If the cpumanager feature gate is disabled, the corresponsing field
of the containerManager will be nil.
A couple functions don't check for this occurrence and happily
deference the pointer unconditionally, leading to possible segfaults.
The relevant functions were introduced to support the podresources API,
so to trigger this segfault all the following are needed:
- cpumanager feature gate has to be disabled explicitely
- any podresources API must be called
Worth pointing out that when the new functions were introduced (around
kubernetes 1.20) the default feature gate for cpumanager was already set
to true, hence this bug is expected to be triggered rarely.
Signed-off-by: Francesco Romani <fromani@redhat.com>
Update dependencies and the test images to use pause 3.5. We also
provide a changelog entry for the new container image version.
Signed-off-by: Sascha Grunert <sgrunert@redhat.com>
Commit cc50aa9dfb introduced GetResourceStats, a method which collected
all the statistics from various cgroup controllers, only to discard all
of the info collected except a single value (memory usage).
While one may argue that this method can potentially be used from other
places, this did not happen since it was added 4+ years ago.
Let's streamline this code and only collect what we need, i.e. memory
usage. Rename the method accordingly.
While at it, fix pkg/kubelet/cm/cgroup_manager_unsupported.go to not
instantiate a new error every time a method is called.
Signed-off-by: Kir Kolyshkin <kolyshkin@gmail.com>
This was added by commit a9772b2290.
In the current codebase, the cgroup being updated was created using
runc/opencontainers' manager.Apply(), which already does controllers
propagation, so there is no need to repeat that on every update.
Signed-off-by: Kir Kolyshkin <kolyshkin@gmail.com>
FeatureGate acts as a secondary switch to disable cloud-controller loops
in KCM, Kubelet and KAPI.
Provide comprehensive logging information to users, so they will be
guided in adoption of out-of-tree cloud provider implementation.
Volumes that are provisioned with `VolumeMode: Block` often have a
MetrucsProvider interface declared in their type. However, the
MetricsProvider should implement a GetMetrics() function. In the cases
where the storage drivers do not implement GetMetrics(), a panic can
occur.
Usual type-assertions are not sufficient in this case. All assertions
assume the interface is present. There is no straight forward way to
verify that a valid GetMetrics() function is provided.
By adding SupportsMetrics(), storage driver implementations require
careful reviewing for metrics support.
