Re: [libvirt] [PATCH 2/8] Add helper for running code in separate namespaces

Implement virProcessRunInMountNamespace, which runs callback of type virProcessNamespaceCallback in a container namespace. This uses a child process to run the callback, since you can't change the mount namespace of a thread. This implies that callbacks have to be careful about what code they run due to async safety rules. Idea by Dan Berrange, based on an initial report by Reco <recoverym4n(a)gmail.com&gt; at http://bugs.debian.org/cgi-bin/bugreport.cgi?bug=732394 Signed-off-by: Daniel Berrange <berrange(a)redhat.com&gt; Signed-off-by: Eric Blake <eblake(a)redhat.com&gt; --- src/libvirt_private.syms | 1 + src/util/virprocess.c | 107 +++++++++++++++++++++++++++++++++++++++++++++++ src/util/virprocess.h | 11 +++++ 3 files changed, 119 insertions(+)

+++ b/src/util/virprocess.c @@ -50,6 +50,8 @@ #include "virlog.h" #include "virutil.h" #include "virstring.h" +#include "virthread.h"

+ +/* Run cb(opaque) in the mount namespace of pid. Return -1 with error + * message raised if we fail to run the child, if the child dies from + * a signal, or if the child has status 1; otherwise return the exit + * status of the child.