From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756161AbcARSPY (ORCPT ); Mon, 18 Jan 2016 13:15:24 -0500 Received: from mx2.suse.de ([195.135.220.15]:49567 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755526AbcARSPV (ORCPT ); Mon, 18 Jan 2016 13:15:21 -0500 Date: Mon, 18 Jan 2016 19:14:57 +0100 From: Borislav Petkov To: Brian Gerst Cc: the arch/x86 maintainers , Linux Kernel Mailing List , Ingo Molnar , "H. Peter Anvin" , Denys Vlasenko , Andy Lutomirski , Linus Torvalds Subject: Re: [PATCH] x86: static_cpu_has_safe: discard dynamic check after init Message-ID: <20160118181457.GG12651@pd.tnic> References: <1452972124-7380-1-git-send-email-brgerst@gmail.com> <20160116193658.GC32085@pd.tnic> <20160117103337.GC8549@pd.tnic> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: User-Agent: Mutt/1.5.24 (2015-08-30) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon, Jan 18, 2016 at 11:52:34AM -0500, Brian Gerst wrote: > It is due to page alignment padding. It was not enough to lose a > whole page from .text in your case. So nothing more got freed. > The size command includes any section that is marked executable in the > text count, including init text. If you use readelf -S vmlinux.o > instead you will notice that .text is the same size or smaller, and > .static_cpu_has (which is freed after boot) is the difference. So we're talking about less than a page here? [19] .static_cpu_has PROGBITS ffffffff81d335d3 011335d3 00000000000002df 0000000000000000 AX 0 0 1 That's 479 bytes. Meh, it doesn't look like it is worth the trouble. Maybe I should build an allyesconfig. -- Regards/Gruss, Boris. SUSE Linux GmbH, GF: Felix Imendörffer, Jane Smithard, Graham Norton, HRB 21284 (AG Nürnberg) --