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=-5.6 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_PASS,USER_AGENT_MUTT 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 D2848C4321A for ; Thu, 25 Apr 2019 16:36:58 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 0773820891 for ; Thu, 25 Apr 2019 16:36:59 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=alien8.de header.i=@alien8.de header.b="kV/m+79j" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728570AbfDYQg5 (ORCPT ); Thu, 25 Apr 2019 12:36:57 -0400 Received: from mail.skyhub.de ([5.9.137.197]:57472 "EHLO mail.skyhub.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725941AbfDYQg5 (ORCPT ); Thu, 25 Apr 2019 12:36:57 -0400 Received: from zn.tnic (p200300EC2F0E43001D86563D61B131D5.dip0.t-ipconnect.de [IPv6:2003:ec:2f0e:4300:1d86:563d:61b1:31d5]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.skyhub.de (SuperMail on ZX Spectrum 128k) with ESMTPSA id DE16A1EC050B; Thu, 25 Apr 2019 18:36:54 +0200 (CEST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=alien8.de; s=dkim; t=1556210215; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:in-reply-to:in-reply-to: references:references; bh=UF9yiYSdp+bqbl4vCjqwOikVi1eCtCz+Zg7/2WDARJw=; b=kV/m+79jALQI1SIUHyZS/iVqIPFCNzfSqxYTx3FPj4F0x4oPEWWLq1yatQ1q0R9G9CI1gJ tWVAYj0QEqtPb3+EvsUr2mlR6ftcBWLTsIr9n9qBg8kWKvyMHtUV40eIKB4wJw2NTVkaZF 2dIrXfbNbKnxIPdylPQVnVI8Fj9YuaM= Date: Thu, 25 Apr 2019 18:36:50 +0200 From: Borislav Petkov To: Rick Edgecombe Cc: Andy Lutomirski , Ingo Molnar , linux-kernel@vger.kernel.org, x86@kernel.org, hpa@zytor.com, Thomas Gleixner , Nadav Amit , Dave Hansen , Peter Zijlstra , linux_dti@icloud.com, linux-integrity@vger.kernel.org, linux-security-module@vger.kernel.org, akpm@linux-foundation.org, kernel-hardening@lists.openwall.com, linux-mm@kvack.org, will.deacon@arm.com, ard.biesheuvel@linaro.org, kristen@linux.intel.com, deneen.t.dock@intel.com, Nadav Amit Subject: Re: [PATCH v4 04/23] x86/mm: Save DRs when loading a temporary mm Message-ID: <20190425163650.GB5199@zn.tnic> References: <20190422185805.1169-1-rick.p.edgecombe@intel.com> <20190422185805.1169-5-rick.p.edgecombe@intel.com> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: <20190422185805.1169-5-rick.p.edgecombe@intel.com> 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 > Subject: Re: [PATCH v4 04/23] x86/mm: Save DRs when loading a temporary mm s/DRs/debug registers/ On Mon, Apr 22, 2019 at 11:57:46AM -0700, Rick Edgecombe wrote: > From: Nadav Amit > > Prevent user watchpoints from mistakenly firing while the temporary mm > is being used. As the addresses that of the temporary mm might overlap s/that // > those of the user-process, this is necessary to prevent wrong signals > or worse things from happening. > > Cc: Andy Lutomirski > Signed-off-by: Nadav Amit > Signed-off-by: Rick Edgecombe > --- > arch/x86/include/asm/mmu_context.h | 23 +++++++++++++++++++++++ > 1 file changed, 23 insertions(+) -- Regards/Gruss, Boris. Good mailing practices for 400: avoid top-posting and trim the reply.