Public bug reported:
[Impact]
On hibernation xen-netfront is setting the device state on the xenbus to
"Closing" and then it's waiting for the backend state to acknowledge
that state (with a timeout). However, if the device is already in the
state "Closed" this opteration will always hit the timeout, preventing
the system to hibernate correctly.
[Test case]
It is a quite rare condition that can be reproduced hibernating/resuming
a Xen instance multiple times. When the problem happens we should in the
log a Xen error message like the following:
Freezing timed out; the device may become inconsistent state
[Fix]
If the device is already in the state "Closed", simply tear it down
without notifying the Xen backend.
[Regression potential]
The fix would just prevent aborting hibernation if the netfront device
is already in a "Closed" state. The resume callback is forcing the
device into the "Initializing" state anyway, basically forcing a reset
of the device, so nothing else in the state machine can be potentially
broken.
** Affects: linux-aws (Ubuntu)
Importance: Undecided
Status: New
** Affects: linux-aws (Ubuntu Focal)
Importance: Undecided
Status: New
** Affects: linux-aws (Ubuntu Groovy)
Importance: Undecided
Status: New
** Also affects: linux-aws (Ubuntu Focal)
Importance: Undecided
Status: New
** Also affects: linux-aws (Ubuntu Groovy)
Importance: Undecided
Status: New
** Summary changed:
- aws: xen-netfront: prevent potential deadlock on hibernate
+ aws: xen-netfront: prevent potential error on hibernate
** Summary changed:
- aws: xen-netfront: prevent potential error on hibernate
+ aws: xen-netfront: potential error on hibernate
** Summary changed:
- aws: xen-netfront: potential error on hibernate
+ aws: xen-netfront: prevent potential error on hibernate
--
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/1906850
Title:
aws: xen-netfront: prevent potential error on hibernate
Status in linux-aws package in Ubuntu:
New
Status in linux-aws source package in Focal:
New
Status in linux-aws source package in Groovy:
New
Bug description:
[Impact]
On hibernation xen-netfront is setting the device state on the xenbus
to "Closing" and then it's waiting for the backend state to
acknowledge that state (with a timeout). However, if the device is
already in the state "Closed" this opteration will always hit the
timeout, preventing the system to hibernate correctly.
[Test case]
It is a quite rare condition that can be reproduced
hibernating/resuming a Xen instance multiple times. When the problem
happens we should in the log a Xen error message like the following:
Freezing timed out; the device may become inconsistent state
[Fix]
If the device is already in the state "Closed", simply tear it down
without notifying the Xen backend.
[Regression potential]
The fix would just prevent aborting hibernation if the netfront device
is already in a "Closed" state. The resume callback is forcing the
device into the "Initializing" state anyway, basically forcing a reset
of the device, so nothing else in the state machine can be potentially
broken.
To manage notifications about this bug go to:
https://bugs.launchpad.net/ubuntu/+source/linux-aws/+bug/1906850/+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
