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=unavailable 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 A4089C282CF for ; Mon, 28 Jan 2019 15:42:50 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 70E8D20880 for ; Mon, 28 Jan 2019 15:42:50 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726877AbfA1Pmt (ORCPT ); Mon, 28 Jan 2019 10:42:49 -0500 Received: from usa-sjc-mx-foss1.foss.arm.com ([217.140.101.70]:47322 "EHLO foss.arm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726792AbfA1Pmr (ORCPT ); Mon, 28 Jan 2019 10:42:47 -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 C7FCC80D; Mon, 28 Jan 2019 07:42:46 -0800 (PST) Received: from [10.1.197.45] (e112298-lin.cambridge.arm.com [10.1.197.45]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 8957D3F589; Mon, 28 Jan 2019 07:42:44 -0800 (PST) Subject: Re: [PATCH v9 01/26] arm64: Fix HCR.TGE status for NMI contexts To: James Morse , linux-arm-kernel@lists.infradead.org Cc: linux-kernel@vger.kernel.org, daniel.thompson@linaro.org, joel@joelfernandes.org, marc.zyngier@arm.com, christoffer.dall@arm.com, catalin.marinas@arm.com, will.deacon@arm.com, mark.rutland@arm.com, Arnd Bergmann , linux-arch@vger.kernel.org, stable@vger.kernel.org References: <1548084825-8803-1-git-send-email-julien.thierry@arm.com> <1548084825-8803-2-git-send-email-julien.thierry@arm.com> <8e8c4f5b-5b83-7bbc-1b84-36d68e210968@arm.com> From: Julien Thierry Message-ID: <847c54ef-ea41-eea5-8aff-72e0cea465f8@arm.com> Date: Mon, 28 Jan 2019 15:42:42 +0000 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:60.0) Gecko/20100101 Thunderbird/60.2.1 MIME-Version: 1.0 In-Reply-To: <8e8c4f5b-5b83-7bbc-1b84-36d68e210968@arm.com> Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi James, On 28/01/2019 11:48, James Morse wrote: > Hi Julien, > > On 21/01/2019 15:33, Julien Thierry wrote: >> When using VHE, the host needs to clear HCR_EL2.TGE bit in order >> to interract with guest TLBs, switching from EL2&0 translation regime > > (interact) > > >> to EL1&0. >> >> However, some non-maskable asynchronous event could happen while TGE is >> cleared like SDEI. Because of this address translation operations >> relying on EL2&0 translation regime could fail (tlb invalidation, >> userspace access, ...). >> >> Fix this by properly setting HCR_EL2.TGE when entering NMI context and >> clear it if necessary when returning to the interrupted context. > > Yes please. This would not have been fun to debug! > > Reviewed-by: James Morse > > Thanks. > > I was looking for why we need core code to do this, instead of updating the > arch's call sites. Your 'irqdesc: Add domain handlers for NMIs' patch (pointed > to from the cover letter) is the reason: core-code calls nmi_enter()/nmi_exit() > itself. > Yes, that's the main reason. > >> diff --git a/arch/arm64/include/asm/hardirq.h b/arch/arm64/include/asm/hardirq.h >> index 1473fc2..94b7481 100644 >> --- a/arch/arm64/include/asm/hardirq.h >> +++ b/arch/arm64/include/asm/hardirq.h >> @@ -19,6 +19,7 @@ >> #include >> #include >> #include >> +#include > > percpu.h? > sysreg.h? > barrier.h? > Good point, I'll add those. Thanks, -- Julien Thierry