From mboxrd@z Thu Jan 1 00:00:00 1970 Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753833AbeAJTij (ORCPT + 1 other); Wed, 10 Jan 2018 14:38:39 -0500 Received: from mail-it0-f47.google.com ([209.85.214.47]:39679 "EHLO mail-it0-f47.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753687AbeAJTih (ORCPT ); Wed, 10 Jan 2018 14:38:37 -0500 X-Google-Smtp-Source: ACJfBoum/SmGYCYou2ANPtMIP9sz4LYBGul6mlWJukKp2Wi9MJYDmL42NMPXSyaIHMUjRoxLgPQ4LRtwnh+3G/ieyxw= MIME-Version: 1.0 In-Reply-To: <20180110112815.mgciyf5acwacphkq@pd.tnic> References: <20180110003139.10531-1-andi@firstfloor.org> <1515568506.22302.72.camel@infradead.org> <1515578735.22302.91.camel@infradead.org> <20180110112815.mgciyf5acwacphkq@pd.tnic> From: Linus Torvalds Date: Wed, 10 Jan 2018 11:38:36 -0800 X-Google-Sender-Auth: YHF-Q11JI1eCByQZsly-rAU-KdU Message-ID: Subject: Re: [PATCH] x86/alternatives: Fix optimize_nops() checking To: Borislav Petkov Cc: David Woodhouse , Andi Kleen , Thomas Gleixner , "the arch/x86 maintainers" , Linux Kernel Mailing List , Paul Turner , Andrew Lutomirski , Peter Zijlstra , Tom Lendacky , Tim Chen , Greg Kroah-Hartman , Dave Hansen , Jiri Kosina , Andi Kleen Content-Type: text/plain; charset="UTF-8" Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Return-Path: On Wed, Jan 10, 2018 at 3:28 AM, Borislav Petkov wrote: > > Make sure we scan all bytes before we decide to optimize the NOPs in > there. Can we also add compile-time checking (presumably in objtool, but who knows) that there are no relocations in the alternative section? Because that was the other "oops, this really doesn't work with altinstructions" issue, wasn't it? Linus