Have you gone back and forth between the kernels? What is on the other end of 
the link? Have you checked your cabling?

If you're from Arista, I'd suggest filing this through more formal means 
(through your factory contacts) so this can be tracked more carefully.

Thanks.

Todd Fujinaka
Software Application Engineer
Networking Division (ND)
Intel Corporation
[email protected]
(503) 712-4565

-----Original Message-----
From: Wei Hu [mailto:[email protected]] 
Sent: Monday, July 21, 2014 12:51 AM
To: [email protected]
Subject: [E1000-devel] Difference in auto-negotiation behavior between 2.6.38 
kernel and 3.4.43 kernel

Hi All,

I have a system with an Intel 82575 family Ethernet adapter. The 
auto-negotiated speed changed after upgrading the kernel, with everything else 
intact.

With 2.6.38 kernel when the interface is up I would see this line from kernel:
igb: eth0 NIC Link is Up 100 Mbps Full Duplex, Flow Control: RX While with 
3.4.43 kernel I would see this instead:
igb: eth0 NIC Link is Up 10 Mbps Half Duplex, Flow Control: None

I'm wondering what kernel change could have caused this? I'd rather make a 
patch that reverts this change. Is it something in igb driver or is it in 
another layer? Has anyone else seen this? I appreciate any pointers! Please 
also see the ethtool output below.

2.6.38 ethtool output:
Supported ports: [ TP ]
Supported link modes:   10baseT/Half 10baseT/Full
                        100baseT/Half 100baseT/Full
                        1000baseT/Full
Supports auto-negotiation: Yes
Advertised link modes:  10baseT/Half 10baseT/Full
                        100baseT/Half 100baseT/Full
                        1000baseT/Full
Advertised pause frame use: No
Advertised auto-negotiation: Yes
Speed: 100Mb/s
Duplex: Full
Port: Twisted Pair
PHYAD: 1
Transceiver: internal
Auto-negotiation: on
MDI-X: Unknown
Supports Wake-on: pumbg
Wake-on: g
Current message level: 0x00002003 (8195)
       drv probe hw
Link detected: yes

3.4.43 ethtool output:
Supported ports: [ TP ]
Supported link modes:   10baseT/Half 10baseT/Full
                        100baseT/Half 100baseT/Full
                        1000baseT/Full
Supports auto-negotiation: Yes
Advertised link modes:  10baseT/Half 10baseT/Full
                        100baseT/Half 100baseT/Full
                        1000baseT/Full
Advertised pause frame use: Symmetric
Advertised auto-negotiation: Yes
Speed: 10Mb/s
Duplex: Half
Port: Twisted Pair
PHYAD: 1
Transceiver: internal
Auto-negotiation: on
MDI-X: Unknown
Supports Wake-on: pumbg
Wake-on: g
Current message level: 0x00002007 (8199)
       drv probe link hw
Link detected: yes

------------------------------------------------------------------------------
Want fast and easy access to all the code in your enterprise? Index and search 
up to 200,000 lines of code with a free copy of Black Duck Code Sight - the 
same software that powers the world's largest code search on Ohloh, the Black 
Duck Open Hub! Try it now.
http://p.sf.net/sfu/bds
_______________________________________________
E1000-devel mailing list
[email protected]
https://lists.sourceforge.net/lists/listinfo/e1000-devel
To learn more about Intel® Ethernet, visit 
http://communities.intel.com/community/wired

------------------------------------------------------------------------------
Want fast and easy access to all the code in your enterprise? Index and
search up to 200,000 lines of code with a free copy of Black Duck
Code Sight - the same software that powers the world's largest code
search on Ohloh, the Black Duck Open Hub! Try it now.
http://p.sf.net/sfu/bds
_______________________________________________
E1000-devel mailing list
[email protected]
https://lists.sourceforge.net/lists/listinfo/e1000-devel
To learn more about Intel® Ethernet, visit 
http://communities.intel.com/community/wired

Reply via email to