From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-wr0-f197.google.com (mail-wr0-f197.google.com [209.85.128.197]) by kanga.kvack.org (Postfix) with ESMTP id 2FA7E6B0005 for ; Mon, 29 Jan 2018 10:39:49 -0500 (EST) Received: by mail-wr0-f197.google.com with SMTP id 17so5932555wrm.10 for ; Mon, 29 Jan 2018 07:39:49 -0800 (PST) Received: from mail-sor-f41.google.com (mail-sor-f41.google.com. [209.85.220.41]) by mx.google.com with SMTPS id t23sor5441973edb.49.2018.01.29.07.39.47 for (Google Transport Security); Mon, 29 Jan 2018 07:39:47 -0800 (PST) Date: Mon, 29 Jan 2018 18:39:45 +0300 From: "Kirill A. Shutemov" Subject: Re: [PATCHv7 5/4] x86/boot/compressed/64: Support switching from 5- to 4-level paging Message-ID: <20180129153945.sme6f2zx3fpj24qy@node.shutemov.name> References: <20180129115351.85224-1-kirill.shutemov@linux.intel.com> <20180129150758.81016-1-kirill.shutemov@linux.intel.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20180129150758.81016-1-kirill.shutemov@linux.intel.com> Sender: owner-linux-mm@kvack.org List-ID: To: "Kirill A. Shutemov" Cc: Ingo Molnar , x86@kernel.org, Thomas Gleixner , "H. Peter Anvin" , Linus Torvalds , Andy Lutomirski , Cyrill Gorcunov , Borislav Petkov , Andi Kleen , Matthew Wilcox , linux-mm@kvack.org, linux-kernel@vger.kernel.org On Mon, Jan 29, 2018 at 06:07:58PM +0300, Kirill A. Shutemov wrote: > + /* > + * We are in 5-level paging mode, but we want to switch to 4-level. > + * Let's take the first entry in the top-level page table as our new CR3. > + */ > + movl %cr3, %eax > + movl (%eax), %eax > + movl %eax, %cr3 Aghh.. Please ignore this. It would fail if CR3 points above 4G. -- 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