[systemd-devel] [PATCH] Add the CPU hotplug rule

[Kay Sievers]

On Tue, Sep 2, 2014 at 5:22 AM, Zhenzhong Duan
<zhenzhong.duan at oracle.com> wrote:
> Cpu doesn't get online automaticly after hotplug when we test guest cpu
> add/remove in xen env.
>
> I don't have an baremetal env to test this, but I think it's same.
>
> The rule is missed in systemd but exist in legacy udev.

Udev is not a mechanism to establish an unconditional loop from the
kernel back to the kernel. Such rule makes no sense and we never
shipped that and will not ship it upstream now.

If a device should be unconditionally change its state, the kernel
should just do that on its own, and not rely on userspace to do that.

Kay