From 0cfe17c2a90928f6bedd935188c8c7feea252c82 Mon Sep 17 00:00:00 2001 From: Daniel Kurtz Date: Mon, 16 Jul 2018 18:57:18 -0600 Subject: [PATCH] pinctrl/amd: only handle irq if it is pending and unmasked [ Upstream commit 8bbed1eef001fdfc0ee9595f64cc4f769d265af4 ] The AMD pinctrl driver demultiplexes GPIO interrupts and fires off their individual handlers. If one of these GPIO irqs is configured as a level interrupt, and its downstream handler is a threaded ONESHOT interrupt, the GPIO interrupt source is masked by handle_level_irq() until the eventual return of the threaded irq handler. During this time the level GPIO interrupt status will still report as high until the actual gpio source is cleared - both in the individual GPIO interrupt status bit (INTERRUPT_STS_OFF) and in its corresponding "WAKE_INT_STATUS_REG" bit. Thus, if another GPIO interrupt occurs during this time, amd_gpio_irq_handler() will see that the (masked-and-not-yet-cleared) level irq is still pending and incorrectly call its handler again. To fix this, have amd_gpio_irq_handler() check for both interrupts status and mask before calling generic_handle_irq(). Note: Is it possible that this bug was the source of the interrupt storm on Ryzen when using chained interrupts before commit ba714a9c1dea85 ("pinctrl/amd: Use regular interrupt instead of chained")? Signed-off-by: Daniel Kurtz Acked-by: Thomas Gleixner Signed-off-by: Linus Walleij Signed-off-by: Sasha Levin Signed-off-by: Greg Kroah-Hartman --- drivers/pinctrl/pinctrl-amd.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/drivers/pinctrl/pinctrl-amd.c b/drivers/pinctrl/pinctrl-amd.c index 433af328d981..b78f42abff2f 100644 --- a/drivers/pinctrl/pinctrl-amd.c +++ b/drivers/pinctrl/pinctrl-amd.c @@ -530,7 +530,8 @@ static irqreturn_t amd_gpio_irq_handler(int irq, void *dev_id) /* Each status bit covers four pins */ for (i = 0; i < 4; i++) { regval = readl(regs + i); - if (!(regval & PIN_IRQ_PENDING)) + if (!(regval & PIN_IRQ_PENDING) || + !(regval & BIT(INTERRUPT_MASK_OFF))) continue; irq = irq_find_mapping(gc->irqdomain, irqnr + i); generic_handle_irq(irq);