func (s *DockerSuite) TestUpdateKernelMemoryUninitialized(c *check.C) {
	testRequires(c, DaemonIsLinux, kernelMemorySupport)

	isNewKernel := kernel.CheckKernelVersion(4, 6, 0)
	name := "test-update-container"
	dockerCmd(c, "run", "-d", "--name", name, "busybox", "top")
	_, _, err := dockerCmdWithError("update", "--kernel-memory", "100M", name)
	// Update kernel memory to a running container without kernel memory initialized
	// is not allowed before kernel version 4.6.
	if !isNewKernel {
		c.Assert(err, check.NotNil)
	} else {
		c.Assert(err, check.IsNil)
	}

	dockerCmd(c, "pause", name)
	_, _, err = dockerCmdWithError("update", "--kernel-memory", "200M", name)
	if !isNewKernel {
		c.Assert(err, check.NotNil)
	} else {
		c.Assert(err, check.IsNil)
	}
	dockerCmd(c, "unpause", name)

	dockerCmd(c, "stop", name)
	dockerCmd(c, "update", "--kernel-memory", "300M", name)
	dockerCmd(c, "start", name)

	c.Assert(inspectField(c, name, "HostConfig.KernelMemory"), checker.Equals, "314572800")

	file := "/sys/fs/cgroup/memory/memory.kmem.limit_in_bytes"
	out, _ := dockerCmd(c, "exec", name, "cat", file)
	c.Assert(strings.TrimSpace(out), checker.Equals, "314572800")
}

func checkKernel() error {
	// Check for unsupported kernel versions
	// FIXME: it would be cleaner to not test for specific versions, but rather
	// test for specific functionalities.
	// Unfortunately we can't test for the feature "does not cause a kernel panic"
	// without actually causing a kernel panic, so we need this workaround until
	// the circumstances of pre-3.10 crashes are clearer.
	// For details see https://github.com/docker/docker/issues/407
	// Docker 1.11 and above doesn't actually run on kernels older than 3.4,
	// due to containerd-shim usage of PR_SET_CHILD_SUBREAPER (introduced in 3.4).
	if !kernel.CheckKernelVersion(3, 10, 0) {
		v, _ := kernel.GetKernelVersion()
		if os.Getenv("DOCKER_NOWARN_KERNEL_VERSION") == "" {
			logrus.Fatalf("Your Linux kernel version %s is not supported for running docker. Please upgrade your kernel to 3.10.0 or newer.", v.String())
		}
	}
	return nil
}

func verifyContainerResources(resources *containertypes.Resources, sysInfo *sysinfo.SysInfo, update bool) ([]string, error) {
	warnings := []string{}

	// memory subsystem checks and adjustments
	if resources.Memory != 0 && resources.Memory < linuxMinMemory {
		return warnings, fmt.Errorf("Minimum memory limit allowed is 4MB")
	}
	if resources.Memory > 0 && !sysInfo.MemoryLimit {
		warnings = append(warnings, "Your kernel does not support memory limit capabilities or the cgroup is not mounted. Limitation discarded.")
		logrus.Warn("Your kernel does not support memory limit capabilities or the cgroup is not mounted. Limitation discarded.")
		resources.Memory = 0
		resources.MemorySwap = -1
	}
	if resources.Memory > 0 && resources.MemorySwap != -1 && !sysInfo.SwapLimit {
		warnings = append(warnings, "Your kernel does not support swap limit capabilities or the cgroup is not mounted. Memory limited without swap.")
		logrus.Warn("Your kernel does not support swap limit capabilities,or the cgroup is not mounted. Memory limited without swap.")
		resources.MemorySwap = -1
	}
	if resources.Memory > 0 && resources.MemorySwap > 0 && resources.MemorySwap < resources.Memory {
		return warnings, fmt.Errorf("Minimum memoryswap limit should be larger than memory limit, see usage")
	}
	if resources.Memory == 0 && resources.MemorySwap > 0 && !update {
		return warnings, fmt.Errorf("You should always set the Memory limit when using Memoryswap limit, see usage")
	}
	if resources.MemorySwappiness != nil && *resources.MemorySwappiness != -1 && !sysInfo.MemorySwappiness {
		warnings = append(warnings, "Your kernel does not support memory swappiness capabilities or the cgroup is not mounted. Memory swappiness discarded.")
		logrus.Warn("Your kernel does not support memory swappiness capabilities, or the cgroup is not mounted. Memory swappiness discarded.")
		resources.MemorySwappiness = nil
	}
	if resources.MemorySwappiness != nil {
		swappiness := *resources.MemorySwappiness
		if swappiness < -1 || swappiness > 100 {
			return warnings, fmt.Errorf("Invalid value: %v, valid memory swappiness range is 0-100", swappiness)
		}
	}
	if resources.MemoryReservation > 0 && !sysInfo.MemoryReservation {
		warnings = append(warnings, "Your kernel does not support memory soft limit capabilities or the cgroup is not mounted. Limitation discarded.")
		logrus.Warn("Your kernel does not support memory soft limit capabilities or the cgroup is not mounted. Limitation discarded.")
		resources.MemoryReservation = 0
	}
	if resources.MemoryReservation > 0 && resources.MemoryReservation < linuxMinMemory {
		return warnings, fmt.Errorf("Minimum memory reservation allowed is 4MB")
	}
	if resources.Memory > 0 && resources.MemoryReservation > 0 && resources.Memory < resources.MemoryReservation {
		return warnings, fmt.Errorf("Minimum memory limit can not be less than memory reservation limit, see usage")
	}
	if resources.KernelMemory > 0 && !sysInfo.KernelMemory {
		warnings = append(warnings, "Your kernel does not support kernel memory limit capabilities or the cgroup is not mounted. Limitation discarded.")
		logrus.Warn("Your kernel does not support kernel memory limit capabilities or the cgroup is not mounted. Limitation discarded.")
		resources.KernelMemory = 0
	}
	if resources.KernelMemory > 0 && resources.KernelMemory < linuxMinMemory {
		return warnings, fmt.Errorf("Minimum kernel memory limit allowed is 4MB")
	}
	if resources.KernelMemory > 0 && !kernel.CheckKernelVersion(4, 0, 0) {
		warnings = append(warnings, "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.")
		logrus.Warn("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.")
	}
	if resources.OomKillDisable != nil && !sysInfo.OomKillDisable {
		// only produce warnings if the setting wasn't to *disable* the OOM Kill; no point
		// warning the caller if they already wanted the feature to be off
		if *resources.OomKillDisable {
			warnings = append(warnings, "Your kernel does not support OomKillDisable. OomKillDisable discarded.")
			logrus.Warn("Your kernel does not support OomKillDisable. OomKillDisable discarded.")
		}
		resources.OomKillDisable = nil
	}

	if resources.PidsLimit != 0 && !sysInfo.PidsLimit {
		warnings = append(warnings, "Your kernel does not support pids limit capabilities or the cgroup is not mounted. PIDs limit discarded.")
		logrus.Warn("Your kernel does not support pids limit capabilities or the cgroup is not mounted. PIDs limit discarded.")
		resources.PidsLimit = 0
	}

	// cpu subsystem checks and adjustments
	if resources.NanoCPUs > 0 && resources.CPUPeriod > 0 {
		return warnings, fmt.Errorf("Conflicting options: Nano CPUs and CPU Period cannot both be set")
	}
	if resources.NanoCPUs > 0 && resources.CPUQuota > 0 {
		return warnings, fmt.Errorf("Conflicting options: Nano CPUs and CPU Quota cannot both be set")
	}
	if resources.NanoCPUs > 0 && (!sysInfo.CPUCfsPeriod || !sysInfo.CPUCfsQuota) {
		return warnings, fmt.Errorf("NanoCPUs can not be set, as your kernel does not support CPU cfs period/quota or the cgroup is not mounted")
	}
	// The highest precision we could get on Linux is 0.001, by setting
	//   cpu.cfs_period_us=1000ms
	//   cpu.cfs_quota=1ms
	// See the following link for details:
	// https://www.kernel.org/doc/Documentation/scheduler/sched-bwc.txt
	// Here we don't set the lower limit and it is up to the underlying platform (e.g., Linux) to return an error.
	// The error message is 0.01 so that this is consistent with Windows
	if resources.NanoCPUs < 0 || resources.NanoCPUs > int64(sysinfo.NumCPU())*1e9 {
		return warnings, fmt.Errorf("Range of CPUs is from 0.01 to %d.00, as there are only %d CPUs available", sysinfo.NumCPU(), sysinfo.NumCPU())
	}

	if resources.CPUShares > 0 && !sysInfo.CPUShares {
		warnings = append(warnings, "Your kernel does not support CPU shares or the cgroup is not mounted. Shares discarded.")
		logrus.Warn("Your kernel does not support CPU shares or the cgroup is not mounted. Shares discarded.")
		resources.CPUShares = 0
	}
//.........这里部分代码省略.........