when we upgrade the k8s from 1.6.4 to 1.9.0, after a few days, the product environment report the machine is hang and jvm crash in container randomly , we found the cgroup memory css id is not release, when cgroup css id is large than 65535, the machine is hang, we must restart the machine.

we had found runc/libcontainers/memory.go in k8s 1.9.0 had delete the if condition, which cause the kernel memory open by default, but we are using kernel 3.10.0-514.16.1.el7.x86_64, on this version, kernel memory limit is not stable, which leak the cgroup memory leak and application crash randomly

when we run "docker run -d --name test001 --kernel-memory 100M " , docker report
WARNING: You specified a kernel memory limit on a kernel older than 4.0. Kernel memory limits are experimental on older kernels, it won't work as expected and can cause your system to be unstable.

k8s.io/kubernetes/vendor/github.com/opencontainers/runc/libcontainer/cgroups/fs/memory.go

-		if d.config.KernelMemory != 0 {
+			// Only enable kernel memory accouting when this cgroup
+			// is created by libcontainer, otherwise we might get
+			// error when people use `cgroupsPath` to join an existed
+			// cgroup whose kernel memory is not initialized.
 			if err := EnableKernelMemoryAccounting(path); err != nil {
 				return err
 			}

I want to know why kernel memory open by default? can k8s consider the different kernel version?

Is this a BUG REPORT or FEATURE REQUEST?: BUG REPORT

Uncomment only one, leave it on its own line:

/kind bug
/kind feature

What happened:
application crash and cgroup memory leak

What you expected to happen:
application stable and cgroup memory doesn't leak

How to reproduce it (as minimally and precisely as possible):
install k8s 1.9.x on kernel 3.10.0-514.16.1.el7.x86_64 machine, and create and delete pod repeatedly, when create more than 65535/3 times , the kubelet report "cgroup no space left on device" error, when the cluster run a few days , the container will crash.

Anything else we need to know?:

Environment: kernel 3.10.0-514.16.1.el7.x86_64

• Kubernetes version (use kubectl version): k8s 1.9.x
• Cloud provider or hardware configuration:
• OS (e.g. from /etc/os-release):

NAME="CentOS Linux"
VERSION="7 (Core)"
ID="centos"
ID_LIKE="rhel fedora"
VERSION_ID="7"
PRETTY_NAME="CentOS Linux 7 (Core)"
ANSI_COLOR="0;31"
CPE_NAME="cpe:/o:centos:centos:7"
HOME_URL="https://www.centos.org/"
BUG_REPORT_URL="https://bugs.centos.org/"

CENTOS_MANTISBT_PROJECT="CentOS-7"
CENTOS_MANTISBT_PROJECT_VERSION="7"
REDHAT_SUPPORT_PRODUCT="centos"
REDHAT_SUPPORT_PRODUCT_VERSION="7"

• Kernel (e.g. uname -a): 3.10.0-514.16.1.el7.x86_64
• Install tools: rpm
• Others: