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=-4.0 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,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 04A14C04EB9 for ; Wed, 5 Dec 2018 13:02:42 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id BE6232081B for ; Wed, 5 Dec 2018 13:02:41 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org BE6232081B Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=arm.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 S1727267AbeLENCk (ORCPT ); Wed, 5 Dec 2018 08:02:40 -0500 Received: from foss.arm.com ([217.140.101.70]:54050 "EHLO foss.arm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726909AbeLENCk (ORCPT ); Wed, 5 Dec 2018 08:02:40 -0500 Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.72.51.249]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id D0D5FA78; Wed, 5 Dec 2018 05:02:39 -0800 (PST) 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 0525D3F575; Wed, 5 Dec 2018 05:02:37 -0800 (PST) Subject: Re: [PATCH v6 21/24] arm64: Handle serror in NMI context To: Catalin Marinas Cc: Julien Thierry , linux-arm-kernel@lists.infradead.org, Mark Rutland , daniel.thompson@linaro.org, marc.zyngier@arm.com, will.deacon@arm.com, linux-kernel@vger.kernel.org, christoffer.dall@arm.com, joel@joelfernandes.org, Dave Martin References: <1542023835-21446-1-git-send-email-julien.thierry@arm.com> <1542023835-21446-22-git-send-email-julien.thierry@arm.com> <20181204180917.GE19210@arrakis.emea.arm.com> From: James Morse Message-ID: <3ff15164-11db-d3c9-e194-a35facf9971d@arm.com> Date: Wed, 5 Dec 2018 13:02:36 +0000 User-Agent: Mozilla/5.0 (X11; Linux aarch64; rv:60.0) Gecko/20100101 Thunderbird/60.3.0 MIME-Version: 1.0 In-Reply-To: <20181204180917.GE19210@arrakis.emea.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 Catalin, On 04/12/2018 18:09, Catalin Marinas wrote: > On Mon, Nov 12, 2018 at 11:57:12AM +0000, Julien Thierry wrote: >> diff --git a/arch/arm64/kernel/traps.c b/arch/arm64/kernel/traps.c >> index 5f4d9ac..66344cd 100644 >> --- a/arch/arm64/kernel/traps.c >> +++ b/arch/arm64/kernel/traps.c >> @@ -897,13 +897,17 @@ bool arm64_is_fatal_ras_serror(struct pt_regs *regs, unsigned int esr) >> >> asmlinkage void do_serror(struct pt_regs *regs, unsigned int esr) >> { >> - nmi_enter(); >> + const bool was_in_nmi = in_nmi(); >> + >> + if (!was_in_nmi) >> + nmi_enter(); >> >> /* non-RAS errors are not containable */ >> if (!arm64_is_ras_serror(esr) || arm64_is_fatal_ras_serror(regs, esr)) >> arm64_serror_panic(regs, esr); >> >> - nmi_exit(); >> + if (!was_in_nmi) >> + nmi_exit(); >> } > > Do we actually need nmi_enter/exit in the outer do_serror() function? > Could we just move it to arm64_serror_panic()? They might need to be here in the future: if we support kernel-first we would have extra calls in here that need to be in_nmi(), the same if we call out to APEI to support APCI's NOTIFY_SEI. Thanks, James