From 2836766a9d0bd02c66073f8dd44796e6cc23848d Mon Sep 17 00:00:00 2001 From: Krzysztof Kozlowski Date: Mon, 5 Jan 2015 10:50:15 +0100 Subject: [PATCH] mmc: sdhci: Fix sleep in atomic after inserting SD card Sleep in atomic context happened on Trats2 board after inserting or removing SD card because mmc_gpio_get_cd() was called under spin lock. Fix this by moving card detection earlier, before acquiring spin lock. The mmc_gpio_get_cd() call does not have to be protected by spin lock because it does not access any sdhci internal data. The sdhci_do_get_cd() call access host flags (SDHCI_DEVICE_DEAD). After moving it out side of spin lock it could theoretically race with driver removal but still there is no actual protection against manual card eject. Dmesg after inserting SD card: [ 41.663414] BUG: sleeping function called from invalid context at drivers/gpio/gpiolib.c:1511 [ 41.670469] in_atomic(): 1, irqs_disabled(): 128, pid: 30, name: kworker/u8:1 [ 41.677580] INFO: lockdep is turned off. [ 41.681486] irq event stamp: 61972 [ 41.684872] hardirqs last enabled at (61971): [] _raw_spin_unlock_irq+0x24/0x5c [ 41.693118] hardirqs last disabled at (61972): [] _raw_spin_lock_irq+0x18/0x54 [ 41.701190] softirqs last enabled at (61648): [] __do_softirq+0x234/0x2c8 [ 41.708914] softirqs last disabled at (61631): [] irq_exit+0xd0/0x114 [ 41.716206] Preemption disabled at:[< (null)>] (null) [ 41.721500] [ 41.722985] CPU: 3 PID: 30 Comm: kworker/u8:1 Tainted: G W 3.18.0-rc5-next-20141121 #883 [ 41.732111] Workqueue: kmmcd mmc_rescan [ 41.735945] [] (unwind_backtrace) from [] (show_stack+0x10/0x14) [ 41.743661] [] (show_stack) from [] (dump_stack+0x70/0xbc) [ 41.750867] [] (dump_stack) from [] (gpiod_get_raw_value_cansleep+0x18/0x30) [ 41.759628] [] (gpiod_get_raw_value_cansleep) from [] (mmc_gpio_get_cd+0x38/0x58) [ 41.768821] [] (mmc_gpio_get_cd) from [] (sdhci_request+0x50/0x1a4) [ 41.776808] [] (sdhci_request) from [] (mmc_start_request+0x138/0x268) [ 41.785051] [] (mmc_start_request) from [] (mmc_wait_for_req+0x58/0x1a0) [ 41.793469] [] (mmc_wait_for_req) from [] (mmc_wait_for_cmd+0x58/0x78) [ 41.801714] [] (mmc_wait_for_cmd) from [] (mmc_io_rw_direct_host+0x98/0x124) [ 41.810480] [] (mmc_io_rw_direct_host) from [] (sdio_reset+0x2c/0x64) [ 41.818641] [] (sdio_reset) from [] (mmc_rescan+0x254/0x2e4) [ 41.826028] [] (mmc_rescan) from [] (process_one_work+0x180/0x3f4) [ 41.833920] [] (process_one_work) from [] (worker_thread+0x34/0x4b0) [ 41.841991] [] (worker_thread) from [] (kthread+0xe4/0x104) [ 41.849285] [] (kthread) from [] (ret_from_fork+0x14/0x2c) [ 42.038276] mmc0: new high speed SDHC card at address 1234 Signed-off-by: Krzysztof Kozlowski Fixes: 94144a465dd0 ("mmc: sdhci: add get_cd() implementation") Cc: Signed-off-by: Ulf Hansson --- drivers/mmc/host/sdhci.c | 8 ++++++-- 1 file changed, 6 insertions(+), 2 deletions(-) diff --git a/drivers/mmc/host/sdhci.c b/drivers/mmc/host/sdhci.c index 398e9e496736..1453cd127921 100644 --- a/drivers/mmc/host/sdhci.c +++ b/drivers/mmc/host/sdhci.c @@ -1351,6 +1351,8 @@ static void sdhci_request(struct mmc_host *mmc, struct mmc_request *mrq) sdhci_runtime_pm_get(host); + present = mmc_gpio_get_cd(host->mmc); + spin_lock_irqsave(&host->lock, flags); WARN_ON(host->mrq != NULL); @@ -1379,7 +1381,6 @@ static void sdhci_request(struct mmc_host *mmc, struct mmc_request *mrq) * zero: cd-gpio is used, and card is removed * one: cd-gpio is used, and card is present */ - present = mmc_gpio_get_cd(host->mmc); if (present < 0) { /* If polling, assume that the card is always present. */ if (host->quirks & SDHCI_QUIRK_BROKEN_CARD_DETECTION) @@ -2126,15 +2127,18 @@ static void sdhci_card_event(struct mmc_host *mmc) { struct sdhci_host *host = mmc_priv(mmc); unsigned long flags; + int present; /* First check if client has provided their own card event */ if (host->ops->card_event) host->ops->card_event(host); + present = sdhci_do_get_cd(host); + spin_lock_irqsave(&host->lock, flags); /* Check host->mrq first in case we are runtime suspended */ - if (host->mrq && !sdhci_do_get_cd(host)) { + if (host->mrq && !present) { pr_err("%s: Card removed during transfer!\n", mmc_hostname(host->mmc)); pr_err("%s: Resetting controller.\n", -- 2.34.1