onboard NIC not working after upgrade

[Dr. Michael J. Chudobiak]

Hi,

My onboard intel ethernet NIC (em1, e1000e driver) in my HP DC7800 no 
longer works after the upgrade to F21. It worked fine before. Inserting 
a PCI NIC (p3p1, e1000 driver) restores network functionality.

The link lights for the onboard NIC are on during the bios bootup, but 
go dark very early during the linux boot.

I don't really see anything interesting in the logs (I've grepped for 
e1000 below. Any suggestions? lshw says the onboard nic is "DISABLED". 
Why? ethtool says there is no link.

Debugging stuff:

[root at xena ~]# lshw -class network
   *-network DISABLED
        description: Ethernet interface
        product: 82566DM-2 Gigabit Network Connection
        vendor: Intel Corporation
        physical id: 19
        bus info: pci at 0000:00:19.0
        logical name: em1
        version: 02
        serial: 00:0f:fe:d4:f8:8e
        capacity: 1Gbit/s
        width: 32 bits
        clock: 33MHz
        capabilities: pm msi bus_master cap_list ethernet physical tp 
10bt 10bt-fd 100bt 100bt-fd 1000bt-fd autonegotiation
        configuration: autonegotiation=on broadcast=yes driver=e1000e 
driverversion=2.3.2-k firmware=1.3-1 latency=0 link=no multicast=yes 
port=twisted pair
        resources: irq:26 memory:f0200000-f021ffff 
memory:f0225000-f0225fff ioport:3100(size=32)
   *-network
        description: Ethernet interface
        product: 82541PI Gigabit Ethernet Controller
        vendor: Intel Corporation
        physical id: b
        bus info: pci at 0000:07:0b.0
        logical name: p3p1
        version: 05
        serial: 00:1b:21:20:07:6e
        size: 1Gbit/s
        capacity: 1Gbit/s
        width: 32 bits
        clock: 66MHz
        capabilities: pm pcix bus_master cap_list rom ethernet physical 
tp 10bt 10bt-fd 100bt 100bt-fd 1000bt-fd autonegotiation
        configuration: autonegotiation=on broadcast=yes driver=e1000 
driverversion=7.3.21-k8-NAPI duplex=full ip=192.168.0.94 latency=32 
link=yes mingnt=255 multicast=yes port=twisted pair speed=1Gbit/s
        resources: irq:22 memory:f0300000-f031ffff 
memory:f0320000-f033ffff ioport:2100(size=64) memory:f0340000-f035ffff



[root at xena ~]# ethtool em1
Settings for em1:
	Supported ports: [ TP ]
	Supported link modes:   10baseT/Half 10baseT/Full
	                        100baseT/Half 100baseT/Full
	                        1000baseT/Full
	Supported pause frame use: No
	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: Unknown!
	Duplex: Unknown! (255)
	Port: Twisted Pair
	PHYAD: 1
	Transceiver: internal
	Auto-negotiation: on
	MDI-X: Unknown (auto)
	Supports Wake-on: pumbg
	Wake-on: g
	Current message level: 0x00000007 (7)
			       drv probe link
	Link detected: no

[root at xena ~]# grep e1000 /var/log/messages


Jan  8 10:05:46 xena kernel: [    1.787026] e1000e: Intel(R) PRO/1000 
Network Driver - 2.3.2-k
Jan  8 10:05:46 xena kernel: [    1.787027] e1000e: Copyright(c) 1999 - 
2014 Intel Corporation.
Jan  8 10:05:46 xena kernel: [    1.787208] e1000e 0000:00:19.0: 
Interrupt Throttling Rate (ints/sec) set to dynamic conservative mode
Jan  8 10:05:46 xena kernel: [    2.088234] e1000e 0000:00:19.0 eth0: 
(PCI Express:2.5GT/s:Width x1) 00:0f:fe:d4:f8:8e
Jan  8 10:05:46 xena kernel: [    2.088237] e1000e 0000:00:19.0 eth0: 
Intel(R) PRO/1000 Network Connection
Jan  8 10:05:46 xena kernel: [    2.088257] e1000e 0000:00:19.0 eth0: 
MAC: 7, PHY: 6, PBA No: 1062FF-0FF
Jan  8 10:05:46 xena kernel: [    2.093634] e1000e 0000:00:19.0 em1: 
renamed from eth0
Jan  8 10:05:46 xena kernel: [   16.154347] e1000: Intel(R) PRO/1000 
Network Driver - version 7.3.21-k8-NAPI
Jan  8 10:05:46 xena kernel: [   16.154350] e1000: Copyright (c) 
1999-2006 Intel Corporation.
Jan  8 10:05:46 xena kernel: [   16.568865] e1000 0000:07:0b.0 eth0: 
(PCI:33MHz:32-bit) 00:1b:21:20:07:6e
Jan  8 10:05:46 xena kernel: [   16.568870] e1000 0000:07:0b.0 eth0: 
Intel(R) PRO/1000 Network Connection
Jan  8 10:05:46 xena kernel: [   17.008937] e1000 0000:07:0b.0 p3p1: 
renamed from eth0
Jan  8 10:05:48 xena kernel: [   21.061834] e1000: p3p1 NIC Link is Up 
1000 Mbps Full Duplex, Flow Control: RX/TX