Re: [RFC PATCH] fs: call_usermodehelper_root helper introduced

[Stanislav Kinsbursky <skinsbursky@parallels.com>]

22.05.2013 22:35, Eric W. Biederman пишет:
> ebiederm@xmission.com (Eric W. Biederman) writes:
>
>> I am missing a lot of context here and capturing the context of a
>> process at time time we mount the filesystem and reconstituing it in
>> call user mode helper seems like something we could do.
>
> If we want to do something like this the only sane thing I can see is to
> have a per container version of kthread call it uthread.  That the user
> mode helper code would use to launch a new process.
>

The main point here, is that a container can have it's own root, different
to kthread's one (another mount or at least chroot result).

> Anything else and I expect we will be tearing our hair out for the rest
> of our lives with weird corner cases or unexpected semantics.
>
> At first glace I would exepct uthread to be per pid namespace in
> implementation.
>

Having a per-pidnamespace kernel thread would be really great.
But regrettably doesn't solve the root swapping problem.

> Eric
>
>


-- 
Best regards,
Stanislav Kinsbursky