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=-4.1 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,UNPARSEABLE_RELAY autolearn=no 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 A7C7AC433E1 for ; Wed, 22 Jul 2020 18:51:43 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 7E7A220717 for ; Wed, 22 Jul 2020 18:51:43 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=oracle.com header.i=@oracle.com header.b="kfhvgLnn" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726642AbgGVSvn (ORCPT ); Wed, 22 Jul 2020 14:51:43 -0400 Received: from userp2120.oracle.com ([156.151.31.85]:46024 "EHLO userp2120.oracle.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726390AbgGVSvm (ORCPT ); Wed, 22 Jul 2020 14:51:42 -0400 Received: from pps.filterd (userp2120.oracle.com [127.0.0.1]) by userp2120.oracle.com (8.16.0.42/8.16.0.42) with SMTP id 06MIhL3E130198; Wed, 22 Jul 2020 18:50:53 GMT DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=oracle.com; h=date : from : to : cc : subject : message-id : references : mime-version : content-type : in-reply-to; s=corp-2020-01-29; bh=C/y7nOWN2zZL8t7wViPxEtK7Dpw4bYa251sNZduPTUI=; b=kfhvgLnnRnVduoCN7BiAlRJeiFcydBpsKpk3H3LvTTQL0V/Xjuc7F+MYz8Qtg9FvrR72 01AuL4uqCujMX9h0uNuhfLP/vi0mIybit3wj1/dWwtuMC/Qn41ZnHwpq8Ii5kpmSVxrP vHy7wwTEUuoUAW+qup38aSeAJEn1ClbMjgYJ8nyDn8/2G39amkB6DTV65TywLTyishla LLz6eO3M2yrtis/aybW5mKqYNw9W7uypLsb6M3W1d1k8e05I4cUCXzdHoxXRgd/tf5eF 8UJPzzpztOJU5rOe7Xvuy9dLSd0oSqoTj4s4ZLaOxs1TRcbMMBdu7MJtJo8OdjhbvnX8 Uw== Received: from aserp3020.oracle.com (aserp3020.oracle.com [141.146.126.70]) by userp2120.oracle.com with ESMTP id 32d6kssbxh-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=FAIL); Wed, 22 Jul 2020 18:50:53 +0000 Received: from pps.filterd (aserp3020.oracle.com [127.0.0.1]) by aserp3020.oracle.com (8.16.0.42/8.16.0.42) with SMTP id 06MIi6nW167531; Wed, 22 Jul 2020 18:50:53 GMT Received: from aserv0121.oracle.com (aserv0121.oracle.com [141.146.126.235]) by aserp3020.oracle.com with ESMTP id 32eq20erpy-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Wed, 22 Jul 2020 18:50:52 +0000 Received: from abhmp0011.oracle.com (abhmp0011.oracle.com [141.146.116.17]) by aserv0121.oracle.com (8.14.4/8.13.8) with ESMTP id 06MIopgc012980; Wed, 22 Jul 2020 18:50:51 GMT Received: from localhost (/10.175.216.251) by default (Oracle Beehive Gateway v4.0) with ESMTP ; Wed, 22 Jul 2020 11:50:51 -0700 Date: Wed, 22 Jul 2020 20:50:47 +0200 From: Gregory Herrero To: Catalin Marinas Cc: Steven Rostedt , linux-kernel@vger.kernel.org, stable@vger.kernel.org, Will Deacon , linux-arm-kernel@lists.infradead.org Subject: Re: [PATCH] recordmcount: only record relocation of type R_AARCH64_CALL26 on arm64. Message-ID: <20200722185047.GW17377@ltoracle> References: <20200717143338.19302-1-gregory.herrero@oracle.com> <20200717133003.025f2096@oasis.local.home> <20200722163650.GI27540@gaia> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20200722163650.GI27540@gaia> X-Proofpoint-Virus-Version: vendor=nai engine=6000 definitions=9690 signatures=668680 X-Proofpoint-Spam-Details: rule=notspam policy=default score=0 suspectscore=1 spamscore=0 malwarescore=0 mlxscore=0 phishscore=0 bulkscore=0 adultscore=0 mlxlogscore=999 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-2006250000 definitions=main-2007220119 X-Proofpoint-Virus-Version: vendor=nai engine=6000 definitions=9690 signatures=668680 X-Proofpoint-Spam-Details: rule=notspam policy=default score=0 malwarescore=0 suspectscore=1 bulkscore=0 mlxscore=0 mlxlogscore=999 impostorscore=0 priorityscore=1501 lowpriorityscore=0 phishscore=0 spamscore=0 adultscore=0 clxscore=1015 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-2006250000 definitions=main-2007220119 Sender: stable-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org On Wed, Jul 22, 2020 at 05:36:50PM +0100, Catalin Marinas wrote: > On Fri, Jul 17, 2020 at 01:30:03PM -0400, Steven Rostedt wrote: > > On Fri, 17 Jul 2020 16:33:38 +0200 > > gregory.herrero@oracle.com wrote: > > > From: Gregory Herrero > > > Currently, if a section has a relocation to '_mcount' symbol, a new > > > __mcount_loc entry will be added whatever the relocation type is. > > > This is problematic when a relocation to '_mcount' is in the middle of a > > > section and is not a call for ftrace use. > > > > > > Such relocation could be generated with below code for example: > > > bool is_mcount(unsigned long addr) > > > { > > > return (target == (unsigned long) &_mcount); > > > } > > > > > > With this snippet of code, ftrace will try to patch the mcount location > > > generated by this code on module load and fail with: > > > > > > Call trace: > > > ftrace_bug+0xa0/0x28c > > > ftrace_process_locs+0x2f4/0x430 > > > ftrace_module_init+0x30/0x38 > > > load_module+0x14f0/0x1e78 > > > __do_sys_finit_module+0x100/0x11c > > > __arm64_sys_finit_module+0x28/0x34 > > > el0_svc_common+0x88/0x194 > > > el0_svc_handler+0x38/0x8c > > > el0_svc+0x8/0xc > > > ---[ end trace d828d06b36ad9d59 ]--- > > > ftrace failed to modify > > > [] 0xffffa2dbf3a3a41c > > > actual: 66:a9:3c:90 > > > Initializing ftrace call sites > > > ftrace record flags: 2000000 > > > (0) > > > expected tramp: ffffa2dc6cf66724 > > > > > > So Limit the relocation type to R_AARCH64_CALL26 as in perl version of > > > recordmcount. > > > > I'd rather have this go through the arm64 tree, as they can test it > > better than I can. > > > > Acked-by: Steven Rostedt (VMware) > > Thanks Steve. > > > > Fixes: ed60453fa8f8 ("ARM: 6511/1: ftrace: add ARM support for C version of recordmcount") > > This Fixes tag looks wrong. The above commit was for arm32. > Thanks for catching this. It should be as below instead: Fixes: af64d2aa872a ("ftrace: Add arm64 support to recordmcount") Should I send a V2? Thanks, Greg