Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756539Ab2JEO5Z (ORCPT ); Fri, 5 Oct 2012 10:57:25 -0400 Received: from moutng.kundenserver.de ([212.227.17.8]:51322 "EHLO moutng.kundenserver.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756381Ab2JEO4N (ORCPT ); Fri, 5 Oct 2012 10:56:13 -0400 From: Arnd Bergmann To: linux-arm-kernel@lists.infradead.org Cc: linux-kernel@vger.kernel.org, arm@kernel.org, Arnd Bergmann , Tejun Heo , Li Zefan , Ben Blum Subject: [PATCH 07/16] cgroup: fix warning when building without any subsys Date: Fri, 5 Oct 2012 16:55:21 +0200 Message-Id: <1349448930-23976-8-git-send-email-arnd@arndb.de> X-Mailer: git-send-email 1.7.10 In-Reply-To: <1349448930-23976-1-git-send-email-arnd@arndb.de> References: <1349448930-23976-1-git-send-email-arnd@arndb.de> X-Provags-ID: V02:K0:LE5XuEYuxrwkJLoRKhGJEQRYTOsl099eovMV8WrcDl/ FHv6vqGM707U3J7JNo/XoRUKO58d75UtmW6rAMQDN/LodvRRTq kpBZYhPK2nQ0WQ4vb0c0Tw0G8oQ36S/C8k7FzucW7URB1GwR+B 8kjLiZ+FMen0JSLRtSU90ZVtRJWpr4wCCyvPHUKFHeqVKvivqA e2dn0y4pngBlMdGhWSJy3o5dJ2SA12W1muzfx3r1lJqmSJxtvA Ovux/4ohZ2tm1fGtufRKLV9W9wQ9z68LSzs/OFd/Ur2r0uSkPN DiSx0b/b8kqMlsiyMrK5q525tLEmwHHBTTKAd6IvI2rlblLNzE nryaVaNKeSYcL65s6MtTmZP3aNjgM6ns8PlB67O38OkqvIhibQ PQlkS1WC8rGxAUNiZR3AJaGg5DQyc/aH6E= Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1588 Lines: 48 In a configuration where the base cgroup support is enabled but every single cgroup subsys is turned off, CGROUP_BUILTIN_SUBSYS_COUNT is zero, which causes the sanity check code in cgroup_load_subsys to trigger: BUG_ON(ss->subsys_id >= CGROUP_BUILTIN_SUBSYS_COUNT); BUG_ON(subsys[ss->subsys_id] != ss); Gcc first confirms that subsys_id cannot be 0 or larger and consequently warns in the second line. kernel/cgroup.c: In function 'cgroup_load_subsys': kernel/cgroup.c:4326:38: warning: array subscript is below array bounds [-Warray-bounds] Since the subsys_id can never be less than zero, we can just change the type to an unsigned int, which makes the warning go away. Found by building ARM cns3420vb_defconfig. Signed-off-by: Arnd Bergmann Cc: Tejun Heo Cc: Li Zefan Cc: Ben Blum --- include/linux/cgroup.h | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/include/linux/cgroup.h b/include/linux/cgroup.h index c90eaa8..26b99df 100644 --- a/include/linux/cgroup.h +++ b/include/linux/cgroup.h @@ -475,7 +475,7 @@ struct cgroup_subsys { void (*post_clone)(struct cgroup *cgrp); void (*bind)(struct cgroup *root); - int subsys_id; + unsigned int subsys_id; int active; int disabled; int early_init; -- 1.7.10 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/