From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753766AbbIZTzk (ORCPT ); Sat, 26 Sep 2015 15:55:40 -0400 Received: from mail-wi0-f177.google.com ([209.85.212.177]:34114 "EHLO mail-wi0-f177.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753415AbbIZTzi (ORCPT ); Sat, 26 Sep 2015 15:55:38 -0400 Date: Sat, 26 Sep 2015 20:55:35 +0100 From: Matt Fleming To: "H. Peter Anvin" Cc: Andy Lutomirski , Ingo Molnar , Thomas Gleixner , Matt Fleming , "linux-kernel@vger.kernel.org" , "linux-efi@vger.kernel.org" , "Lee, Chun-Yi" , Borislav Petkov , Leif Lindholm , Peter Jones , James Bottomley , Matthew Garrett , Dave Young , stable , Ard Biesheuvel , Linus Torvalds , Borislav Petkov , Andy Lutomirski , Denys Vlasenko , Brian Gerst , Andrew Morton Subject: Re: [PATCH 1/2] x86/efi: Map EFI memmap entries in-order at runtime Message-ID: <20150926195535.GB3144@codeblueprint.co.uk> References: <1443218539-7610-1-git-send-email-matt@codeblueprint.co.uk> <1443218539-7610-2-git-send-email-matt@codeblueprint.co.uk> <20150926055643.GA25877@gmail.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.5.21 (2010-09-15) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Sat, 26 Sep, at 10:20:22AM, H. Peter Anvin wrote: > > I think it "works" because the affected BIOSes don't put spaces > between the chunks. I have discussed this with Matt. Right, that's very true. Though note that the current mapping algorithm will handle a gap <= PMD_SIZE, it's just anything larger than PMD_SIZE we "squash" to the next multiple of PMD_SIZE. It's unclear whether the firmware toolchains would even support references between sections with a PMD_SIZE gap between them, and I think the firmware engineers would have to go out of their way to actually insert such a gap. -- Matt Fleming, Intel Open Source Technology Center From mboxrd@z Thu Jan 1 00:00:00 1970 From: Matt Fleming Subject: Re: [PATCH 1/2] x86/efi: Map EFI memmap entries in-order at runtime Date: Sat, 26 Sep 2015 20:55:35 +0100 Message-ID: <20150926195535.GB3144@codeblueprint.co.uk> References: <1443218539-7610-1-git-send-email-matt@codeblueprint.co.uk> <1443218539-7610-2-git-send-email-matt@codeblueprint.co.uk> <20150926055643.GA25877@gmail.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: Content-Disposition: inline In-Reply-To: Sender: linux-efi-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org To: "H. Peter Anvin" Cc: Andy Lutomirski , Ingo Molnar , Thomas Gleixner , Matt Fleming , "linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org" , "linux-efi-u79uwXL29TY76Z2rM5mHXA@public.gmane.org" , "Lee, Chun-Yi" , Borislav Petkov , Leif Lindholm , Peter Jones , James Bottomley , Matthew Garrett , Dave Young , stable , Ard Biesheuvel , Linus Torvalds , Borislav Petkov , Andy Lutomirski , Denys Vlasenko , Brian Gerst , Andrew Morton List-Id: linux-efi@vger.kernel.org On Sat, 26 Sep, at 10:20:22AM, H. Peter Anvin wrote: > > I think it "works" because the affected BIOSes don't put spaces > between the chunks. I have discussed this with Matt. Right, that's very true. Though note that the current mapping algorithm will handle a gap <= PMD_SIZE, it's just anything larger than PMD_SIZE we "squash" to the next multiple of PMD_SIZE. It's unclear whether the firmware toolchains would even support references between sections with a PMD_SIZE gap between them, and I think the firmware engineers would have to go out of their way to actually insert such a gap. -- Matt Fleming, Intel Open Source Technology Center