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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id E1B3FCCA479 for ; Mon, 20 Jun 2022 15:27:50 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S243658AbiFTP1t (ORCPT ); Mon, 20 Jun 2022 11:27:49 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:57972 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S240728AbiFTP1h (ORCPT ); Mon, 20 Jun 2022 11:27:37 -0400 Received: from mga09.intel.com (mga09.intel.com [134.134.136.24]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 1BFB7CF for ; Mon, 20 Jun 2022 08:27:37 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1655738857; x=1687274857; h=message-id:date:mime-version:subject:to:cc:references: from:in-reply-to:content-transfer-encoding; bh=8giL0qZv3yIElRFo4fVuIKMG5Tx+3XAwog7jJ8DWOI8=; b=HGkMJcnYqjyHGcfkEv9R5gWI7r/GfJbsj335jnSYq/mkbOYAkmQM2dCk 3vvCql/v97NP8gOKVfVQTb0QQlme9PrT5cqogQ1ihUHpp6QwywejCbPF1 l43OIZm+ja0RXfq9UAse40B7N9Zrt5qh7sNtIfHKmGfitQqGcW/hbsXmt nChCpq1pO+p6PNxdeQHPn0N8eulkIspqJHOZj21DouHK4VmMVomYQoX+P /bResCgQwRNdFk2odYv1DpuxmCGgUqHGKi/eIWTAjvhLsmUXEoVkqDCmn UwTKGL3BNAnSl3I0wg4rmQfJ5qxuTmXGYNZmdaigeyQv1zAMue583PoAO g==; X-IronPort-AV: E=McAfee;i="6400,9594,10384"; a="280654134" X-IronPort-AV: E=Sophos;i="5.92,207,1650956400"; d="scan'208";a="280654134" Received: from orsmga006.jf.intel.com ([10.7.209.51]) by orsmga102.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 20 Jun 2022 08:27:36 -0700 X-IronPort-AV: E=Sophos;i="5.92,207,1650956400"; d="scan'208";a="561998169" Received: from echeresh-mobl1.amr.corp.intel.com (HELO [10.209.15.145]) ([10.209.15.145]) by orsmga006-auth.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 20 Jun 2022 08:27:36 -0700 Message-ID: <63ccccac-2aa7-8850-9cd3-a8b7b89e1872@intel.com> Date: Mon, 20 Jun 2022 08:27:33 -0700 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:91.0) Gecko/20100101 Thunderbird/91.9.1 Subject: Re: [PATCH 1/2] x86/pat: fix x86_has_pat_wp() Content-Language: en-US To: Juergen Gross , Borislav Petkov Cc: xen-devel@lists.xenproject.org, x86@kernel.org, linux-kernel@vger.kernel.org, jbeulich@suse.com, Dave Hansen , Andy Lutomirski , Peter Zijlstra , Thomas Gleixner , Ingo Molnar , "H. Peter Anvin" References: <20220503132207.17234-1-jgross@suse.com> <20220503132207.17234-2-jgross@suse.com> <1cfde4bf-241f-d94c-ffd7-2a11cf9aa1f2@suse.com> From: Dave Hansen In-Reply-To: <1cfde4bf-241f-d94c-ffd7-2a11cf9aa1f2@suse.com> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 6/20/22 03:41, Juergen Gross wrote: >> But I'm only guessing - this needs a *lot* more elaboration and >> explanation why exactly this is needed. > > I will correct the code and update the commit message. It would also be great to cover the end-user-visible impact of the bug and the fix. It _looks_ like it will probably only affect an SEV system's ability to read some EFI data. That will presumably be pretty bad because it ends up reading from an encrypted mapping instead of a decrypted one. The pr_warn("failed to early memremap... is (counterintuitively) what is wanted here. Right?