- Fixed a race condition that could result in erroneous volume unmounts for flex volume plugins during kubelet restart. ([#127669](https://github.com/kubernetes/kubernetes/pull/127669), [@olyazavr](https://github.com/olyazavr))

- Fixed attaching volumes after detach errors. Now volumes that failed to detach are not treated as attached. Kubernetes will make sure they are fully attached before they can be used by pods. ([#120595](https://github.com/kubernetes/kubernetes/pull/120595), [@jsafrane](https://github.com/jsafrane))...

- It introduces a new scope name `VolumeAttributesClass`. 
  
  It matches all PVC objects that have the volume attributes class mentioned. 
  

- Kubelet: Fix the volume manager didn't check the device mount state in the actual state of the world before marking the volume as detached. It may cause a pod to be stuck in the Terminating state due to the above issue when it was deleted. ([#129063](https://github.com/kubernetes/kubernetes/pull/129063), [@carlory](https...

 - Kubelet flag `--keep-terminated-pod-volumes` was removed.  This flag was deprecated in 2017. ([#122082](https://github.com/kubernetes/kubernetes/pull/122082), [@carlory](https://github.com/carlory)) [SIG Apps, Node, Storage and Testing]
 
## Changes by Kind

### Deprecation

- Enabled kube-apiserver support for `PodCertificateRequest` and `PodCertificate` projected volumes (behind the `PodCertificateRequest` feature gate). ([#128010](https://github.com/kubernetes/kubernetes/pull/128010), [@ahmedtd](https://github.com/ahmedtd)) [SIG API Machinery, Apps, Auth, Cloud Provider, Etcd, Node, Storage and Testing]

    Map<R, Map<C, V>> rows = new LinkedHashMap<>();
    for (R row : rowSpace) {
      rows.put(row, new LinkedHashMap<C, V>());
    }
    Map<C, Map<R, V>> columns = new LinkedHashMap<>();
    for (C col : columnSpace) {
      columns.put(col, new LinkedHashMap<R, V>());
    }
    int[] cellRowIndices = new int[cellList.size()];
    int[] cellColumnInRowIndices = new int[cellList.size()];

      return super.put(key, value);
    }
  }

  /** Overridden column iterator to return columns values in globally sorted order. */
  @Override
  Iterator<C> createColumnKeyIterator() {
    Comparator<? super C> comparator = columnComparator();

    Iterator<C> merged =
        mergeSorted(
            transform(backingMap.values(), (Map<C, V> input) -> input.keySet().iterator()),
            comparator);

      return super.put(key, value);
    }
  }

  /** Overridden column iterator to return columns values in globally sorted order. */
  @Override
  Iterator<C> createColumnKeyIterator() {
    Comparator<? super C> comparator = columnComparator();

    Iterator<C> merged =
        mergeSorted(
            transform(backingMap.values(), (Map<C, V> input) -> input.keySet().iterator()),
            comparator);

      /*
       * This sorting logic leads to a cellSet() ordering that may not be expected and that isn't
       * documented in the Javadoc. If a row Comparator is provided, cellSet() iterates across the
       * columns in the first row, the columns in the second row, etc. If a column Comparator is
       * provided but a row Comparator isn't, cellSet() iterates across the rows in the first
       * column, the rows in the second column, etc.
       */