On Tue, Jul 21, 2015 at 6:26 PM, Sebastian Andrzej Siewior <bigeasy@xxxxxxxxxxxxx> wrote: > 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. > > Acked-by: Javier Martinez Canillas <javier@xxxxxxxxxxxx> > Acked-by: Santosh Shilimkar <ssantosh@xxxxxxxxxx> > Signed-off-by: Sebastian Andrzej Siewior <bigeasy@xxxxxxxxxxxxx> Patch applied. Now this question appear in my head: Is drivers/gpio full of stuff that will not work with the -RT kernel, and is this a change that should be done mutatis mutandis on all the GPIO drivers? Yours, Linus Walleij -- To unsubscribe from this list: send the line "unsubscribe linux-omap" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
