Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1759497Ab2FALaJ (ORCPT ); Fri, 1 Jun 2012 07:30:09 -0400 Received: from e06smtp18.uk.ibm.com ([195.75.94.114]:53898 "EHLO e06smtp18.uk.ibm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1759468Ab2FALaH (ORCPT ); Fri, 1 Jun 2012 07:30:07 -0400 Date: Fri, 1 Jun 2012 13:29:55 +0200 From: Heiko Carstens To: Tejun Heo , Jens Axboe Cc: linux-kernel@vger.kernel.org Subject: WARNING: at block/blk-cgroup.c:867 Message-ID: <20120601112954.GC3535@osiris.boeblingen.de.ibm.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline User-Agent: Mutt/1.5.21 (2010-09-15) x-cbid: 12060111-6892-0000-0000-00000201E683 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2315 Lines: 52 Hi Tejun, for !CONFIG_CFQ_GROUP_IOSCHED the following warning triggered on s390: ------------[ cut here ]------------ WARNING: at block/blk-cgroup.c:867 Modules linked in: Modules linked in: CPU: 3 Not tainted 3.4.0-09547-gfb21aff #1 Process swapper/0 (pid: 1, task: 000000003ff80000, ksp: 000000003ff7f8b8) Krnl PSW : 0704100180000000 00000000003d76ca (blkcg_policy_register+0xca/0xe0) R:0 T:1 IO:1 EX:1 Key:0 M:1 W:0 P:0 AS:0 CC:1 PM:0 EA:3 Krnl GPRS: 0000000000000000 00000000014b85ec 00000000014b85b0 0000000000000000 000000000096fb60 0000000000000000 00000000009a8e78 0000000000000048 000000000099c070 0000000000b6f000 0000000000000000 000000000099c0b8 00000000014b85b0 0000000000667580 000000003ff7fd98 000000003ff7fd70 Krnl Code: 00000000003d76be: a7280001 lhi %r2,1 00000000003d76c2: a7f4ffdf brc 15,3d7680 #00000000003d76c6: a7f40001 brc 15,3d76c8 >00000000003d76ca: a7c8ffea lhi %r12,-22 00000000003d76ce: a7f4ffce brc 15,3d766a 00000000003d76d2: a7f40001 brc 15,3d76d4 00000000003d76d6: a7c80000 lhi %r12,0 00000000003d76da: a7f4ffc2 brc 15,3d765e Call Trace: ([<0000000000b6f000>] initcall_debug+0x0/0x4) [<0000000000989e8a>] cfq_init+0x62/0xd4 [<00000000001000ba>] do_one_initcall+0x3a/0x170 [<000000000096fb60>] kernel_init+0x214/0x2bc [<0000000000623202>] kernel_thread_starter+0x6/0xc [<00000000006231fc>] kernel_thread_starter+0x0/0xc no locks held by swapper/0/1. Last Breaking-Event-Address: [<00000000003d76c6>] blkcg_policy_register+0xc6/0xe0 ---[ end trace b8ef4903fcbf9dd3 ]--- for !CONFIG_CFQ_GROUP_IOSCHED the blkcg_policy_cfq that cfq_init() tries to register with blkcg_policy_register() is in the bss section and therefore initialized with 0. So the warning in blkcg_policy_register() if (WARN_ON(pol->pd_size < sizeof(struct blkg_policy_data))) return -EINVAL; will trigger since pd_size == 0. -- 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/