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=-1.0 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED 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 0C73FC28CC3 for ; Fri, 7 Jun 2019 09:33:58 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id D0203208E3 for ; Fri, 7 Jun 2019 09:33:57 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727904AbfFGJd5 (ORCPT ); Fri, 7 Jun 2019 05:33:57 -0400 Received: from foss.arm.com ([217.140.110.172]:36516 "EHLO foss.arm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727233AbfFGJd4 (ORCPT ); Fri, 7 Jun 2019 05:33:56 -0400 X-Greylist: delayed 516 seconds by postgrey-1.27 at vger.kernel.org; Fri, 07 Jun 2019 05:33:56 EDT Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id AF56828; Fri, 7 Jun 2019 02:25:19 -0700 (PDT) Received: from [10.1.196.105] (eglon.cambridge.arm.com [10.1.196.105]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 53B153F96A; Fri, 7 Jun 2019 02:25:18 -0700 (PDT) Subject: Re: [PATCH v3 1/8] arm64: Do not enable IRQs for ct_user_exit To: Julien Thierry Cc: linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, rostedt@goodmis.org, marc.zyngier@arm.com, yuzenghui@huawei.com, wanghaibin.wang@huawei.com, will.deacon@arm.com, catalin.marinas@arm.com, mark.rutland@arm.com, liwei391@huawei.com References: <1559813517-41540-1-git-send-email-julien.thierry@arm.com> <1559813517-41540-2-git-send-email-julien.thierry@arm.com> From: James Morse Message-ID: <96a0eb12-bbf2-0854-a5e7-25246327e3ec@arm.com> Date: Fri, 7 Jun 2019 10:25:16 +0100 User-Agent: Mozilla/5.0 (X11; Linux aarch64; rv:60.0) Gecko/20100101 Thunderbird/60.7.0 MIME-Version: 1.0 In-Reply-To: <1559813517-41540-2-git-send-email-julien.thierry@arm.com> Content-Type: text/plain; charset=utf-8 Content-Language: en-GB Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi Julien, On 06/06/2019 10:31, Julien Thierry wrote: > For el0_dbg and el0_error, DAIF bits get explicitly cleared before > calling ct_user_exit. > > When context tracking is disabled, DAIF gets set (almost) immediately > after. When context tracking is enabled, among the first things done > is disabling IRQs. > > What is actually needed is: > - PSR.D = 0 so the system can be debugged (should be already the case) > - PSR.A = 0 so async error can be handled during context tracking > > Do not clear PSR.I in those two locations. (last time I looked at this I wrongly assumed ct_user_exit() should be run with interrupts masked, but that isn't what you're saying). Reviewed-by: James Morse Thanks, James