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=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 3BA0AECDFB0 for ; Sun, 15 Jul 2018 07:42:19 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id DD4A820882 for ; Sun, 15 Jul 2018 07:42:18 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org DD4A820882 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=linux.vnet.ibm.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 S1726177AbeGOH6C (ORCPT ); Sun, 15 Jul 2018 03:58:02 -0400 Received: from mx0b-001b2d01.pphosted.com ([148.163.158.5]:44104 "EHLO mx0a-001b2d01.pphosted.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1726018AbeGOH6C (ORCPT ); Sun, 15 Jul 2018 03:58:02 -0400 Received: from pps.filterd (m0098416.ppops.net [127.0.0.1]) by mx0b-001b2d01.pphosted.com (8.16.0.22/8.16.0.22) with SMTP id w6F7Txpr115578 for ; Sun, 15 Jul 2018 03:36:03 -0400 Received: from e06smtp03.uk.ibm.com (e06smtp03.uk.ibm.com [195.75.94.99]) by mx0b-001b2d01.pphosted.com with ESMTP id 2k7xdqnpek-1 (version=TLSv1.2 cipher=AES256-GCM-SHA384 bits=256 verify=NOT) for ; Sun, 15 Jul 2018 03:36:02 -0400 Received: from localhost by e06smtp03.uk.ibm.com with IBM ESMTP SMTP Gateway: Authorized Use Only! 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Violators will be prosecuted; (version=TLSv1/SSLv3 cipher=AES256-GCM-SHA384 bits=256/256) Sun, 15 Jul 2018 08:35:59 +0100 Received: from d06av26.portsmouth.uk.ibm.com (d06av26.portsmouth.uk.ibm.com [9.149.105.62]) by b06cxnps4076.portsmouth.uk.ibm.com (8.14.9/8.14.9/NCO v10.0) with ESMTP id w6F7ZwbU34013276 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=FAIL); Sun, 15 Jul 2018 07:35:58 GMT Received: from d06av26.portsmouth.uk.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id 3F1D5AE053; Sun, 15 Jul 2018 10:36:17 +0100 (BST) Received: from d06av26.portsmouth.uk.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id E274DAE051; Sun, 15 Jul 2018 10:36:15 +0100 (BST) Received: from [9.79.225.171] (unknown [9.79.225.171]) by d06av26.portsmouth.uk.ibm.com (Postfix) with ESMTP; Sun, 15 Jul 2018 10:36:15 +0100 (BST) Subject: Re: [PATCH] livepatch: Remove reliable stacktrace check in klp_try_switch_task() To: Josh Poimboeuf Cc: Miroslav Benes , Jiri Kosina , live-patching@vger.kernel.org, linux-kernel@vger.kernel.org References: <1531382706-9732-1-git-send-email-kamalesh@linux.vnet.ibm.com> <20180713183756.gfddtn3gbwkwpqbj@treble> From: Kamalesh Babulal Date: Sun, 15 Jul 2018 13:05:56 +0530 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:52.0) Gecko/20100101 Thunderbird/52.9.1 MIME-Version: 1.0 In-Reply-To: <20180713183756.gfddtn3gbwkwpqbj@treble> Content-Type: text/plain; charset=utf-8; format=flowed Content-Language: en-US Content-Transfer-Encoding: 7bit X-TM-AS-GCONF: 00 x-cbid: 18071507-0012-0000-0000-0000028A4EB1 X-IBM-AV-DETECTION: SAVI=unused REMOTE=unused XFE=unused x-cbparentid: 18071507-0013-0000-0000-000020BC0240 Message-Id: X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10434:,, definitions=2018-07-15_02:,, signatures=0 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 priorityscore=1501 malwarescore=0 suspectscore=0 phishscore=0 bulkscore=0 spamscore=0 clxscore=1015 lowpriorityscore=0 mlxscore=0 impostorscore=0 mlxlogscore=995 adultscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.0.1-1806210000 definitions=main-1807150092 Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Saturday 14 July 2018 12:07 AM, Josh Poimboeuf wrote: >> We bail out during patch registration for architectures, those don't >> support reliable stack trace. > > Does anybody know if that change was intentional? I thought the plan > was to allow non-consistency-model arches to still use livepatch, and > that they'd just have to 'force' patches to completion instead. That > seems a little more forgiving. > The initial proposal was to allow 'force' feature on architectures without HAVE_RELIABLE_STACKTRACE support and use pr_notice() to warn user about the non-availability of consistency model. It was argued against, as it will encourage people to use it as an alternative instead of adding HAVE_RELIABLE_STACKTRACE support to the kernel. -- cheers, Kamalesh.