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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 8843AC28B2B for ; Fri, 19 Aug 2022 16:40:16 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1350400AbiHSQkO (ORCPT ); Fri, 19 Aug 2022 12:40:14 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:32956 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1353368AbiHSQjZ (ORCPT ); Fri, 19 Aug 2022 12:39:25 -0400 Received: from dfw.source.kernel.org (dfw.source.kernel.org [IPv6:2604:1380:4641:c500::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 98BC49109E; Fri, 19 Aug 2022 09:08:18 -0700 (PDT) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id 27050614DA; Fri, 19 Aug 2022 16:07:30 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 2DDC2C433C1; Fri, 19 Aug 2022 16:07:29 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1660925249; bh=fw9i8RhpOoj2gMS4VBjk+TrGpw1xeKcJG7ORRDyhstA=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=pKTZCeqYKL9PCZRiGqLG/i9SVut/pBxuoDQY19pfr1X4u6lAkwJiXGjv8E1XgUkAl e1glqmszu/fzqCiaAlXDRUernvl1Mjwm8Ml0hRbCxc5e4xT83C4lgxIPTScRDKFRwc zoKA5s8jyT5KDj6coD5cGAd9Y1rnJQSqtRlxlmIc= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Siddh Raman Pant , Ingo Molnar , Sasha Levin Subject: [PATCH 5.10 431/545] x86/numa: Use cpumask_available instead of hardcoded NULL check Date: Fri, 19 Aug 2022 17:43:21 +0200 Message-Id: <20220819153848.703712858@linuxfoundation.org> X-Mailer: git-send-email 2.37.2 In-Reply-To: <20220819153829.135562864@linuxfoundation.org> References: <20220819153829.135562864@linuxfoundation.org> User-Agent: quilt/0.67 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Siddh Raman Pant [ Upstream commit 625395c4a0f4775e0fe00f616888d2e6c1ba49db ] GCC-12 started triggering a new warning: arch/x86/mm/numa.c: In function ‘cpumask_of_node’: arch/x86/mm/numa.c:916:39: warning: the comparison will always evaluate as ‘false’ for the address of ‘node_to_cpumask_map’ will never be NULL [-Waddress] 916 | if (node_to_cpumask_map[node] == NULL) { | ^~ node_to_cpumask_map is of type cpumask_var_t[]. When CONFIG_CPUMASK_OFFSTACK is set, cpumask_var_t is typedef'd to a pointer for dynamic allocation, else to an array of one element. The "wicked game" can be checked on line 700 of include/linux/cpumask.h. The original code in debug_cpumask_set_cpu() and cpumask_of_node() were probably written by the original authors with CONFIG_CPUMASK_OFFSTACK=y (i.e. dynamic allocation) in mind, checking if the cpumask was available via a direct NULL check. When CONFIG_CPUMASK_OFFSTACK is not set, GCC gives the above warning while compiling the kernel. Fix that by using cpumask_available(), which does the NULL check when CONFIG_CPUMASK_OFFSTACK is set, otherwise returns true. Use it wherever such checks are made. Conditional definitions of cpumask_available() can be found along with the definition of cpumask_var_t. Check the cpumask.h reference mentioned above. Fixes: c032ef60d1aa ("cpumask: convert node_to_cpumask_map[] to cpumask_var_t") Fixes: de2d9445f162 ("x86: Unify node_to_cpumask_map handling between 32 and 64bit") Signed-off-by: Siddh Raman Pant Signed-off-by: Ingo Molnar Link: https://lore.kernel.org/r/20220731160913.632092-1-code@siddh.me Signed-off-by: Sasha Levin --- arch/x86/mm/numa.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/arch/x86/mm/numa.c b/arch/x86/mm/numa.c index e94da744386f..9dc31996c7ed 100644 --- a/arch/x86/mm/numa.c +++ b/arch/x86/mm/numa.c @@ -861,7 +861,7 @@ void debug_cpumask_set_cpu(int cpu, int node, bool enable) return; } mask = node_to_cpumask_map[node]; - if (!mask) { + if (!cpumask_available(mask)) { pr_err("node_to_cpumask_map[%i] NULL\n", node); dump_stack(); return; @@ -907,7 +907,7 @@ const struct cpumask *cpumask_of_node(int node) dump_stack(); return cpu_none_mask; } - if (node_to_cpumask_map[node] == NULL) { + if (!cpumask_available(node_to_cpumask_map[node])) { printk(KERN_WARNING "cpumask_of_node(%d): no node_to_cpumask_map!\n", node); -- 2.35.1