We masked off SIGCHLD in wait_on_helpers_zombies(), but in fact this is too
late: zombies can die any time after CR_STATE_RESTORE before this function
is called, which lead to us getting "unexpected" deaths. Instead, we should
mask off SIGCHLD before the helpers finish CR_STATE_RESTORE, since they're
explicitly going to wait on all their kids to make sure they don't die
anyway.
Signed-off-by: Tycho Andersen <tycho.andersen@canonical.com>
Acked-by: Andrew Vagin <avagin@virtuozzo.com>
Signed-off-by: Pavel Emelyanov <xemul@virtuozzo.com>