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=-3.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED autolearn=no 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 37C12C433E0 for ; Thu, 4 Jun 2020 07:58:24 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 20F362075B for ; Thu, 4 Jun 2020 07:58:24 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726846AbgFDH6V (ORCPT ); Thu, 4 Jun 2020 03:58:21 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:49232 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726047AbgFDH6T (ORCPT ); Thu, 4 Jun 2020 03:58:19 -0400 Received: from Galois.linutronix.de (Galois.linutronix.de [IPv6:2a0a:51c0:0:12e:550::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 208C7C05BD1E; Thu, 4 Jun 2020 00:58:19 -0700 (PDT) Received: from p5de0bf0b.dip0.t-ipconnect.de ([93.224.191.11] helo=nanos.tec.linutronix.de) by Galois.linutronix.de with esmtpsa (TLS1.2:DHE_RSA_AES_256_CBC_SHA256:256) (Exim 4.80) (envelope-from ) id 1jgklM-0007rw-IR; Thu, 04 Jun 2020 09:58:08 +0200 Received: by nanos.tec.linutronix.de (Postfix, from userid 1000) id CB26BFFBE0; Thu, 4 Jun 2020 09:58:07 +0200 (CEST) From: Thomas Gleixner To: Kees Cook , linux-kernel@vger.kernel.org Cc: Kees Cook , Linus Torvalds , Miguel Ojeda , Alexander Potapenko , Joe Perches , Andy Whitcroft , x86@kernel.org, drbd-dev@lists.linbit.com, linux-block@vger.kernel.org, b43-dev@lists.infradead.org, netdev@vger.kernel.org, linux-wireless@vger.kernel.org, linux-ide@vger.kernel.org, linux-clk@vger.kernel.org, linux-spi@vger.kernel.org, linux-mm@kvack.org, clang-built-linux@googlegroups.com Subject: Re: [PATCH 01/10] x86/mm/numa: Remove uninitialized_var() usage In-Reply-To: <20200603233203.1695403-2-keescook@chromium.org> Date: Thu, 04 Jun 2020 09:58:07 +0200 Message-ID: <874krr8dps.fsf@nanos.tec.linutronix.de> MIME-Version: 1.0 Content-Type: text/plain X-Linutronix-Spam-Score: -1.0 X-Linutronix-Spam-Level: - X-Linutronix-Spam-Status: No , -1.0 points, 5.0 required, ALL_TRUSTED=-1,SHORTCIRCUIT=-0.0001 Sender: netdev-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org Kees Cook writes: > -#ifdef NODE_NOT_IN_PAGE_FLAGS > - pfn_align = node_map_pfn_alignment(); > - if (pfn_align && pfn_align < PAGES_PER_SECTION) { > - printk(KERN_WARNING "Node alignment %LuMB < min %LuMB, rejecting NUMA config\n", > - PFN_PHYS(pfn_align) >> 20, > - PFN_PHYS(PAGES_PER_SECTION) >> 20); > - return -EINVAL; > + if (IS_ENABLED(NODE_NOT_IN_PAGE_FLAGS)) { Hrm, clever ... > + unsigned long pfn_align = node_map_pfn_alignment(); > + > + if (pfn_align && pfn_align < PAGES_PER_SECTION) { > + pr_warn("Node alignment %LuMB < min %LuMB, rejecting NUMA config\n", > + PFN_PHYS(pfn_align) >> 20, > + PFN_PHYS(PAGES_PER_SECTION) >> 20); > + return -EINVAL; > + } > } > -#endif > if (!numa_meminfo_cover_memory(mi)) > return -EINVAL; > > diff --git a/include/linux/page-flags-layout.h b/include/linux/page-flags-layout.h > index 71283739ffd2..1a4cdec2bd29 100644 > --- a/include/linux/page-flags-layout.h > +++ b/include/linux/page-flags-layout.h > @@ -100,7 +100,7 @@ > * there. This includes the case where there is no node, so it is implicit. > */ > #if !(NODES_WIDTH > 0 || NODES_SHIFT == 0) > -#define NODE_NOT_IN_PAGE_FLAGS > +#define NODE_NOT_IN_PAGE_FLAGS 1 but if we ever lose the 1 then the above will silently compile the code within the IS_ENABLED() section out. Thanks, tglx