RE: [PATCH net v2] net: dsa: mv88e6xxx: lock mutex when freeing IRQs

[David Laight]

From: Vivien Didelot
> Sent: 26 September 2017 19:57
> mv88e6xxx_g2_irq_free locks the registers mutex, but not
> mv88e6xxx_g1_irq_free, which results in a stack trace from
> assert_reg_lock when unloading the mv88e6xxx module. Fix this.
> 
> Fixes: 3460a5770ce9 ("net: dsa: mv88e6xxx: Mask g1 interrupts and free interrupt")
> Signed-off-by: Vivien Didelot <vivien.didelot@xxxxxxxxxxxxxxxxxxxx>
> ---
>  drivers/net/dsa/mv88e6xxx/chip.c | 2 ++
>  1 file changed, 2 insertions(+)
> 
> diff --git a/drivers/net/dsa/mv88e6xxx/chip.c b/drivers/net/dsa/mv88e6xxx/chip.c
> index c6678aa9b4ef..e7ff7483d2fb 100644
> --- a/drivers/net/dsa/mv88e6xxx/chip.c
> +++ b/drivers/net/dsa/mv88e6xxx/chip.c
> @@ -3947,7 +3947,9 @@ static void mv88e6xxx_remove(struct mdio_device *mdiodev)
>  	if (chip->irq > 0) {
>  		if (chip->info->g2_irqs > 0)
>  			mv88e6xxx_g2_irq_free(chip);
> +		mutex_lock(&chip->reg_lock);
>  		mv88e6xxx_g1_irq_free(chip);
> +		mutex_unlock(&chip->reg_lock);

Isn't the irq_free code likely to have to sleep waiting for any
ISR to complete??

	David