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=-9.1 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_PASS, URIBL_BLOCKED,USER_AGENT_GIT autolearn=unavailable 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 63D69C43381 for ; Wed, 27 Mar 2019 19:10:41 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 2D019206BA for ; Wed, 27 Mar 2019 19:10:41 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1553713841; bh=F6LVIjqoBQw4+4vg1nhHNG/PqzrDUarrDFl95pWBNEc=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=2f6W3L4BKaUdEOsRqorhic7lET0dElP/DLgncKbOcZk0eZZten5lCYe3Avr+YisHL bznNGsPqoSe6VPTMbDvRzVZfaNA5G5PzRGkV0ISAsuLOma3bkgqJUZ38SnAiFi1RSB 9P2RZcsIZDbbylVtTjDwH5U3lNEtabSfOBOocihI= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2389214AbfC0TKj (ORCPT ); Wed, 27 Mar 2019 15:10:39 -0400 Received: from mail.kernel.org ([198.145.29.99]:53172 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2388948AbfC0SK6 (ORCPT ); Wed, 27 Mar 2019 14:10:58 -0400 Received: from sasha-vm.mshome.net (c-73-47-72-35.hsd1.nh.comcast.net [73.47.72.35]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 087682184D; Wed, 27 Mar 2019 18:10:56 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1553710257; bh=F6LVIjqoBQw4+4vg1nhHNG/PqzrDUarrDFl95pWBNEc=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=Ko7SEPAlJilWBOWBBmuUPHTmYEnJ8EoqFZN289Qk/NfCE/Ooxq9nrIjNpRXKXSY5A shQ1HVo5hv/1F5bpLgOQBIRL/l9352lRavJVBr7+h7RD5IYWKRqAdfE7uIMTl/hhAU GFKYgp5g/zzqa8o3B7dVbxIsO+VwM5ikzic6bAAM= From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Qian Cai , Dave Hansen , Andrew Morton , Linus Torvalds , Sasha Levin , linux-mm@kvack.org Subject: [PATCH AUTOSEL 4.19 021/192] mm/sparse: fix a bad comparison Date: Wed, 27 Mar 2019 14:07:33 -0400 Message-Id: <20190327181025.13507-21-sashal@kernel.org> X-Mailer: git-send-email 2.19.1 In-Reply-To: <20190327181025.13507-1-sashal@kernel.org> References: <20190327181025.13507-1-sashal@kernel.org> MIME-Version: 1.0 X-Patchwork-Hint: Ignore Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Qian Cai [ Upstream commit d778015ac95bc036af73342c878ab19250e01fe1 ] next_present_section_nr() could only return an unsigned number -1, so just check it specifically where compilers will convert -1 to unsigned if needed. mm/sparse.c: In function 'sparse_init_nid': mm/sparse.c:200:20: warning: comparison of unsigned expression >= 0 is always true [-Wtype-limits] ((section_nr >= 0) && \ ^~ mm/sparse.c:478:2: note: in expansion of macro 'for_each_present_section_nr' for_each_present_section_nr(pnum_begin, pnum) { ^~~~~~~~~~~~~~~~~~~~~~~~~~~ mm/sparse.c:200:20: warning: comparison of unsigned expression >= 0 is always true [-Wtype-limits] ((section_nr >= 0) && \ ^~ mm/sparse.c:497:2: note: in expansion of macro 'for_each_present_section_nr' for_each_present_section_nr(pnum_begin, pnum) { ^~~~~~~~~~~~~~~~~~~~~~~~~~~ mm/sparse.c: In function 'sparse_init': mm/sparse.c:200:20: warning: comparison of unsigned expression >= 0 is always true [-Wtype-limits] ((section_nr >= 0) && \ ^~ mm/sparse.c:520:2: note: in expansion of macro 'for_each_present_section_nr' for_each_present_section_nr(pnum_begin + 1, pnum_end) { ^~~~~~~~~~~~~~~~~~~~~~~~~~~ Link: http://lkml.kernel.org/r/20190228181839.86504-1-cai@lca.pw Fixes: c4e1be9ec113 ("mm, sparsemem: break out of loops early") Signed-off-by: Qian Cai Reviewed-by: Andrew Morton Cc: Dave Hansen Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds Signed-off-by: Sasha Levin --- mm/sparse.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/mm/sparse.c b/mm/sparse.c index 10b07eea9a6e..45950a074bdb 100644 --- a/mm/sparse.c +++ b/mm/sparse.c @@ -196,7 +196,7 @@ static inline int next_present_section_nr(int section_nr) } #define for_each_present_section_nr(start, section_nr) \ for (section_nr = next_present_section_nr(start-1); \ - ((section_nr >= 0) && \ + ((section_nr != -1) && \ (section_nr <= __highest_present_section_nr)); \ section_nr = next_present_section_nr(section_nr)) -- 2.19.1