Re: [PATCH net] net: mdiobus: get rid of a BUG_ON()

[Russell King (Oracle)]

On Sat, May 15, 2021 at 01:01:11PM +0300, Dan Carpenter wrote:
> We spotted a bug recently during a review where a driver was
> unregistering a bus that wasn't registered, which would trigger this
> BUG_ON().  Let's handle that situation more gracefully, and just print
> a warning and return.
> 
> Reported-by: Russell King <linux@xxxxxxxxxxxxxxx>

This probably ought to be updated to:

Reported-by: Russell King (Oracle) <rmk+kernel@xxxxxxxxxxxxxxx>

now please.

> Signed-off-by: Dan Carpenter <dan.carpenter@xxxxxxxxxx>

Reviewed-by: Russell King (Oracle) <rmk+kernel@xxxxxxxxxxxxxxx>

> ---
>  drivers/net/phy/mdio_bus.c | 3 ++-
>  1 file changed, 2 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/net/phy/mdio_bus.c b/drivers/net/phy/mdio_bus.c
> index dadf75ff3ab9..6045ad3def12 100644
> --- a/drivers/net/phy/mdio_bus.c
> +++ b/drivers/net/phy/mdio_bus.c
> @@ -607,7 +607,8 @@ void mdiobus_unregister(struct mii_bus *bus)
>  	struct mdio_device *mdiodev;
>  	int i;
>  
> -	BUG_ON(bus->state != MDIOBUS_REGISTERED);
> +	if (WARN_ON_ONCE(bus->state != MDIOBUS_REGISTERED))
> +		return;
>  	bus->state = MDIOBUS_UNREGISTERED;
>  
>  	for (i = 0; i < PHY_MAX_ADDR; i++) {
> -- 
> 2.30.2
> 
> 

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