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=-2.3 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_1 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 C4121C4332B for ; Thu, 19 Mar 2020 06:15:05 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id A1C9820714 for ; Thu, 19 Mar 2020 06:15:05 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727039AbgCSGPE (ORCPT ); Thu, 19 Mar 2020 02:15:04 -0400 Received: from szxga05-in.huawei.com ([45.249.212.191]:11719 "EHLO huawei.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1725787AbgCSGPE (ORCPT ); Thu, 19 Mar 2020 02:15:04 -0400 Received: from DGGEMS411-HUB.china.huawei.com (unknown [172.30.72.60]) by Forcepoint Email with ESMTP id C1409E9F6CAAF9054A0E; Thu, 19 Mar 2020 14:15:00 +0800 (CST) Received: from [127.0.0.1] (10.173.221.207) by DGGEMS411-HUB.china.huawei.com (10.3.19.211) with Microsoft SMTP Server id 14.3.487.0; Thu, 19 Mar 2020 14:14:56 +0800 Subject: Re: [RFC PATCH] arm64: fix the missing ktpi= cmdline check in arm64_kernel_unmapped_at_el0() To: Will Deacon , Mark Brown CC: Mark Rutland , , , References: <20200317114708.109283-1-yaohongbo@huawei.com> <20200317121050.GH8831@lakrids.cambridge.arm.com> <20200317124323.GA16200@willie-the-truck> <20200317135719.GH3971@sirena.org.uk> <20200317151813.GA16579@willie-the-truck> <20200317163638.GI3971@sirena.org.uk> <20200317210154.GA19752@willie-the-truck> <20200318113217.GA4553@sirena.org.uk> <20200318201259.GA7463@willie-the-truck> From: Hongbo Yao Message-ID: Date: Thu, 19 Mar 2020 14:14:55 +0800 User-Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:68.0) Gecko/20100101 Thunderbird/68.3.0 MIME-Version: 1.0 In-Reply-To: <20200318201259.GA7463@willie-the-truck> Content-Type: text/plain; charset="utf-8" Content-Language: en-US Content-Transfer-Encoding: 7bit X-Originating-IP: [10.173.221.207] X-CFilter-Loop: Reflected Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 2020/3/19 4:13, Will Deacon wrote: > On Wed, Mar 18, 2020 at 11:32:17AM +0000, Mark Brown wrote: >> On Tue, Mar 17, 2020 at 09:01:54PM +0000, Will Deacon wrote: >>> On Tue, Mar 17, 2020 at 04:36:38PM +0000, Mark Brown wrote: >> >>>> I'd need to go back and retest to confirm but it looks like always had >>>> the issue that we'd install some nG mappings early even with KPTI >>>> disabled on the command line so your change is just restoring the >>>> previous behaviour and we're no worse than we were before. >> >>> Urgh, this code brings back really bad memories :( :( :( >> >> Tell me about it. >> >>> So I've hacked the following, which appears to work but damn I'd like >>> somebody else to look at this. I also have a nagging feeling that you >>> implemented it like this at some point, but we tried to consolidate things >>> during review. >> >>> Thoughts? >> >> I don't think I did *exactly* this but it's familiar yeah. It looks >> sensible and I can't think of any problems but that doesn't mean there >> aren't any. > > Well, thanks for having a look! > > Hongbo -- please can you confirm that this fixes the problem that you are > seeing? Hi, Will, Sorry for the late response. This fixes the problem for me. Tested-by: Hongbo Yao Thanks, Hongbo. > Will > > . >