Re: [E1000-devel] False ethtool report on Link Detection

[Tantilov, E. S <emi...@in...>]

>-----Original Message-----
>From: Anand Raj Manickam [mailto:an...@gm...]
>Sent: Tuesday, March 26, 2013 5:04 AM
>To: Waskiewicz Jr, Peter P
>Cc: e10...@li...
>Subject: Re: [E1000-devel] False ethtool report on Link Detection
>
>On Tue, Mar 26, 2013 at 12:09 PM, Waskiewicz Jr, Peter P
><pet...@in...> wrote:
>> On 3/25/2013 10:56 PM, Anand Raj Manickam wrote:
>>>
>>> I m using the e1000e driver for Intel 82574L chipset .
>>> When the cable is plugged in and Auto Negotiated , It reports as Link
>>> Detected as NO. I need to do a ifconfig up eth3 to get the Link
>>> Detected as YES .

This is the correct behavior. The Link status in this case is reported by ethtool, not the driver:

Look in net/core/ethtool.c in your kernel source:

u32 ethtool_op_get_link(struct net_device *dev)
{
	return netif_carrier_ok(dev) ? 1 : 0;

This behavior should be consistent across all drivers that provide this info. From what I can see struct ethtool_cmd which carries this information does not have a link member.

Thanks,
Emil