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=-2.6 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,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 19795C10DCE for ; Wed, 18 Mar 2020 11:32:22 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id E15A42076D for ; Wed, 18 Mar 2020 11:32:21 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1584531141; bh=DCwLDa9CMREm98nGSUNIFZACfzg/R0N7QTZ9y32qucw=; h=Date:From:To:Cc:Subject:References:In-Reply-To:List-ID:From; b=X4k6oeURBSGmBhkFxKmYFz2AHKkf6zU8Se3yMEdYDyGVtk8aM+aNOT4Qxfn8p1h0u FJkCySwAoL1WeCsjG0h+OrfUyh+IxAjAUeb1rr173VOcAbk0Cm6LoyxgqfOuoKBHlw sp3JbtwI/Otq4GoJAACqN2rrO/UrDjDYMsEsovK8= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727850AbgCRLcU (ORCPT ); Wed, 18 Mar 2020 07:32:20 -0400 Received: from foss.arm.com ([217.140.110.172]:48692 "EHLO foss.arm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726933AbgCRLcT (ORCPT ); Wed, 18 Mar 2020 07:32:19 -0400 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 4DC101FB; Wed, 18 Mar 2020 04:32:19 -0700 (PDT) Received: from localhost (unknown [10.37.6.21]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id C2D853F534; Wed, 18 Mar 2020 04:32:18 -0700 (PDT) Date: Wed, 18 Mar 2020 11:32:17 +0000 From: Mark Brown To: Will Deacon Cc: Mark Rutland , Hongbo Yao , linux-kernel@vger.kernel.org, catalin.marinas@arm.com, linux-arm-kernel@lists.infradead.org Subject: Re: [RFC PATCH] arm64: fix the missing ktpi= cmdline check in arm64_kernel_unmapped_at_el0() Message-ID: <20200318113217.GA4553@sirena.org.uk> 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> MIME-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha512; protocol="application/pgp-signature"; boundary="a8Wt8u1KmwUX3Y2C" Content-Disposition: inline In-Reply-To: <20200317210154.GA19752@willie-the-truck> X-Cookie: Oh no, not again. User-Agent: Mutt/1.10.1 (2018-07-13) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org --a8Wt8u1KmwUX3Y2C Content-Type: text/plain; charset=us-ascii Content-Disposition: inline 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. --a8Wt8u1KmwUX3Y2C Content-Type: application/pgp-signature; name="signature.asc" -----BEGIN PGP SIGNATURE----- iQEzBAABCgAdFiEEreZoqmdXGLWf4p/qJNaLcl1Uh9AFAl5yBrwACgkQJNaLcl1U h9AbqAf/evqpddBA32ry7tRUmR0UzfLjJnQcOzDZJA22veN9vfzgRpCHNAbcKIwd Fe0Su8ymJM2h26R94qkUOhy0ZZR3hyVx/4N8DPtKYQMGkj9iixI4zxNbk3DMKyng e+6+4+zC2+O+ee2+R7zU081sM9Fw1oAovKckQZ+MQsfF79MUm9d3SaWvI7yIGPau VkPkKHpc2Lz355RKv1bxi4hsJ6fIR3ktHCNY3VjZxdVLkjf01OcFmWruzEcoQgRo bRZloTMy+lFes2YRJTZMoGElW4rPcC8pJm/b7qLWQJz8L5i3w291N/h6eqd5yGfb +X5Pa0pOsZPnZ+ec+gNO8IQLywTehQ== =Aee1 -----END PGP SIGNATURE----- --a8Wt8u1KmwUX3Y2C--