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From: "Serge E. Hallyn" <serge.hallyn-Z7WLFzj8eWMS+FvcfC7Uqw@public.gmane.org>
To: Rob Landley <rlandley-bzQdu9zFT3WakBO8gow8eQ@public.gmane.org>
Cc: "containers-cunTk1MwBs9QetFLy7KEm3xJsTq8ys+cHZ5vskTnxNA@public.gmane.org"
	<containers-cunTk1MwBs9QetFLy7KEm3xJsTq8ys+cHZ5vskTnxNA@public.gmane.org>
Subject: Re: Containers HOWTO?  (Where do I start?)
Date: Wed, 8 Dec 2010 16:11:43 -0600	[thread overview]
Message-ID: <20101208221143.GA7952@hallyn.com> (raw)
In-Reply-To: <7E28E74ACE78074AAD1BDD3E455CF874942D-w6YtkvcGFufufkSEj+1U85Z3qXmFLfmx@public.gmane.org>

Quoting Rob Landley (rlandley-bzQdu9zFT3WakBO8gow8eQ@public.gmane.org):
> But how does pivot_root enter into this when you haven't got an initrd to
> free?  I thought when you killed a container's init process that killed all

But pivot_root isn't just for initrd.  At this point I think both
libvirt-lxc and lxc.sf.net use pivot_root in favor of chroot for
creating containers.  Of course there are some stringent rules about the
pre-existing old (put) and new roots regarding sharing - you can best
see those in fs/namespace.c:pivot_root, i don't know that they're well
documented anywhere.

> the children and freed the resources, so how does pivot_root enter
> into this?  (You don't reparent existing processes, you span new ones,
> right?)

Right.  And you do the pivot_root only for the container, not the
whole system.  Sorry, I'm missing something about what you're saying
about killing the container.

-serge

      parent reply	other threads:[~2010-12-08 22:11 UTC|newest]

Thread overview: 4+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2010-12-08  8:36 Containers HOWTO? (Where do I start?) Rob Landley
     [not found] ` <7E28E74ACE78074AAD1BDD3E455CF87493D3-w6YtkvcGFufufkSEj+1U85Z3qXmFLfmx@public.gmane.org>
2010-12-08 15:02   ` Serge E. Hallyn
     [not found]     ` <20101208150239.GC8316-A9i7LUbDfNHQT0dZR+AlfA@public.gmane.org>
2010-12-08 21:17       ` Rob Landley
     [not found]         ` <7E28E74ACE78074AAD1BDD3E455CF874942D-w6YtkvcGFufufkSEj+1U85Z3qXmFLfmx@public.gmane.org>
2010-12-08 22:11           ` Serge E. Hallyn [this message]

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