netns compilation

[Eric W. Biederman]

Pavel Emelyanov <xemul at openvz.org> writes:

> Daniel Lezcano wrote:
>> Actually the CONFIG_NET_NS is depending on CONFIG_NET and !CONFIG_SYSFS
>> 
>> In order to disable CONFIG_SYSFS, I must specify CONFIG_EMBEDDED to have 
>> the choice to unset the sysfs.
>> 
>> Why don't we make CONFIG_NET_NS depends on CONFIG_NET and 
>> CONFIG_SYSFS_DEPRECATED ?
>> 
>
> AFAIK the SYSFS_DEPRECATED hides the sysfs functionality (files)
> that is not recommended to use, but doesn't disable the sysfs
> filesystem as is. On the other hand the NET_NS doesn't require 
> any deprecated sysfs files, it just can't work at all with the 
> SYSFS turned on. 
>
> That's why the things look like this.

Exactly.  Once we get the sysfs support merged this restriction will go away
but until then attempting to register a two copies of the loopback device
with sysfs is fatal.

Eric