Public bug reported:

The following 25Gb Broadcom NIC error was seen on Xenial
running the 4.4.0-141-generic kernel on an amd64 host
seeing moderate-heavy network traffic (just once):

* The bnxt_en_po driver froze on a "TX timed out" error
  and triggered the Netdev Watchdog timer under load. 

* From kernel log:
  "NETDEV WATCHDOG: eno2d1 (bnxt_en_bpo): transmit queue 0 timed out"
  See attached kern.log excerpt file for full excerpt of error log.

* Release = Xenial 
  Kernel = 4.4.0-141-generic #167
  eno2d1 = Product Name: Broadcom Adv. Dual 25Gb Ethernet
  
* This caused the driver to reset in order to recover:
  
  "bnxt_en_bpo 0000:19:00.1 eno2d1: TX timeout detected, starting reset task!"
 
  driver: bnxt_en_bpo
  version: 1.8.1
  source: ubuntu/bnxt/bnxt.c: bnxt_tx_timeout()

* The loss of connectivity and softirq stall caused other failures
  on the system. 

* The bnxt_en_po driver is the imported Broadcom driver
  pulled in to support newer Broadcom HW (specific boards)
  while the bnx_en module continues to support the older
  HW. The current Linux upstream driver does not compile
  easily with the 4.4 kernel (too many changes). 

* This upstream and bnxt_en driver fix is a likely solution:
   "bnxt_en: Fix TX timeout during netpoll"
   commit: 73f21c653f930f438d53eed29b5e4c65c8a0f906
  
  This fix has not been applied to the bnxt_en_po driver
  version, but review of the code indicates that it is 
  susceptible to the bug, and the fix would be reasonable. 

* No easy way to reproduce this

** Affects: linux (Ubuntu)
     Importance: High
         Status: New


** Tags: xenial

-- 
You received this bug notification because you are a member of Ubuntu
Bugs, which is subscribed to Ubuntu.
https://bugs.launchpad.net/bugs/1814095

Title:
  bnxt_en_po: TX timed out triggering Netdev Watchdog Timer

To manage notifications about this bug go to:
https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1814095/+subscriptions

-- 
ubuntu-bugs mailing list
ubuntu-bugs@lists.ubuntu.com
https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs

Reply via email to