# Re: \[PATCH 2/4\] clone.2: Describe the user namespace

- From: Eric W. Biederman \<hidden\>
- Date: 2013-01-01 09:39:43 
- List: linux-api
- Page: https://ratatoskr.run/linux-api/2013/01/13328888
- Thread: https://ratatoskr.run/linux-api/2013/01/13328888/t.md

```text
"Michael Kerrisk (man-pages)" [ref] writes:

> Hi Eric,
>
> On Thu, Dec 27, 2012 at 6:47 PM, Eric W. Biederman
> [ref] wrote:
>>
>> There is one other bit that needs to be documented in clone, although
>> I am not certain where/how.
>>
>> The sequences:
>>
>> unshare(CLONE_NEWPID).
>> clone(CLONE_VM)
>>
>> setns(fd, CLONE_NEWPID).
>> clone(CLONE_VM).
>>
>> Now fail.
>
> Can you define "now" please. Which kernel version?

3.8

The sequence was impossible in 3.7.

I think that change that made that impossible happened in the 3.8-rc1 to
3.8-rc2 window.

Eric
```