Re: [Libvir] PATCH: Prevent zombie ssh tunnels

On Tue, Sep 11, 2007 at 12:59:59AM +0100, Daniel P. Berrange wrote: > I noticed that when using the SSH tunnel for the remote driver I ended up > with alot of zombie SSH processes. We simply forgot to waitpid() on the > child when a connection attempt failed, or when shutting down an open remote > connection. Attached is a possible patch Looks fine, like Rich maybe a bit of refactoring might be good. The only worries I have is the following scenario: - the ssh process dies - libvirt based application takes some time to notice it - the OS span a new process with the same PID after a PID rollabck (not completely unlikely since the ssh may have been started a long time ago) - we end-up killing a random process in the system I think this is mostly avoidable by resetting priv->pid to -1 or 0 on any child communication error, and before doing the kill in the patch. Even better would be to be able to check that the process corresponding to priv->pid is still a child of the current process, I wonder if this can be achieved without blocking with an initial waitpid()