@terryh-orcas,

if you are able to reproduce the problem relatively quickly and easily, then I 
suggest testing different kernel versions, up to the latest upstream, to see if 
and where it may be fixed with a newer i40e kernel driver.  You can get 
upstream kernel debs here:
http://kernel.ubuntu.com/~kernel-ppa/mainline/?C=N;O=D

If you can narrow down the kernel to a specific short range (i.e. kernel
X definitely fails, kernel Y never fails), I can review the upstream
i40e driver for specific changes to backport.

If you can't reproduce it easily/quickly, there is another method of
debug involving undocumented i40e register modification.  See bug
1723127 comment 10 for details.  If you try that method, you should
attempt it with the latest kernel you can reproduce the problem with.
As I don't have the chipset specifications, if you do reproduce it this
way and can isolate the problem to a specific register/bit, I'll have to
take that info back to Intel to ask them for clarification.  Also note
that there are 2 registers that you have to test each bit individually
for, so this method can take a very long time if it takes you a long
time to reproduce the problem.

Unfortunately, as has been mentioned in this and past bugs, the MDD
event is generated by the i40e firmware and there is no documented way
to tell what the i40e kernel driver did that the firmware didn't like
(assuming it was something the driver did, and not external or firmware
issues).  Intel does update their upstream i40e driver with fixes for
MDD firmware/driver bugs regularly, so this will likely only be fixed by
a patch coming from Intel upstream, that we need to backport to our
older stable Ubuntu kernel(s).

Sorry I can't help more.

-- 
You received this bug notification because you are a member of Ubuntu
Bugs, which is subscribed to Ubuntu.
https://bugs.launchpad.net/bugs/1772675

Title:
  Intel i40e PF reset due to incorrect MDD detection
  (continues...again...)

To manage notifications about this bug go to:
https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1772675/+subscriptions

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

Reply via email to