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=-2.1 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 83A6AC2BC61 for ; Tue, 30 Oct 2018 15:29:49 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 365B120657 for ; Tue, 30 Oct 2018 15:29:49 +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="d0/wpFci" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 365B120657 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=infradead.org Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727673AbeJaAXm (ORCPT ); Tue, 30 Oct 2018 20:23:42 -0400 Received: from bombadil.infradead.org ([198.137.202.133]:53160 "EHLO bombadil.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727648AbeJaAXm (ORCPT ); Tue, 30 Oct 2018 20:23:42 -0400 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=oulFfH9JYVCCDp8mixdnJfogwwFY+N/JvVZ5AUVW1Cs=; b=d0/wpFciFWl09/DEtystyKyfZ Ayf549jf7VMrRZVYfWJx5MBeivHLVTe08BdBuTXu+xE0C4OFakZm3V88PbSGYrOg7orsvl3/YkrLI 5RoRKQrbVidA6JSw44P7MRdDzW20hJItCajSNaT+muQxSHrHkQ0Le44cxrP/W6/aaIL4zpOoW1YDu pztgkEZXx5Od8vWVKJbZK1I0ay9kq9u2V9B4yWNVJ1TF0p1LReeg/hVlZOcJ31Cq/jfiUha7tfHsY +Sn+z714xYPPiUvWJ5thKByh0wCUq5nnEp0lMtjqkjhkhJ9WWyvjmgjbk2RuYVDQnr84syN1XJHie 0Paq/9f7Q==; Received: from [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 1gHPTo-0007D0-0a; Tue, 30 Oct 2018 08:35:10 +0000 Received: by hirez.programming.kicks-ass.net (Postfix, from userid 1000) id B36DC202A40A3; Tue, 30 Oct 2018 09:32:10 +0100 (CET) Date: Tue, 30 Oct 2018 09:32:10 +0100 From: Peter Zijlstra To: Zhenzhong Duan Cc: Linux-Kernel , mingo@redhat.com, luto@kernel.org, konrad.wilk@oracle.com, dwmw@amazon.co.uk, tglx@linutronix.de, Srinivas REDDY Eeda , bp@suse.de, daniel@iogearbox.net, yamada.masahiro@socionext.com, michal.lkml@markovi.net, hpa@zytor.com Subject: Re: [PATCH 1/3] retpolines: Only enable retpoline when compiler support it Message-ID: <20181030083210.GA1459@hirez.programming.kicks-ass.net> References: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: 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, Oct 29, 2018 at 11:55:04PM -0700, Zhenzhong Duan wrote: > Since retpoline capable compilers are widely available, make > CONFIG_RETPOLINE hard depend on it. > > Change KBUILD to use CONFIG_RETPOLINE_SUPPORT to avoid conflict with > CONFIG_RETPOLINE which is used by kernel. > > With all that stuff, the check of RETPOLINE is changed to > CONFIG_RETPOLINE. So what happens when we select CONFIG_RETPOLINE but do not have RETPOLINE_SUPPORT ? From a quick reading we'll silently build a !retpoline kernel. I would expect a build failure.