From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-2.5 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_PASS,USER_AGENT_MUTT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 4CC64C43387 for ; Mon, 17 Dec 2018 20:55:38 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 2550320874 for ; Mon, 17 Dec 2018 20:55:38 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2388511AbeLQUzh (ORCPT ); Mon, 17 Dec 2018 15:55:37 -0500 Received: from mga17.intel.com ([192.55.52.151]:6935 "EHLO mga17.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727157AbeLQUzg (ORCPT ); Mon, 17 Dec 2018 15:55:36 -0500 X-Amp-Result: UNKNOWN X-Amp-Original-Verdict: FILE UNKNOWN X-Amp-File-Uploaded: False Received: from orsmga006.jf.intel.com ([10.7.209.51]) by fmsmga107.fm.intel.com with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384; 17 Dec 2018 12:55:36 -0800 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.56,366,1539673200"; d="scan'208";a="101404045" Received: from tassilo.jf.intel.com (HELO tassilo.localdomain) ([10.7.201.137]) by orsmga006.jf.intel.com with ESMTP; 17 Dec 2018 12:55:35 -0800 Received: by tassilo.localdomain (Postfix, from userid 1000) id D82AF300B49; Mon, 17 Dec 2018 12:55:35 -0800 (PST) Date: Mon, 17 Dec 2018 12:55:35 -0800 From: Andi Kleen To: Peter Zijlstra Cc: Josh Poimboeuf , Arnd Bergmann , Linux Kernel Mailing List , the arch/x86 maintainers , Steven Rostedt , Miroslav Benes Subject: Re: objtool warnings for kernel/trace/trace_selftest_dynamic.o Message-ID: <20181217205535.GT25620@tassilo.jf.intel.com> References: <20181217173900.ygifx7khwmzn2gv2@treble> <20181217180434.GS25620@tassilo.jf.intel.com> <20181217181638.dfexg6mkmbfyzfli@treble> <20181217192938.GF2218@hirez.programming.kicks-ass.net> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20181217192938.GF2218@hirez.programming.kicks-ass.net> User-Agent: Mutt/1.10.1 (2018-07-13) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon, Dec 17, 2018 at 08:29:38PM +0100, Peter Zijlstra wrote: > On Mon, Dec 17, 2018 at 12:16:38PM -0600, Josh Poimboeuf wrote: > > > > Yes LTO causes the to be treated like static functions. > > > > > > I guess noclone is unlikely to be really needed here because these > > > functions are unlikely to be cloned. > > > > > > So as a workaround it could be removed. > > > > > > But note we have other noclone functions in the tree (like in KVM) > > > which actually need it. > > > > How about we just use the __used attribute then? It seems to have the > > same result of preventing IPA optimizations (without the weird side > > effect of missing frame pointers). > > AFAIK we don't have any in-tree LTO, so it can all go in the bin. I have patches for 4.20, and I was actually thinking about resending soon. It will need a few changes, but not too bad. FWIW there's also a user base who used the out of tree patches for some time. > > When/if we get the LTO trainwreck sorted -- which very much includes > getting that memory-order-consume fixed -- we can revisit all that. What do you mean? I'm not aware of any LTO problems with memory-order-consume? -Andi