From 2b35bd83467df6f8284b9148d6f768148c3a5e5f Mon Sep 17 00:00:00 2001 From: Aisheng Dong Date: Mon, 23 Dec 2013 19:13:04 +0800 Subject: mmc: sdhci: fix lockdep error in tuning routine 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 Signed-off-by: Dong Aisheng Cc: stable Signed-off-by: Chris Ball diff --git a/drivers/mmc/host/sdhci.c b/drivers/mmc/host/sdhci.c index ec3eb30..0a1893a 100644 --- a/drivers/mmc/host/sdhci.c +++ b/drivers/mmc/host/sdhci.c @@ -1857,12 +1857,12 @@ 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); @@ -1882,15 +1882,13 @@ 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; @@ -1963,15 +1961,12 @@ 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 " @@ -2046,8 +2041,7 @@ 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; -- cgit v0.10.2