From fc108d24d3a6da63576a460e122fa1df0cbdea20 Mon Sep 17 00:00:00 2001 From: Lauri Hintsala Date: Tue, 17 Jul 2012 17:16:10 +0300 Subject: [PATCH] mmc: mxs-mmc: fix deadlock caused by recursion loop 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 Cc: stable Signed-off-by: Chris Ball --- 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 e62e58e5053d..ad3fcea1269e 100644 --- a/drivers/mmc/host/mxs-mmc.c +++ b/drivers/mmc/host/mxs-mmc.c @@ -644,11 +644,6 @@ 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); @@ -657,6 +652,11 @@ 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 = { -- 2.20.1