3.4.106-rt132-rc1 stable review patch. If anyone has any objections, please let me know. ------------------ From: Sebastian Andrzej Siewior <bigeasy@xxxxxxxxxxxxx> This patch converts gpio_bank.lock from a spin_lock into a raw_spin_lock. The call path is to access this lock is always under a raw_spin_lock, for instance - __setup_irq() holds &desc->lock with irq off + __irq_set_trigger() + omap_gpio_irq_type() - handle_level_irq() (runs with irqs off therefore raw locks) + mask_ack_irq() + omap_gpio_mask_irq() This fixes the obvious backtrace on -RT. However the locking vs context is not and this is not limited to -RT: - omap_gpio_irq_type() is called with IRQ off and has an conditional call to pm_runtime_get_sync() which may sleep. Either it may happen or it may not happen but pm_runtime_get_sync() should not be called with irqs off. - omap_gpio_debounce() is holding the lock with IRQs off. + omap2_set_gpio_debounce() + clk_prepare_enable() + clk_prepare() this one might sleep. The number of users of gpiod_set_debounce() / gpio_set_debounce() looks low but still this is not good. Cc: stable-rt@xxxxxxxxxxxxxxx Signed-off-by: Sebastian Andrzej Siewior <bigeasy@xxxxxxxxxxxxx> Signed-off-by: Steven Rostedt <rostedt@xxxxxxxxxxx> --- drivers/gpio/gpio-omap.c | 76 ++++++++++++++++++++++++------------------------ 1 file changed, 38 insertions(+), 38 deletions(-) diff --git a/drivers/gpio/gpio-omap.c b/drivers/gpio/gpio-omap.c index 4461540653a8..58ba0595c9a2 100644 --- a/drivers/gpio/gpio-omap.c +++ b/drivers/gpio/gpio-omap.c @@ -67,7 +67,7 @@ struct gpio_bank { u32 saved_risingdetect; u32 level_mask; u32 toggle_mask; - spinlock_t lock; + raw_spinlock_t lock; struct gpio_chip chip; struct clk *dbck; u32 mod_usage; @@ -395,9 +395,9 @@ static int gpio_irq_type(struct irq_data *d, unsigned type) (type & (IRQ_TYPE_LEVEL_LOW|IRQ_TYPE_LEVEL_HIGH))) return -EINVAL; - spin_lock_irqsave(&bank->lock, flags); + raw_spin_lock_irqsave(&bank->lock, flags); retval = _set_gpio_triggering(bank, GPIO_INDEX(bank, gpio), type); - spin_unlock_irqrestore(&bank->lock, flags); + raw_spin_unlock_irqrestore(&bank->lock, flags); if (type & (IRQ_TYPE_LEVEL_LOW | IRQ_TYPE_LEVEL_HIGH)) __irq_set_handler_locked(d->irq, handle_level_irq); @@ -514,14 +514,14 @@ static int _set_gpio_wakeup(struct gpio_bank *bank, int gpio, int enable) return -EINVAL; } - spin_lock_irqsave(&bank->lock, flags); + raw_spin_lock_irqsave(&bank->lock, flags); if (enable) bank->suspend_wakeup |= gpio_bit; else bank->suspend_wakeup &= ~gpio_bit; __raw_writel(bank->suspend_wakeup, bank->base + bank->regs->wkup_en); - spin_unlock_irqrestore(&bank->lock, flags); + raw_spin_unlock_irqrestore(&bank->lock, flags); return 0; } @@ -555,7 +555,7 @@ static int omap_gpio_request(struct gpio_chip *chip, unsigned offset) if (!bank->mod_usage) pm_runtime_get_sync(bank->dev); - spin_lock_irqsave(&bank->lock, flags); + raw_spin_lock_irqsave(&bank->lock, flags); /* Set trigger to none. You need to enable the desired trigger with * request_irq() or set_irq_type(). */ @@ -581,7 +581,7 @@ static int omap_gpio_request(struct gpio_chip *chip, unsigned offset) bank->mod_usage |= 1 << offset; - spin_unlock_irqrestore(&bank->lock, flags); + raw_spin_unlock_irqrestore(&bank->lock, flags); return 0; } @@ -592,7 +592,7 @@ static void omap_gpio_free(struct gpio_chip *chip, unsigned offset) void __iomem *base = bank->base; unsigned long flags; - spin_lock_irqsave(&bank->lock, flags); + raw_spin_lock_irqsave(&bank->lock, flags); if (bank->regs->wkup_en) { /* Disable wake-up during idle for dynamic tick */ @@ -615,7 +615,7 @@ static void omap_gpio_free(struct gpio_chip *chip, unsigned offset) } _reset_gpio(bank, bank->chip.base + offset); - spin_unlock_irqrestore(&bank->lock, flags); + raw_spin_unlock_irqrestore(&bank->lock, flags); /* * If this is the last gpio to be freed in the bank, @@ -720,9 +720,9 @@ static void gpio_irq_shutdown(struct irq_data *d) unsigned int gpio = irq_to_gpio(bank, d->irq); unsigned long flags; - spin_lock_irqsave(&bank->lock, flags); + raw_spin_lock_irqsave(&bank->lock, flags); _reset_gpio(bank, gpio); - spin_unlock_irqrestore(&bank->lock, flags); + raw_spin_unlock_irqrestore(&bank->lock, flags); } static void gpio_ack_irq(struct irq_data *d) @@ -739,10 +739,10 @@ static void gpio_mask_irq(struct irq_data *d) unsigned int gpio = irq_to_gpio(bank, d->irq); unsigned long flags; - spin_lock_irqsave(&bank->lock, flags); + raw_spin_lock_irqsave(&bank->lock, flags); _set_gpio_irqenable(bank, gpio, 0); _set_gpio_triggering(bank, GPIO_INDEX(bank, gpio), IRQ_TYPE_NONE); - spin_unlock_irqrestore(&bank->lock, flags); + raw_spin_unlock_irqrestore(&bank->lock, flags); } static void gpio_unmask_irq(struct irq_data *d) @@ -753,7 +753,7 @@ static void gpio_unmask_irq(struct irq_data *d) u32 trigger = irqd_get_trigger_type(d); unsigned long flags; - spin_lock_irqsave(&bank->lock, flags); + raw_spin_lock_irqsave(&bank->lock, flags); if (trigger) _set_gpio_triggering(bank, GPIO_INDEX(bank, gpio), trigger); @@ -765,7 +765,7 @@ static void gpio_unmask_irq(struct irq_data *d) } _set_gpio_irqenable(bank, gpio, 1); - spin_unlock_irqrestore(&bank->lock, flags); + raw_spin_unlock_irqrestore(&bank->lock, flags); } static struct irq_chip gpio_irq_chip = { @@ -788,10 +788,10 @@ static int omap_mpuio_suspend_noirq(struct device *dev) OMAP_MPUIO_GPIO_MASKIT / bank->stride; unsigned long flags; - spin_lock_irqsave(&bank->lock, flags); + raw_spin_lock_irqsave(&bank->lock, flags); bank->saved_wakeup = __raw_readl(mask_reg); __raw_writel(0xffff & ~bank->suspend_wakeup, mask_reg); - spin_unlock_irqrestore(&bank->lock, flags); + raw_spin_unlock_irqrestore(&bank->lock, flags); return 0; } @@ -804,9 +804,9 @@ static int omap_mpuio_resume_noirq(struct device *dev) OMAP_MPUIO_GPIO_MASKIT / bank->stride; unsigned long flags; - spin_lock_irqsave(&bank->lock, flags); + raw_spin_lock_irqsave(&bank->lock, flags); __raw_writel(bank->saved_wakeup, mask_reg); - spin_unlock_irqrestore(&bank->lock, flags); + raw_spin_unlock_irqrestore(&bank->lock, flags); return 0; } @@ -849,9 +849,9 @@ static int gpio_input(struct gpio_chip *chip, unsigned offset) unsigned long flags; bank = container_of(chip, struct gpio_bank, chip); - spin_lock_irqsave(&bank->lock, flags); + raw_spin_lock_irqsave(&bank->lock, flags); _set_gpio_direction(bank, offset, 1); - spin_unlock_irqrestore(&bank->lock, flags); + raw_spin_unlock_irqrestore(&bank->lock, flags); return 0; } @@ -882,10 +882,10 @@ static int gpio_output(struct gpio_chip *chip, unsigned offset, int value) unsigned long flags; bank = container_of(chip, struct gpio_bank, chip); - spin_lock_irqsave(&bank->lock, flags); + raw_spin_lock_irqsave(&bank->lock, flags); bank->set_dataout(bank, offset, value); _set_gpio_direction(bank, offset, 0); - spin_unlock_irqrestore(&bank->lock, flags); + raw_spin_unlock_irqrestore(&bank->lock, flags); return 0; } @@ -903,9 +903,9 @@ static int gpio_debounce(struct gpio_chip *chip, unsigned offset, dev_err(bank->dev, "Could not get gpio dbck\n"); } - spin_lock_irqsave(&bank->lock, flags); + raw_spin_lock_irqsave(&bank->lock, flags); _set_gpio_debounce(bank, offset, debounce); - spin_unlock_irqrestore(&bank->lock, flags); + raw_spin_unlock_irqrestore(&bank->lock, flags); return 0; } @@ -916,9 +916,9 @@ static void gpio_set(struct gpio_chip *chip, unsigned offset, int value) unsigned long flags; bank = container_of(chip, struct gpio_bank, chip); - spin_lock_irqsave(&bank->lock, flags); + raw_spin_lock_irqsave(&bank->lock, flags); bank->set_dataout(bank, offset, value); - spin_unlock_irqrestore(&bank->lock, flags); + raw_spin_unlock_irqrestore(&bank->lock, flags); } static int gpio_2irq(struct gpio_chip *chip, unsigned offset) @@ -1109,7 +1109,7 @@ static int __devinit omap_gpio_probe(struct platform_device *pdev) else bank->set_dataout = _set_gpio_dataout_mask; - spin_lock_init(&bank->lock); + raw_spin_lock_init(&bank->lock); /* Static mapping, never released */ res = platform_get_resource(pdev, IORESOURCE_MEM, 0); @@ -1169,11 +1169,11 @@ static int omap_gpio_suspend(struct device *dev) wakeup_enable = bank->base + bank->regs->wkup_en; - spin_lock_irqsave(&bank->lock, flags); + raw_spin_lock_irqsave(&bank->lock, flags); bank->saved_wakeup = __raw_readl(wakeup_enable); _gpio_rmw(base, bank->regs->wkup_en, 0xffffffff, 0); _gpio_rmw(base, bank->regs->wkup_en, bank->suspend_wakeup, 1); - spin_unlock_irqrestore(&bank->lock, flags); + raw_spin_unlock_irqrestore(&bank->lock, flags); return 0; } @@ -1191,10 +1191,10 @@ static int omap_gpio_resume(struct device *dev) if (!bank->regs->wkup_en || !bank->saved_wakeup) return 0; - spin_lock_irqsave(&bank->lock, flags); + raw_spin_lock_irqsave(&bank->lock, flags); _gpio_rmw(base, bank->regs->wkup_en, 0xffffffff, 0); _gpio_rmw(base, bank->regs->wkup_en, bank->saved_wakeup, 1); - spin_unlock_irqrestore(&bank->lock, flags); + raw_spin_unlock_irqrestore(&bank->lock, flags); return 0; } @@ -1211,7 +1211,7 @@ static int omap_gpio_runtime_suspend(struct device *dev) unsigned long flags; u32 wake_low, wake_hi; - spin_lock_irqsave(&bank->lock, flags); + raw_spin_lock_irqsave(&bank->lock, flags); /* * Only edges can generate a wakeup event to the PRCM. @@ -1263,7 +1263,7 @@ update_gpio_context_count: bank->get_context_loss_count(bank->dev); _gpio_dbck_disable(bank); - spin_unlock_irqrestore(&bank->lock, flags); + raw_spin_unlock_irqrestore(&bank->lock, flags); return 0; } @@ -1276,7 +1276,7 @@ static int omap_gpio_runtime_resume(struct device *dev) u32 l = 0, gen, gen0, gen1; unsigned long flags; - spin_lock_irqsave(&bank->lock, flags); + raw_spin_lock_irqsave(&bank->lock, flags); _gpio_dbck_enable(bank); /* @@ -1291,7 +1291,7 @@ static int omap_gpio_runtime_resume(struct device *dev) bank->base + bank->regs->risingdetect); if (!bank->workaround_enabled) { - spin_unlock_irqrestore(&bank->lock, flags); + raw_spin_unlock_irqrestore(&bank->lock, flags); return 0; } @@ -1302,7 +1302,7 @@ static int omap_gpio_runtime_resume(struct device *dev) !context_lost_cnt_after) { omap_gpio_restore_context(bank); } else { - spin_unlock_irqrestore(&bank->lock, flags); + raw_spin_unlock_irqrestore(&bank->lock, flags); return 0; } } @@ -1361,7 +1361,7 @@ static int omap_gpio_runtime_resume(struct device *dev) } bank->workaround_enabled = false; - spin_unlock_irqrestore(&bank->lock, flags); + raw_spin_unlock_irqrestore(&bank->lock, flags); return 0; } -- 2.1.4 -- To unsubscribe from this list: send the line "unsubscribe stable-rt" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html