Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755906AbdDJQ4M (ORCPT ); Mon, 10 Apr 2017 12:56:12 -0400 Received: from esa5.hgst.iphmx.com ([216.71.153.144]:39958 "EHLO esa5.hgst.iphmx.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755890AbdDJQ4J (ORCPT ); Mon, 10 Apr 2017 12:56:09 -0400 X-IronPort-AV: E=Sophos;i="5.37,182,1488816000"; d="scan'208";a="9536232" From: Bart Van Assche To: "tj@kernel.org" , "paolo.valente@linaro.org" , "axboe@kernel.dk" CC: "ulf.hansson@linaro.org" , "linux-kernel@vger.kernel.org" , "fchecconi@gmail.com" , "avanzini.arianna@gmail.com" , "linux-block@vger.kernel.org" , "linus.walleij@linaro.org" , "broonie@kernel.org" Subject: Re: [PATCH V2 00/16] Introduce the BFQ I/O scheduler Thread-Topic: [PATCH V2 00/16] Introduce the BFQ I/O scheduler Thread-Index: AQHSqh4G1UE1IuscBUSmOtTDlhXb2aG+4m8A Date: Mon, 10 Apr 2017 16:56:04 +0000 Message-ID: <1491843362.4199.14.camel@sandisk.com> References: <20170331124743.3530-1-paolo.valente@linaro.org> In-Reply-To: <20170331124743.3530-1-paolo.valente@linaro.org> Accept-Language: en-US Content-Language: en-US X-MS-Has-Attach: X-MS-TNEF-Correlator: authentication-results: kernel.org; dkim=none (message not signed) header.d=none;kernel.org; dmarc=none action=none header.from=sandisk.com; x-ms-exchange-messagesentrepresentingtype: 1 x-originating-ip: [63.163.107.100] x-microsoft-exchange-diagnostics: 1;CY1PR0401MB1536;7:uL5MaG3pCUE0Yov701Cypn8or7dW2c5BQfU7iDBXHT70W8dptp80V2n6OcIO3FmVLqDSxObbD/AiDyjimKU/s3RCnQd8y/mEVHQiv6lRgrUHtpVZHX+gKCooKQiCGp9qY7cCLXBuqXrOZ1WSqusXXYgpAioT3/iQN5yyvj3/x6hX3shfbc0Fb9fpjIpTpHcfMThexG3ifaDClGBYjHC+Ic/fgtlkOEbCHZa+V2WXqvCun0m8hGts+XIAQqrLxkCK5G9xs0ainK0VuSUPc3zxQadSW9z8oeA08N+I6ggYPPfW0wCxuAZ13hj8s1JBQxD3rzimDeOk0+wBL9iEMcQ+aQ==;20:jDjFP3MjOi3ODiI6dbsLt+urx0SIaNa1JWBNYlpT5xemKAqFmX9Wh6cdte2U/hWBBF207Adhehulx0sJTTqxltdBBLP5P4h2ZbsBcx1FqHy+X3FmGTCQH/2ui0nEoAv/wSPpb4nlV0CQellQ6lIK0PnQ0xbVtQ6UUvTWtEmdGEc= x-ms-office365-filtering-correlation-id: f7b7661e-0c33-4691-9b0b-08d48032799b x-ms-office365-filtering-ht: Tenant x-microsoft-antispam: UriScan:;BCL:0;PCL:0;RULEID:(22001)(2017030254075)(48565401081)(201703131423075)(201703031133081)(201702281549075);SRVR:CY1PR0401MB1536; wdcipoutbound: EOP-TRUE x-microsoft-antispam-prvs: x-exchange-antispam-report-test: UriScan:(166708455590820); x-exchange-antispam-report-cfa-test: BCL:0;PCL:0;RULEID:(6040450)(601004)(2401047)(8121501046)(5005006)(93006095)(93001095)(10201501046)(3002001)(6055026)(6041248)(201703131423075)(201702281528075)(201703061421075)(20161123564025)(20161123560025)(20161123555025)(20161123562025)(6072148);SRVR:CY1PR0401MB1536;BCL:0;PCL:0;RULEID:;SRVR:CY1PR0401MB1536; x-forefront-prvs: 027367F73D x-forefront-antispam-report: SFV:NSPM;SFS:(10019020)(6009001)(39400400002)(39850400002)(39860400002)(39450400003)(39840400002)(39410400002)(377424004)(51234002)(24454002)(33646002)(189998001)(54356999)(76176999)(50986999)(8936002)(5660300001)(66066001)(3846002)(2900100001)(305945005)(7736002)(3660700001)(122556002)(8676002)(575784001)(2201001)(86362001)(2906002)(3280700002)(106356001)(6506006)(7416002)(99286003)(81166006)(6436002)(77096006)(6512007)(54906002)(53936002)(6306002)(4326008)(25786009)(38730400002)(102836003)(6246003)(6116002)(39060400002)(2501003)(229853002)(36756003)(103116003)(6486002)(2950100002);DIR:OUT;SFP:1102;SCL:1;SRVR:CY1PR0401MB1536;H:CY1PR0401MB1536.namprd04.prod.outlook.com;FPR:;SPF:None;MLV:ovrnspm;PTR:InfoNoRecords;LANG:en; spamdiagnosticoutput: 1:99 spamdiagnosticmetadata: NSPM Content-Type: text/plain; charset="iso-8859-1" Content-ID: <54912FFF03D924428A8D6DBD6D43A8A8@namprd04.prod.outlook.com> MIME-Version: 1.0 X-OriginatorOrg: sandisk.com X-MS-Exchange-CrossTenant-originalarrivaltime: 10 Apr 2017 16:56:04.0856 (UTC) X-MS-Exchange-CrossTenant-fromentityheader: Hosted X-MS-Exchange-CrossTenant-id: b61c8803-16f3-4c35-9b17-6f65f441df86 X-MS-Exchange-Transport-CrossTenantHeadersStamped: CY1PR0401MB1536 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Transfer-Encoding: 8bit X-MIME-Autoconverted: from quoted-printable to 8bit by mail.home.local id v3AGuKYE017250 Content-Length: 3292 Lines: 69 On Fri, 2017-03-31 at 14:47 +0200, Paolo Valente wrote: > [ ... ] Hello Paolo, Is the git tree that is available at https://github.com/Algodev-github/bfq-mq appropriate for testing BFQ? If I merge that tree with v4.11-rc6 and if I run the srp-test software against that tree as follows: ./run_tests -e bfq-mq -t 02-mq then the following appears on the console: [ 2748.650352] BUG: unable to handle kernel NULL pointer dereference at 00000000000000d0 [ 2748.650442] IP: __bfq_insert_request+0x26/0x650 [bfq_mq_iosched] [ 2748.650509] PGD 0? [ 2748.650511]? [ 2748.650585] Oops: 0000 [#1] SMP [ 2748.651107] CPU: 9 PID: 10772 Comm: kworker/9:2H Tainted: G??????????I?????4.11.0-rc6-dbg+ #1 [ 2748.651191] Workqueue: kblockd blk_mq_requeue_work [ 2748.651228] task: ffff88037c808040 task.stack: ffffc90003b4c000 [ 2748.651268] RIP: 0010:__bfq_insert_request+0x26/0x650 [bfq_mq_iosched] [ 2748.651307] RSP: 0018:ffffc90003b4f9d8 EFLAGS: 00010002 [ 2748.651345] RAX: 0000000000000001 RBX: 0000000000000000 RCX: 0000000000000001 [ 2748.651383] RDX: 0000000000000001 RSI: ffff880377f52e80 RDI: ffff880401f774e8 [ 2748.651423] RBP: ffffc90003b4fa80 R08: 9093955f00000000 R09: 0000000000000001 [ 2748.651464] R10: ffffc90003b4fa00 R11: ffffffffa06d0d53 R12: ffff880401f77840 [ 2748.651506] R13: ffff880401f774e8 R14: ffff880378a451e0 R15: 0000000000000000 [ 2748.651547] FS:??0000000000000000(0000) GS:ffff88046f040000(0000) knlGS:0000000000000000 [ 2748.651588] CS:??0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 2748.651626] CR2: 00000000000000d0 CR3: 0000000001c0f000 CR4: 00000000001406e0 [ 2748.651664] Call Trace: [ 2748.651778]??bfq_insert_request+0x83/0x280 [bfq_mq_iosched] [ 2748.651934]??bfq_insert_requests+0x50/0x70 [bfq_mq_iosched] [ 2748.651975]??blk_mq_sched_insert_request+0x11e/0x170 [ 2748.652015]??blk_insert_cloned_request+0xb6/0x1f0 [ 2748.652361]??map_request+0x13c/0x290 [dm_mod] [ 2748.652403]??dm_mq_queue_rq+0x90/0x160 [dm_mod] [ 2748.652441]??blk_mq_dispatch_rq_list+0x1f2/0x3e0 [ 2748.652479]??blk_mq_sched_dispatch_requests+0xf1/0x190 [ 2748.652516]??__blk_mq_run_hw_queue+0x12d/0x1c0 [ 2748.652553]??__blk_mq_delay_run_hw_queue+0xe3/0xf0 [ 2748.652593]??blk_mq_run_hw_queues+0x5c/0x80 [ 2748.652632]??blk_mq_requeue_work+0x132/0x150 [ 2748.652671]??process_one_work+0x206/0x6a0 [ 2748.652709]??worker_thread+0x49/0x4a0 [ 2748.652745]??kthread+0x107/0x140 [ 2748.652854]??ret_from_fork+0x2e/0x40 [ 2748.652891] Code: ff 0f 1f 40 00 55 48 89 e5 41 57 41 56 41 55 41 54 53 48 83 c4 80 8b 87 58 03 00 00 48 8b 9e b0 00 00 00 85 c0 0f 84 8b 04 00 00 <48> 8b 83 d0 00 00 00 48 85 c0 0f 84 63 04 00 00 48 83 e8 10 48? [ 2748.653049] RIP: __bfq_insert_request+0x26/0x650 [bfq_mq_iosched] RSP: ffffc90003b4f9d8 [ 2748.653090] CR2: 00000000000000d0 The crash address corresponds to the following source code according to gdb: (gdb) list *(__bfq_insert_request+0x26) 0xd6f6 is in __bfq_insert_request (block/bfq-mq-iosched.c:4430). 4425 4426 ???static void __bfq_insert_request(struct bfq_data *bfqd, struct request *rq) 4427 ???{ 4428 ???????????struct bfq_queue *bfqq = RQ_BFQQ(rq), *new_bfqq; 4429 4430 ???????????assert_spin_locked(&bfqd->lock); 4431 4432 ???????????bfq_log_bfqq(bfqd, bfqq, "__insert_req: rq %p bfqq %p", rq, bfqq); 4433 4434 ???????????/* Bart.