[libvirt] [PATCHv2 6/7] lxc: add virProcessRunInMountNamespace

[Guido Günther]

On Wed, Jan 08, 2014 at 12:26:41PM -0700, Eric Blake wrote:
> On 01/08/2014 12:10 PM, Guido Günther wrote:
> > On Mon, Dec 23, 2013 at 10:55:50PM -0700, Eric Blake wrote:
> > [..snip..] 
> >> +    if (virAsprintf(&path, "/proc/%llu/ns/mnt", (unsigned long long)pid) < 0)
> >> +        goto cleanup;
> >> +
> >> +    if ((fd = open(path, O_RDONLY)) < 0) {
> >> +        virReportSystemError(errno, "%s",
> >> +                             _("Kernel does not provide mount namespace"));
> >> +        goto cleanup;
> >> +    }
> > 
> > So in case mount namespaces are unavailable we'll fail these operations
> > entirely? I think this is the right thing to do but it will break
> > distros that have a too old kernel. So shutting down of containers will
> > no longer work (as it did before).
> 
> We'll fail the attempt to use initctl as the shutdown mechanism, but
> should still gracefully fall back to the attempt to use signals (once
> this patch is in [1]).  Or, if the user explicitly requested intictl
> only, then they WANT to know that initctl didn't work.

Ahh...the signals. Forgat that we have this too. Thanks!
 -- Guido