On Thu, May 21, 2015 at 11:26 AM, Andre Przywara [off-list ref] wrote:

+static void pl011_enable_interrupts(struct uart_amba_port *uap)
+{
+       spin_lock_irq(&uap->port.lock);
+
+       /* Clear out any spuriously appearing RX interrupts */
+       writew(UART011_RTIS | UART011_RXIS,
+              uap->port.membase + UART011_ICR);
+       uap->im = UART011_RTIM;
+       if (!pl011_dma_rx_running(uap))
+               uap->im |= UART011_RXIM;
+       writew(uap->im, uap->port.membase + UART011_IMSC);
+       spin_unlock_irq(&uap->port.lock);
+}

Shouldn't this function be using spin_lock_irqsave() and
spin_unlock_irqrestore()?  If interrupts are generally disabled before
calling this function, then they will be enabled by the
spin_unlock_irq() call, and I don't think we want that.  This function
is only supposed to enable pl011 interrupts, not all interrupts.

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