[BUG] tg3 network interface unstable

tg3 network interface unstable

Issue:

• Problems with tg3 network link going up/down over and over and over again before finally becoming ready.
• System taking a long time to reboot and having communication issues.
• Repeating errors in dmesg and /var/log/messages

  kernel: tg3 0000:03:06.0: firmware: requesting tigon/tg3_tso.bin
  kernel: ADDRCONF(NETDEV_UP): eth0: link is not ready
  kernel: tg3 0000:03:06.0: eth0: DMA Status error.  Resetting chip.
  kernel: tg3 0000:03:06.0: eth0: 0x00000000: 0x164814e4, 0x22b00146,\
   0x02000010, 0x00804010
  .. Multiple Lines of Register Dump ..
  kernel: tg3 0000:03:06.0: eth0: 0x00007010: 0x44ea66f0, 0x00014a00\
  , 0x009f0020, 0xa184a053
  kernel: tg3 0000:03:06.0: eth0: 0: Host status block \
  [00000007:00000001:(0000:0000:0000):(0000:0000)]
  kernel: tg3 0000:03:06.0: eth0: 0: NAPI info \
  [00000000:00000001:(0000:0000:01ff):0000:(00c8:0000:0000:0000)]
  kernel: tg3 0000:03:06.0: eth0: Link is up at 1000 Mbps, full duplex
  kernel: tg3 0000:03:06.0: eth0: Flow control is on for TX and on for RX
  kernel: tg3 0000:03:06.0: tg3_stop_block timed out, ofs=4800 enable_bit=2
  kernel: tg3 0000:03:06.0: eth0: Link is down
             

Environment:

• Red Hat Enterprise Linux 6.2 - kernel-2.6.32-220.4.1
• Red Hat Enterprise Linux 5.8 - kernel 2.6.18-308.1.1.el5

Resolution:

• RHEL 5 Update 8 Errata RHSA-2012-1174
• RHEL 6 Update 3 Errata RHSA-2012-0862

Root Cause:

Certain Broadcom devices, mostly the BMC5704 controllers, failed to work due to incorrect TSO (TCP Segmentation Offload) handling in the tg3 driver. The TSO handling code has been revised so that the devices now work as expected.