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=-0.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by aws-us-west-2-korg-lkml-1.web.codeaurora.org (Postfix) with ESMTP id 32429C433EF for ; Fri, 15 Jun 2018 13:14:23 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id D9563208B2 for ; Fri, 15 Jun 2018 13:14:22 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org D9563208B2 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=linux.intel.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 S965654AbeFONOU (ORCPT ); Fri, 15 Jun 2018 09:14:20 -0400 Received: from mga14.intel.com ([192.55.52.115]:10375 "EHLO mga14.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S936209AbeFONOT (ORCPT ); Fri, 15 Jun 2018 09:14:19 -0400 X-Amp-Result: UNKNOWN X-Amp-Original-Verdict: FILE UNKNOWN X-Amp-File-Uploaded: False Received: from fmsmga004.fm.intel.com ([10.253.24.48]) by fmsmga103.fm.intel.com with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384; 15 Jun 2018 06:14:19 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.51,227,1526367600"; d="scan'208";a="63487848" Received: from black.fi.intel.com ([10.237.72.28]) by fmsmga004.fm.intel.com with ESMTP; 15 Jun 2018 06:14:16 -0700 Received: by black.fi.intel.com (Postfix, from userid 1000) id 30ED3172; Fri, 15 Jun 2018 16:14:17 +0300 (EEST) Date: Fri, 15 Jun 2018 16:14:17 +0300 From: "Kirill A. Shutemov" To: Dave Hansen Cc: Ingo Molnar , x86@kernel.org, Thomas Gleixner , "H. Peter Anvin" , Tom Lendacky , Kai Huang , Jacob Pan , linux-kernel@vger.kernel.org, linux-mm@kvack.org Subject: Re: [PATCHv3 08/17] x86/mm: Implement vma_is_encrypted() and vma_keyid() Message-ID: <20180615131416.sl7ib6kt2mg5ufya@black.fi.intel.com> References: <20180612143915.68065-1-kirill.shutemov@linux.intel.com> <20180612143915.68065-9-kirill.shutemov@linux.intel.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: NeoMutt/20170714-126-deb55f (1.8.3) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, Jun 13, 2018 at 06:18:05PM +0000, Dave Hansen wrote: > On 06/12/2018 07:39 AM, Kirill A. Shutemov wrote: > > +bool vma_is_encrypted(struct vm_area_struct *vma) > > +{ > > + return pgprot_val(vma->vm_page_prot) & mktme_keyid_mask; > > +} > > + > > +int vma_keyid(struct vm_area_struct *vma) > > +{ > > + pgprotval_t prot; > > + > > + if (!vma_is_anonymous(vma)) > > + return 0; > > + > > + prot = pgprot_val(vma->vm_page_prot); > > + return (prot & mktme_keyid_mask) >> mktme_keyid_shift; > > +} > > Why do we have a vma_is_anonymous() in one of these but not the other? It shouldn't be there. It's from earlier approach to the function. I'll fix this. And I'll drop vma_is_encrypted(). It is not very useful. > While this reuse of ->vm_page_prot is cute, is there any downside? It's > the first place I know of that we can't derive ->vm_page_prot from > ->vm_flags on non-VM_IO/PFNMAP VMAs. Is that a problem? I don't think so. It need to be covered in pte_modify() and such, but it's about it. That's relatively isolated change and we can move KeyID into a standalone field, if this approach proves to be problematic. -- Kirill A. Shutemov