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=-2.3 required=3.0 tests=DKIM_INVALID,DKIM_SIGNED, 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 34BC5C43387 for ; Mon, 17 Dec 2018 19:29:51 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id EF2F1214D8 for ; Mon, 17 Dec 2018 19:29:50 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (2048-bit key) header.d=infradead.org header.i=@infradead.org header.b="DG+asg4W" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2388258AbeLQT3t (ORCPT ); Mon, 17 Dec 2018 14:29:49 -0500 Received: from bombadil.infradead.org ([198.137.202.133]:49692 "EHLO bombadil.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727326AbeLQT3t (ORCPT ); Mon, 17 Dec 2018 14:29:49 -0500 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=bombadil.20170209; h=In-Reply-To:Content-Type:MIME-Version :References:Message-ID:Subject:Cc:To:From:Date:Sender:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Id: List-Help:List-Unsubscribe:List-Subscribe:List-Post:List-Owner:List-Archive; bh=BXXNNLVW5grKt4FOJrloD/uc3vKk282SFf0cGSGpw/g=; b=DG+asg4W0sdLRgY4VUmvVRmz8 jBu/11d7zvchtxKvZeJ2Tnl1NVgJCSHoqz9pHD+5qGPqM1GN5/PNBBc76pvGvr1kyrvPplW3j1MqS SXEAEROSA/TpnzlEfVUMkRobfuiNZHZuWngf8O2O4Jz3v9B2VHgQIG6Q5BQfrEKgGDnER/vfYS1g4 JJjkl1xgnV3Y789f2yAqJ3tC6JRBeoxSWg7Rwup4TjZWwpdsFlLjB336JgWOZ+ghCZGGECtfHvyZ2 8KYIFun+9Q6Tb6ZcHPBUnVCX4fcLTXRM97RSLBteZ2mNexpO/RmYStQxNs2T+Gj88XZgmsh2pmCof omc28M/EQ==; Received: from j217100.upc-j.chello.nl ([24.132.217.100] helo=hirez.programming.kicks-ass.net) by bombadil.infradead.org with esmtpsa (Exim 4.90_1 #2 (Red Hat Linux)) id 1gYyaD-0002CP-21; Mon, 17 Dec 2018 19:29:41 +0000 Received: by hirez.programming.kicks-ass.net (Postfix, from userid 1000) id 5957C2027DA91; Mon, 17 Dec 2018 20:29:38 +0100 (CET) Date: Mon, 17 Dec 2018 20:29:38 +0100 From: Peter Zijlstra To: Josh Poimboeuf Cc: Andi Kleen , 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: <20181217192938.GF2218@hirez.programming.kicks-ass.net> References: <20181217173900.ygifx7khwmzn2gv2@treble> <20181217180434.GS25620@tassilo.jf.intel.com> <20181217181638.dfexg6mkmbfyzfli@treble> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20181217181638.dfexg6mkmbfyzfli@treble> 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 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. When/if we get the LTO trainwreck sorted -- which very much includes getting that memory-order-consume fixed -- we can revisit all that.