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 29159C433EF for ; Tue, 1 Feb 2022 19:34:54 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229808AbiBATew (ORCPT ); Tue, 1 Feb 2022 14:34:52 -0500 Received: from dfw.source.kernel.org ([139.178.84.217]:42022 "EHLO dfw.source.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229568AbiBATew (ORCPT ); Tue, 1 Feb 2022 14:34:52 -0500 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 3420C61617 for ; Tue, 1 Feb 2022 19:34:52 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 63804C340EC; Tue, 1 Feb 2022 19:34:50 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linux-foundation.org; s=korg; t=1643744091; bh=SYrTVBhR7xhSEV1kwAWJUGtNJ/YJ+xz0hhhjYaX/io8=; h=Date:To:From:Subject:From; b=V4iHbpFXlgD3TCA2Ct1AegHt8Fefujjl/w4zxE7/cwwQrhugqsDU0Kw+mmfH9IRrs DF4PR3mGmNJIdFGhRBVwph5KawzNYcylYIaQrAlL/JwGK3JITwkNTKdfDF6U0dAPqQ QgJeb2Kh77PdRz+hBRqaDw5by5lifGQmtlJY6mYg= Received: by hp1 (sSMTP sendmail emulation); Tue, 01 Feb 2022 11:34:49 -0800 Date: Tue, 01 Feb 2022 11:34:49 -0800 To: mm-commits@vger.kernel.org, mingo@kernel.org, kirill.shutemov@linux.intel.com, jforbes@redhat.com, aquini@redhat.com, longman@redhat.com, akpm@linux-foundation.org From: Andrew Morton Subject: + mm-sparsemem-fix-mem_section-will-never-be-null-gcc-12-warning.patch added to -mm tree Message-Id: <20220201193450.63804C340EC@smtp.kernel.org> Precedence: bulk Reply-To: linux-kernel@vger.kernel.org List-ID: X-Mailing-List: mm-commits@vger.kernel.org The patch titled Subject: mm/sparsemem: fix 'mem_section' will never be NULL gcc 12 warning has been added to the -mm tree. Its filename is mm-sparsemem-fix-mem_section-will-never-be-null-gcc-12-warning.patch This patch should soon appear at https://ozlabs.org/~akpm/mmots/broken-out/mm-sparsemem-fix-mem_section-will-never-be-null-gcc-12-warning.patch and later at https://ozlabs.org/~akpm/mmotm/broken-out/mm-sparsemem-fix-mem_section-will-never-be-null-gcc-12-warning.patch Before you just go and hit "reply", please: a) Consider who else should be cc'ed b) Prefer to cc a suitable mailing list as well c) Ideally: find the original patch on the mailing list and do a reply-to-all to that, adding suitable additional cc's *** Remember to use Documentation/process/submit-checklist.rst when testing your code *** The -mm tree is included into linux-next and is updated there every 3-4 working days ------------------------------------------------------ From: Waiman Long Subject: mm/sparsemem: fix 'mem_section' will never be NULL gcc 12 warning The gcc 12 compiler reports a warning on the following code: static inline struct mem_section *__nr_to_section(unsigned long nr) { #ifdef CONFIG_SPARSEMEM_EXTREME if (!mem_section) return NULL; #endif : With CONFIG_SPARSEMEM_EXTREME on, the mem_section definition is extern struct mem_section **mem_section; Obviously, mem_section cannot be NULL, but *mem_section can be if memory hasn't been allocated for the dynamic mem_section[] array yet. Fix this warning by checking for "!*mem_section" instead. Link: https://lkml.kernel.org/r/20220201192924.672675-1-longman@redhat.com Fixes: 83e3c48729d9 ("mm/sparsemem: Allocate mem_section at runtime for CONFIG_SPARSEMEM_EXTREME=y") Signed-off-by: Waiman Long Cc: Kirill A. Shutemov Cc: Ingo Molnar Cc: Justin Forbes Cc: Rafael Aquini Signed-off-by: Andrew Morton --- include/linux/mmzone.h | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) --- a/include/linux/mmzone.h~mm-sparsemem-fix-mem_section-will-never-be-null-gcc-12-warning +++ a/include/linux/mmzone.h @@ -1390,7 +1390,7 @@ static inline unsigned long *section_to_ static inline struct mem_section *__nr_to_section(unsigned long nr) { #ifdef CONFIG_SPARSEMEM_EXTREME - if (!mem_section) + if (!*mem_section) return NULL; #endif if (!mem_section[SECTION_NR_TO_ROOT(nr)]) _ Patches currently in -mm which might be from longman@redhat.com are mm-sparsemem-fix-mem_section-will-never-be-null-gcc-12-warning.patch ipc-mqueue-use-get_tree_nodev-in-mqueue_get_tree.patch