From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-wr0-f198.google.com (mail-wr0-f198.google.com [209.85.128.198]) by kanga.kvack.org (Postfix) with ESMTP id 179C66B0033 for ; Mon, 4 Dec 2017 09:57:59 -0500 (EST) Received: by mail-wr0-f198.google.com with SMTP id f4so10438524wre.9 for ; Mon, 04 Dec 2017 06:57:59 -0800 (PST) Received: from mail-sor-f65.google.com (mail-sor-f65.google.com. [209.85.220.65]) by mx.google.com with SMTPS id a9sor7055843edn.5.2017.12.04.06.57.57 for (Google Transport Security); Mon, 04 Dec 2017 06:57:57 -0800 (PST) Date: Mon, 4 Dec 2017 17:57:55 +0300 From: "Kirill A. Shutemov" Subject: Re: [PATCH] x86/mm: Rewrite sme_populate_pgd() in a more sensible way Message-ID: <20171204145755.6xu2w6a6og56rq5v@node.shutemov.name> References: <20171204112323.47019-1-kirill.shutemov@linux.intel.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: Sender: owner-linux-mm@kvack.org List-ID: To: Tom Lendacky Cc: "Kirill A. Shutemov" , Thomas Gleixner , Ingo Molnar , "H. Peter Anvin" , x86@kernel.org, Borislav Petkov , Brijesh Singh , linux-mm@kvack.org, linux-kernel@vger.kernel.org On Mon, Dec 04, 2017 at 08:19:11AM -0600, Tom Lendacky wrote: > On 12/4/2017 5:23 AM, Kirill A. Shutemov wrote: > > sme_populate_pgd() open-codes a lot of things that are not needed to be > > open-coded. > > > > Let's rewrite it in a more stream-lined way. > > > > This would also buy us boot-time switching between support between > > paging modes, when rest of the pieces will be upstream. > > Hi Kirill, > > Unfortunately, some of these can't be changed. The use of p4d_offset(), > pud_offset(), etc., use non-identity mapped virtual addresses which cause > failures at this point of the boot process. Wat? Virtual address is virtual address. p?d_offset() doesn't care about what mapping you're using. > Also, calls such as __p4d(), __pud(), etc., are part of the paravirt > support and can't be used yet, either. Yeah, I missed this. native_make_p?d() has to be used instead. > I can take a closer look at some of the others (p*d_none() and > p*d_large()) which make use of the native_ macros, but my worry would be > that these get changed in the future to the non-native calls and then > boot failures occur. If you want to avoid paravirt altogher for whole compilation unit, one more option would be to put #undef CONFIG_PARAVIRT before all includes. That's hack, but it works. We already use this in arch/x86/boot/compressed code. -- Kirill A. Shutemov -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: email@kvack.org