Re: cdc_ncm doesn't detect link unless ethtool is run (ASIX AX88179B)

[Oliver Neukum <oneukum@suse.com>]

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On 15.11.25 09:58, WGH wrote:
> Hello.
> 
> I'm running Linux 6.17.7, and recently obtained a UGREEN 6 in 1 hub containing an AX88179B chip.
> 
> By default, it uses the generic cdc_ncm driver, and it works mostly okay.
> 
> The annoying problem I have is that most of the time the kernel doesn't notice that the link is up. ip link reports NO-CARRIER, network management daemon doesn't configure the interface, and so on.

Hi,

that strongly points to a race condition.
Could you try the attached diagnostic patch?

	Regards
		Oliver

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diff --git a/drivers/net/usb/usbnet.c b/drivers/net/usb/usbnet.c
index 1d9faa70ba3b..d042ba574217 100644
--- a/drivers/net/usb/usbnet.c
+++ b/drivers/net/usb/usbnet.c
@@ -1892,7 +1892,7 @@ usbnet_probe(struct usb_interface *udev, const struct usb_device_id *prod)
 
 	netif_device_attach(net);
 
-	if (dev->driver_info->flags & FLAG_LINK_INTR)
+	//if (dev->driver_info->flags & FLAG_LINK_INTR)
 		usbnet_link_change(dev, 0, 0);
 
 	return 0;