On Mon, Jan 28, 2019 at 01:25:56PM -0500, Chris Brandt wrote:
> Since IRQs might be muxed on some parts, we need to pay attention when we
> are freeing them.
> Otherwise we get the ugly WARNING "Trying to free already-free IRQ 20".
>
> Fixes: 628c534ae735 ("serial: sh-sci: Improve support for separate TEI and DRI interrupts")
> Signed-off-by: Chris Brandt <chris.brandt@xxxxxxxxxxx>
Reviewed-by: Simon Horman <horms+renesas@xxxxxxxxxxxx>
> ---
> v2:
> * fix bad commit grammer
s/grammer/grammar/ :)
> ---
> drivers/tty/serial/sh-sci.c | 9 ++++++++-
> 1 file changed, 8 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/tty/serial/sh-sci.c b/drivers/tty/serial/sh-sci.c
> index cb3d5d37674f..060fcd42b6d5 100644
> --- a/drivers/tty/serial/sh-sci.c
> +++ b/drivers/tty/serial/sh-sci.c
> @@ -1936,7 +1936,7 @@ static int sci_request_irq(struct sci_port *port)
>
> static void sci_free_irq(struct sci_port *port)
> {
> - int i;
> + int i, j;
>
> /*
> * Intentionally in reverse order so we iterate over the muxed
> @@ -1952,6 +1952,13 @@ static void sci_free_irq(struct sci_port *port)
> if (unlikely(irq < 0))
> continue;
>
> + /* Check if already freed (irq was muxed) */
> + for (j = 0; j < i; j++)
> + if (port->irqs[j] == irq)
> + j = i + 1;
> + if (j > i)
> + continue;
> +
> free_irq(port->irqs[i], port);
> kfree(port->irqstr[i]);
>
> --
> 2.16.1
>
