From patchwork Mon Dec 23 11:13:04 2013 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Aisheng Dong X-Patchwork-Id: 3396511 Return-Path: X-Original-To: patchwork-linux-mmc@patchwork.kernel.org Delivered-To: patchwork-parsemail@patchwork1.web.kernel.org Received: from mail.kernel.org (mail.kernel.org [198.145.19.201]) by patchwork1.web.kernel.org (Postfix) with ESMTP id 484AD9F386 for ; Mon, 23 Dec 2013 11:44:09 +0000 (UTC) Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id 2268B204DE for ; Mon, 23 Dec 2013 11:44:08 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id DE9AF204E1 for ; Mon, 23 Dec 2013 11:44:06 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757271Ab3LWLnw (ORCPT ); Mon, 23 Dec 2013 06:43:52 -0500 Received: from mail-db8lp0184.outbound.messaging.microsoft.com ([213.199.154.184]:29606 "EHLO db8outboundpool.messaging.microsoft.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1757270Ab3LWLnu (ORCPT ); Mon, 23 Dec 2013 06:43:50 -0500 Received: from mail29-db8-R.bigfish.com (10.174.8.240) by DB8EHSOBE032.bigfish.com (10.174.4.95) with Microsoft SMTP Server id 14.1.225.22; Mon, 23 Dec 2013 11:43:48 +0000 Received: from mail29-db8 (localhost [127.0.0.1]) by mail29-db8-R.bigfish.com (Postfix) with ESMTP id 75B4D1EC00DB; Mon, 23 Dec 2013 11:43:48 +0000 (UTC) X-Forefront-Antispam-Report: CIP:70.37.183.190; KIP:(null); UIP:(null); IPV:NLI; H:mail.freescale.net; RD:none; EFVD:NLI X-SpamScore: -7 X-BigFish: VS-7(zz1403Rzz1f42h2148h208ch1ee6h1de0h1fdah2073h2146h1202h1e76h2189h1d1ah1d2ah1fc6h1082kzz1de098h8275bh8275dh1de097hz2dh2a8h839hd24he5bhf0ah1288h12a5h12a9h12bdh12e5h137ah139eh13b6h1441h1504h1537h162dh1631h1758h1898h18e1h1946h19b5h1ad9h1b0ah1b2fh2222h224fh1fb3h1d0ch1d2eh1d3fh1dc1h1dfeh1dffh1e23h1fe8h1ff5h2218h2216h226dh22d0h2327h2336h1155h) Received: from mail29-db8 (localhost.localdomain [127.0.0.1]) by mail29-db8 (MessageSwitch) id 1387799027651347_18020; Mon, 23 Dec 2013 11:43:47 +0000 (UTC) Received: from DB8EHSMHS005.bigfish.com (unknown [10.174.8.253]) by mail29-db8.bigfish.com (Postfix) with ESMTP id 2952F180005F; Mon, 23 Dec 2013 11:43:44 +0000 (UTC) Received: from mail.freescale.net (70.37.183.190) by DB8EHSMHS005.bigfish.com (10.174.4.15) with Microsoft SMTP Server (TLS) id 14.16.227.3; Mon, 23 Dec 2013 11:43:42 +0000 Received: from tx30smr01.am.freescale.net (10.81.153.31) by 039-SN1MMR1-004.039d.mgd.msft.net (10.84.1.14) with Microsoft SMTP Server (TLS) id 14.3.158.2; Mon, 23 Dec 2013 11:43:40 +0000 Received: from shlinux2.ap.freescale.net (shlinux2.ap.freescale.net [10.192.224.44]) by tx30smr01.am.freescale.net (8.14.3/8.14.0) with ESMTP id rBNBhakp005443; Mon, 23 Dec 2013 04:43:38 -0700 From: Dong Aisheng To: CC: , , , , , Subject: [PATCH 1/1] mmc: sdhci: fix lockdep error on tunning routine Date: Mon, 23 Dec 2013 19:13:04 +0800 Message-ID: <1387797184-18958-1-git-send-email-b29396@freescale.com> X-Mailer: git-send-email 1.7.2.rc3 MIME-Version: 1.0 X-OriginatorOrg: freescale.com X-FOPE-CONNECTOR: Id%0$Dn%*$RO%0$TLS%0$FQDN%$TlsDn% X-FOPE-CONNECTOR: Id%0$Dn%FREESCALE.MAIL.ONMICROSOFT.COM$RO%1$TLS%0$FQDN%$TlsDn% Sender: linux-mmc-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-mmc@vger.kernel.org X-Spam-Status: No, score=-6.2 required=5.0 tests=BAYES_00, RCVD_IN_DNSWL_HI, RP_MATCHES_RCVD, UNPARSEABLE_RELAY, UNRESOLVED_TEMPLATE autolearn=ham version=3.3.1 X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on mail.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP The sdhci_execute_tuning routine gets lock separately by disable_irq(host->irq); spin_lock(&host->lock); It will cause the following lockdep error message since the &host->lock could also be got in irq context. Use spin_lock_irqsave/spin_unlock_restore instead to get rid of this error message. [ INFO: inconsistent lock state ] 3.13.0-rc1+ #287 Not tainted --------------------------------- inconsistent {IN-HARDIRQ-W} -> {HARDIRQ-ON-W} usage. kworker/u2:1/33 [HC0[0]:SC0[0]:HE1:SE1] takes: (&(&host->lock)->rlock){?.-...}, at: [<8045f7f4>] sdhci_execute_tuning+0x4c/0x710 {IN-HARDIRQ-W} state was registered at: [<8005f030>] mark_lock+0x140/0x6ac [<80060760>] __lock_acquire+0xb30/0x1cbc [<800620d0>] lock_acquire+0x70/0x84 [<8061d1c8>] _raw_spin_lock+0x30/0x40 [<804605cc>] sdhci_irq+0x24/0xa68 [<8006b1d4>] handle_irq_event_percpu+0x54/0x18c [<8006b350>] handle_irq_event+0x44/0x64 [<8006e50c>] handle_fasteoi_irq+0xa0/0x170 [<8006a8f0>] generic_handle_irq+0x30/0x44 [<8000f238>] handle_IRQ+0x54/0xbc [<8000864c>] gic_handle_irq+0x30/0x64 [<80013024>] __irq_svc+0x44/0x5c [<80329bf4>] dev_vprintk_emit+0x50/0x58 [<80329c24>] dev_printk_emit+0x28/0x30 [<80329fec>] __dev_printk+0x4c/0x90 [<8032a180>] dev_err+0x3c/0x48 [<802dd4f0>] _regulator_get+0x158/0x1cc [<802dd5b4>] regulator_get_optional+0x18/0x1c [<80461df4>] sdhci_add_host+0x42c/0xbd8 [<80464820>] sdhci_esdhc_imx_probe+0x378/0x67c [<8032ee88>] platform_drv_probe+0x20/0x50 [<8032d48c>] driver_probe_device+0x118/0x234 [<8032d690>] __driver_attach+0x9c/0xa0 [<8032b89c>] bus_for_each_dev+0x68/0x9c [<8032cf44>] driver_attach+0x20/0x28 [<8032cbc8>] bus_add_driver+0x148/0x1f4 [<8032dce0>] driver_register+0x80/0x100 [<8032ee54>] __platform_driver_register+0x50/0x64 [<8084b094>] sdhci_esdhc_imx_driver_init+0x18/0x20 [<80008980>] do_one_initcall+0x108/0x16c [<8081cca4>] kernel_init_freeable+0x10c/0x1d0 [<80611b28>] kernel_init+0x10/0x120 [<8000e9c8>] ret_from_fork+0x14/0x2c irq event stamp: 805 hardirqs last enabled at (805): [<8061d43c>] _raw_spin_unlock_irqrestore+0x38/0x4c hardirqs last disabled at (804): [<8061d2c8>] _raw_spin_lock_irqsave+0x24/0x54 softirqs last enabled at (570): [<8002b824>] __do_softirq+0x1c4/0x290 softirqs last disabled at (561): [<8002bcf4>] irq_exit+0xb4/0x10c other info that might help us debug this: Possible unsafe locking scenario: CPU0 ---- lock(&(&host->lock)->rlock); lock(&(&host->lock)->rlock); *** DEADLOCK *** 2 locks held by kworker/u2:1/33: #0: (kmmcd){.+.+..}, at: [<8003db18>] process_one_work+0x128/0x468 #1: ((&(&host->detect)->work)){+.+...}, at: [<8003db18>] process_one_work+0x128/0x468 stack backtrace: CPU: 0 PID: 33 Comm: kworker/u2:1 Not tainted 3.13.0-rc1+ #287 Workqueue: kmmcd mmc_rescan Backtrace: [<80012160>] (dump_backtrace+0x0/0x10c) from [<80012438>] (show_stack+0x18/0x1c) r6:bfad0900 r5:00000000 r4:8088ecc8 r3:bfad0900 [<80012420>] (show_stack+0x0/0x1c) from [<806169ec>] (dump_stack+0x84/0x9c) [<80616968>] (dump_stack+0x0/0x9c) from [<806147b4>] (print_usage_bug+0x260/0x2d0) r5:8076ba88 r4:80977410 [<80614554>] (print_usage_bug+0x0/0x2d0) from [<8005f0d0>] (mark_lock+0x1e0/0x6ac) r9:8005e678 r8:00000000 r7:bfad0900 r6:00001015 r5:bfad0cd0 r4:00000002 [<8005eef0>] (mark_lock+0x0/0x6ac) from [<80060234>] (__lock_acquire+0x604/0x1cbc) [<8005fc30>] (__lock_acquire+0x0/0x1cbc) from [<800620d0>] (lock_acquire+0x70/0x84) [<80062060>] (lock_acquire+0x0/0x84) from [<8061d1c8>] (_raw_spin_lock+0x30/0x40) r7:00000000 r6:bfb63000 r5:00000000 r4:bfb60568 [<8061d198>] (_raw_spin_lock+0x0/0x40) from [<8045f7f4>] (sdhci_execute_tuning+0x4c/0x710) r4:bfb60000 [<8045f7a8>] (sdhci_execute_tuning+0x0/0x710) from [<80453454>] (mmc_sd_init_card+0x5f8/0x660) [<80452e5c>] (mmc_sd_init_card+0x0/0x660) from [<80453748>] (mmc_attach_sd+0xb4/0x180) r9:bf92d400 r8:8065f364 r7:00061a80 r6:bfb60000 r5:8065f358 r4:bfb60000 [<80453694>] (mmc_attach_sd+0x0/0x180) from [<8044d9f8>] (mmc_rescan+0x284/0x2f0) r5:8065f358 r4:bfb602f8 [<8044d774>] (mmc_rescan+0x0/0x2f0) from [<8003db94>] (process_one_work+0x1a4/0x468) r8:00000000 r7:bfb55eb0 r6:bf80dc00 r5:bfb602f8 r4:bfb35980 r3:8044d774 [<8003d9f0>] (process_one_work+0x0/0x468) from [<8003e850>] (worker_thread+0x118/0x3e0) [<8003e738>] (worker_thread+0x0/0x3e0) from [<80044de0>] (kthread+0xd4/0xf0) [<80044d0c>] (kthread+0x0/0xf0) from [<8000e9c8>] (ret_from_fork+0x14/0x2c) r7:00000000 r6:00000000 r5:80044d0c r4:bfb37b40 Cc: Peter Zijlstra Cc: Chris Ball Cc: Shawn Guo Signed-off-by: Dong Aisheng --- It's strange that this issue did not happen on kernel 3.10.17 with the same code. And looking at the code, before call spin_lock we already disable the mmc controller irq, per on my understanding, the deadlock given by lockdep may not be able to happen(pls fix me if wrong). May the lockdep not track the specific irq disable? Copy lockdep guy to comment. --- drivers/mmc/host/sdhci.c | 20 +++++++------------- 1 files changed, 7 insertions(+), 13 deletions(-) diff --git a/drivers/mmc/host/sdhci.c b/drivers/mmc/host/sdhci.c index a104bb1..c5d5f53 100644 --- a/drivers/mmc/host/sdhci.c +++ b/drivers/mmc/host/sdhci.c @@ -1876,12 +1876,12 @@ static int sdhci_execute_tuning(struct mmc_host *mmc, u32 opcode) unsigned long timeout; int err = 0; bool requires_tuning_nonuhs = false; + unsigned long flags; host = mmc_priv(mmc); sdhci_runtime_pm_get(host); - disable_irq(host->irq); - spin_lock(&host->lock); + spin_lock_irqsave(&host->lock, flags); ctrl = sdhci_readw(host, SDHCI_HOST_CONTROL2); @@ -1901,15 +1901,13 @@ static int sdhci_execute_tuning(struct mmc_host *mmc, u32 opcode) requires_tuning_nonuhs) ctrl |= SDHCI_CTRL_EXEC_TUNING; else { - spin_unlock(&host->lock); - enable_irq(host->irq); + spin_unlock_irqrestore(&host->lock, flags); sdhci_runtime_pm_put(host); return 0; } if (host->ops->platform_execute_tuning) { - spin_unlock(&host->lock); - enable_irq(host->irq); + spin_unlock_irqrestore(&host->lock, flags); err = host->ops->platform_execute_tuning(host, opcode); sdhci_runtime_pm_put(host); return err; @@ -1982,15 +1980,12 @@ static int sdhci_execute_tuning(struct mmc_host *mmc, u32 opcode) host->cmd = NULL; host->mrq = NULL; - spin_unlock(&host->lock); - enable_irq(host->irq); - + spin_unlock_irqrestore(&host->lock, flags); /* Wait for Buffer Read Ready interrupt */ wait_event_interruptible_timeout(host->buf_ready_int, (host->tuning_done == 1), msecs_to_jiffies(50)); - disable_irq(host->irq); - spin_lock(&host->lock); + spin_lock_irqsave(&host->lock, flags); if (!host->tuning_done) { pr_info(DRIVER_NAME ": Timeout waiting for " @@ -2065,8 +2060,7 @@ out: err = 0; sdhci_clear_set_irqs(host, SDHCI_INT_DATA_AVAIL, ier); - spin_unlock(&host->lock); - enable_irq(host->irq); + spin_unlock_irqrestore(&host->lock, flags); sdhci_runtime_pm_put(host); return err;