Re: [PATCH] net: usb: asix: avoid to call phylink_stop() a second time

[Andrew Lunn <andrew@lunn.ch>]

On Wed, Aug 06, 2025 at 04:30:17PM +0800, Xu Yang wrote:
> The kernel will have below dump when system resume if the USB net device
> was already disconnected during system suspend.

By disconnected, you mean pulled out?

> It's because usb_resume_interface() will be skipped if the USB core found
> the USB device was already disconnected. In this case, asix_resume() will
> not be called anymore. So asix_suspend/resume() can't be balanced. When
> ax88772_stop() is called, the phy device was already stopped. To avoid
> calling phylink_stop() a second time, check whether usb net device is
> already in suspend state.
> 
> Fixes: e0bffe3e6894 ("net: asix: ax88772: migrate to phylink")
> Cc: stable@vger.kernel.org
> Signed-off-by: Xu Yang <xu.yang_2@nxp.com>
> ---
>  drivers/net/usb/asix_devices.c | 3 ++-
>  1 file changed, 2 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/net/usb/asix_devices.c b/drivers/net/usb/asix_devices.c
> index 9b0318fb50b5..ac28f5fe7ac2 100644
> --- a/drivers/net/usb/asix_devices.c
> +++ b/drivers/net/usb/asix_devices.c
> @@ -932,7 +932,8 @@ static int ax88772_stop(struct usbnet *dev)
>  {
>  	struct asix_common_private *priv = dev->driver_priv;
>  
> -	phylink_stop(priv->phylink);
> +	if (!dev->suspend_count)
> +		phylink_stop(priv->phylink);

Looking at ax88172a.c, lan78xx.c and smsc95xx.c, they don't have
anything like this. Is asix special, or are all the others broken as
well?

	Andrew