Public bug reported:

The xen_netfront device is sometimes unresponsive after a hibernate and
resume event. This is limited to the c4, c5, m4, m5, r4, r5 instance
families, all of which are xen based, and support hibernation.

When the issue occurrs, the instance is inaccessible without a full
restart. Debugging by running a process which outputs regularly to the
serial console shows that the instance is still running.

A workaround is to build the xen_netfront module separately and restart
the module and networking during the resume handler. For example:

modprobe -r xen_netfront
modprobe xen_netfront
systemctl restart systemd-networkd

With this workaround in place, the unresponsive issue is no longer
observed.

To reproduce this problem:

1) Launch an c4, c5, m4, m5, r4, r5 instance type with a 5.0 or 5.3 kernel with 
on-demand hibernation support enabled.
2) Start a long-running process which generates messages to the serial console
3) Begin observing these messages on the console (using the AWS UI or CLI  to 
grab a screenshot).
4) Suspend and resume the instance, continuing to refresh the console 
screenshot.
5) The screenshot should continue to show updates even if ssh access is no 
longer working.

** Affects: linux-aws (Ubuntu)
     Importance: Undecided
         Status: New

** Description changed:

  The xen_netfront device is sometimes unresponsive after a hibernate and
  resume event. This is limited to the c4, c5, m4, m5, r4, r5 instance
  families, all of which are xen based, and support hibernation.
  
  When the issue occurrs, the instance is inaccessible without a full
  restart. Debugging by running a process which outputs regularly to the
  serial console shows that the instance is still running.
  
  A workaround is to build the xen_netfront module separately and restart
  the module and networking during the resume handler. For example:
  
  modprobe -r xen_netfront
  modprobe xen_netfront
  systemctl restart systemd-networkd
  
  With this workaround in place, the unresponsive issue is no longer
  observed.
+ 
+ To reproduce this problem:
+ 
+ 1) Launch an c4, c5, m4, m5, r4, r5 instance type with a 5.0 or 5.3 kernel 
with on-demand hibernation support enabled.
+ 2) Start a long-running process which generates messages to the serial console
+ 3) Begin observing these messages on the console (using the AWS UI or CLI  to 
grab a screenshot).
+ 4) Suspend and resume the instance, continuing to refresh the console 
screenshot.
+ 5) The screenshot should continue to show updates even if ssh access is no 
longer working.

-- 
You received this bug notification because you are a member of Kernel
Packages, which is subscribed to linux-aws in Ubuntu.
https://bugs.launchpad.net/bugs/1864041

Title:
  xen_netfront devices unresponsive after hibernation/resume

Status in linux-aws package in Ubuntu:
  New

Bug description:
  The xen_netfront device is sometimes unresponsive after a hibernate
  and resume event. This is limited to the c4, c5, m4, m5, r4, r5
  instance families, all of which are xen based, and support
  hibernation.

  When the issue occurrs, the instance is inaccessible without a full
  restart. Debugging by running a process which outputs regularly to the
  serial console shows that the instance is still running.

  A workaround is to build the xen_netfront module separately and
  restart the module and networking during the resume handler. For
  example:

  modprobe -r xen_netfront
  modprobe xen_netfront
  systemctl restart systemd-networkd

  With this workaround in place, the unresponsive issue is no longer
  observed.

  To reproduce this problem:

  1) Launch an c4, c5, m4, m5, r4, r5 instance type with a 5.0 or 5.3 kernel 
with on-demand hibernation support enabled.
  2) Start a long-running process which generates messages to the serial console
  3) Begin observing these messages on the console (using the AWS UI or CLI  to 
grab a screenshot).
  4) Suspend and resume the instance, continuing to refresh the console 
screenshot.
  5) The screenshot should continue to show updates even if ssh access is no 
longer working.

To manage notifications about this bug go to:
https://bugs.launchpad.net/ubuntu/+source/linux-aws/+bug/1864041/+subscriptions

-- 
Mailing list: https://launchpad.net/~kernel-packages
Post to     : kernel-packages@lists.launchpad.net
Unsubscribe : https://launchpad.net/~kernel-packages
More help   : https://help.launchpad.net/ListHelp

Reply via email to