-callchain-idx.c b/tools/perf= /arch/powerpc/util/skip-callchain-idx.c index ef5d59a5742e..699b73be7d91 100644 --- a/tools/perf/arch/powerpc/util/skip-callchain-idx.c +++ b/tools/perf/arch/powerpc/util/skip-callchain-idx.c @@ -58,9 +58,13 @@ static int check_return_reg(int ra_regno, Dwarf_Frame *f= rame) } =20 /* - * Check if return address is on the stack. + * Check if return address is on the stack. If return address + * is in a register (typically R0), it is yet to be saved on + * the stack. */ - if (nops !=3D 0 || ops !=3D NULL) + if ((nops !=3D 0 || ops !=3D NULL) && + !(nops =3D=3D 1 && ops[0].atom =3D=3D DW_OP_regx && + ops[0].number2 =3D=3D 0 && ops[0].offset =3D=3D 0)) return 0; =20 /* --=20 2.17.1