Re: Testing lxc 0.6.5 in Fedora 13

[Oleg Nesterov <oleg@redhat.com>]

On 04/06, Matt Helsley wrote:
>
> On Mon, Apr 05, 2010 at 08:44:43PM -0700, Roland McGrath wrote:
>
> > tracehook_report_clone_complete() call is made when that task_struct is no
> > longer guaranteed to be valid.

Hmm. I missed this.

> Also, if utrace allows multiple tracers and they each
> exist in a different namespace then storing a pid nr isn't going to work.

Yes, but utrace is simple. ptrace_report_clone() does

	ctx->eventmsg = child->pid;

we should fix this line and that is all, afaics. Every tracer has a
separate "struct ptrace_context *ctx".

> So my hunch is, in the long run, we'll need to hold a reference there and
> drop it when the last tracer detaches

Without utrace only one tracer is possible.

So, I think we should either change do_fork() to get the right tracee_pid_nr,
or add get/put into do_fork() and change tracehooks as Roland suggested.

Oleg.