From patchwork Tue Jul 17 14:16:10 2012 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Lauri Hintsala X-Patchwork-Id: 1205291 Return-Path: X-Original-To: patchwork-linux-arm@patchwork.kernel.org Delivered-To: patchwork-process-083081@patchwork2.kernel.org Received: from merlin.infradead.org (merlin.infradead.org [205.233.59.134]) by patchwork2.kernel.org (Postfix) with ESMTP id DE080DF25A for ; Tue, 17 Jul 2012 14:23:18 +0000 (UTC) Received: from localhost ([::1] helo=merlin.infradead.org) by merlin.infradead.org with esmtp (Exim 4.76 #1 (Red Hat Linux)) id 1Sr8cH-000589-ID; Tue, 17 Jul 2012 14:19:09 +0000 Received: from bluegiga.fi ([194.100.31.45] helo=blue-gw.bluegiga.fi) by merlin.infradead.org with esmtps (Exim 4.76 #1 (Red Hat Linux)) id 1Sr8Zp-0004qA-W0 for linux-arm-kernel@lists.infradead.org; Tue, 17 Jul 2012 14:16:47 +0000 Received: from bgtlh.bgt.local (unknown [10.1.1.28]) by blue-gw.bluegiga.fi (Postfix) with ESMTP id 6DBFD7BE2EF; Tue, 17 Jul 2012 17:16:36 +0300 (EEST) From: Lauri Hintsala To: Chris Ball Subject: [PATCH 2/2] mmc: mxs-mmc: fix deadlock caused by recursion loop Date: Tue, 17 Jul 2012 17:16:10 +0300 Message-Id: <1342534570-8293-3-git-send-email-lauri.hintsala@bluegiga.com> X-Mailer: git-send-email 1.7.9.5 In-Reply-To: <1342534570-8293-1-git-send-email-lauri.hintsala@bluegiga.com> References: <1342534570-8293-1-git-send-email-lauri.hintsala@bluegiga.com> X-Spam-Note: CRM114 invocation failed X-Spam-Score: -1.9 (-) X-Spam-Report: SpamAssassin version 3.3.2 on merlin.infradead.org summary: Content analysis details: (-1.9 points) pts rule name description ---- ---------------------- -------------------------------------------------- -1.9 BAYES_00 BODY: Bayes spam probability is 0 to 1% [score: 0.0000] Cc: Marek Vasut , koen.beel@barco.com, linux-mmc@vger.kernel.org, Wolfram Sang , attila@kinali.ch, Lauri Hintsala , veli-pekka.peltola@bluegiga.com, Shawn Guo , linux-arm-kernel@lists.infradead.org X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.14 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , MIME-Version: 1.0 Sender: linux-arm-kernel-bounces@lists.infradead.org Errors-To: linux-arm-kernel-bounces+patchwork-linux-arm=patchwork.kernel.org@lists.infradead.org Release the lock before mmc_signal_sdio_irq is called by mxs_mmc_enable_sdio_irq. Backtrace: [ 65.470000] ============================================= [ 65.470000] [ INFO: possible recursive locking detected ] [ 65.470000] 3.5.0-rc5 #2 Not tainted [ 65.470000] --------------------------------------------- [ 65.470000] ksdioirqd/mmc0/73 is trying to acquire lock: [ 65.470000] (&(&host->lock)->rlock#2){-.-...}, at: [] mxs_mmc_enable_sdio_irq+0x18/0xdc [mxs_mmc] [ 65.470000] [ 65.470000] but task is already holding lock: [ 65.470000] (&(&host->lock)->rlock#2){-.-...}, at: [] mxs_mmc_enable_sdio_irq+0x18/0xdc [mxs_mmc] [ 65.470000] [ 65.470000] other info that might help us debug this: [ 65.470000] Possible unsafe locking scenario: [ 65.470000] [ 65.470000] CPU0 [ 65.470000] ---- [ 65.470000] lock(&(&host->lock)->rlock#2); [ 65.470000] lock(&(&host->lock)->rlock#2); [ 65.470000] [ 65.470000] *** DEADLOCK *** [ 65.470000] [ 65.470000] May be due to missing lock nesting notation [ 65.470000] [ 65.470000] 1 lock held by ksdioirqd/mmc0/73: [ 65.470000] #0: (&(&host->lock)->rlock#2){-.-...}, at: [] mxs_mmc_enable_sdio_irq+0x18/0xdc [mxs_mmc] [ 65.470000] [ 65.470000] stack backtrace: [ 65.470000] [] (unwind_backtrace+0x0/0xf4) from [] (__lock_acquire+0x14f8/0x1b98) [ 65.470000] [] (__lock_acquire+0x14f8/0x1b98) from [] (lock_acquire+0xa0/0x108) [ 65.470000] [] (lock_acquire+0xa0/0x108) from [] (_raw_spin_lock_irqsave+0x48/0x5c) [ 65.470000] [] (_raw_spin_lock_irqsave+0x48/0x5c) from [] (mxs_mmc_enable_sdio_irq+0x18/0xdc [mxs_mmc]) [ 65.470000] [] (mxs_mmc_enable_sdio_irq+0x18/0xdc [mxs_mmc]) from [] (mxs_mmc_enable_sdio_irq+0xc8/0xdc [mxs_mmc]) [ 65.470000] [] (mxs_mmc_enable_sdio_irq+0xc8/0xdc [mxs_mmc]) from [] (sdio_irq_thread+0x1bc/0x274) [ 65.470000] [] (sdio_irq_thread+0x1bc/0x274) from [] (kthread+0x8c/0x98) [ 65.470000] [] (kthread+0x8c/0x98) from [] (kernel_thread_exit+0x0/0x8) [ 65.470000] BUG: spinlock lockup suspected on CPU#0, ksdioirqd/mmc0/73 [ 65.470000] lock: 0xc3358724, .magic: dead4ead, .owner: ksdioirqd/mmc0/73, .owner_cpu: 0 [ 65.470000] [] (unwind_backtrace+0x0/0xf4) from [] (do_raw_spin_lock+0x100/0x144) [ 65.470000] [] (do_raw_spin_lock+0x100/0x144) from [] (_raw_spin_lock_irqsave+0x50/0x5c) [ 65.470000] [] (_raw_spin_lock_irqsave+0x50/0x5c) from [] (mxs_mmc_enable_sdio_irq+0x18/0xdc [mxs_mmc]) [ 65.470000] [] (mxs_mmc_enable_sdio_irq+0x18/0xdc [mxs_mmc]) from [] (mxs_mmc_enable_sdio_irq+0xc8/0xdc [mxs_mmc]) [ 65.470000] [] (mxs_mmc_enable_sdio_irq+0xc8/0xdc [mxs_mmc]) from [] (sdio_irq_thread+0x1bc/0x274) [ 65.470000] [] (sdio_irq_thread+0x1bc/0x274) from [] (kthread+0x8c/0x98) [ 65.470000] [] (kthread+0x8c/0x98) from [] (kernel_thread_exit+0x0/0x8) Reported-by: Attila Kinali Signed-off-by: Lauri Hintsala Acked-by: Shawn Guo --- drivers/mmc/host/mxs-mmc.c | 10 +++++----- 1 file changed, 5 insertions(+), 5 deletions(-) diff --git a/drivers/mmc/host/mxs-mmc.c b/drivers/mmc/host/mxs-mmc.c index 20a0550..e1fd2c8 100644 --- a/drivers/mmc/host/mxs-mmc.c +++ b/drivers/mmc/host/mxs-mmc.c @@ -637,11 +637,6 @@ static void mxs_mmc_enable_sdio_irq(struct mmc_host *mmc, int enable) host->base + HW_SSP_CTRL0 + STMP_OFFSET_REG_SET); writel(BM_SSP_CTRL1_SDIO_IRQ_EN, host->base + HW_SSP_CTRL1(host) + STMP_OFFSET_REG_SET); - - if (readl(host->base + HW_SSP_STATUS(host)) & - BM_SSP_STATUS_SDIO_IRQ) - mmc_signal_sdio_irq(host->mmc); - } else { writel(BM_SSP_CTRL0_SDIO_IRQ_CHECK, host->base + HW_SSP_CTRL0 + STMP_OFFSET_REG_CLR); @@ -650,6 +645,11 @@ static void mxs_mmc_enable_sdio_irq(struct mmc_host *mmc, int enable) } spin_unlock_irqrestore(&host->lock, flags); + + if (enable && readl(host->base + HW_SSP_STATUS(host)) & + BM_SSP_STATUS_SDIO_IRQ) + mmc_signal_sdio_irq(host->mmc); + } static const struct mmc_host_ops mxs_mmc_ops = {