On 11/30, Eric W. Biederman wrote: > > 2) I keep thinking zap_pid_ns_processes() should be changed so that > after it sends SIGKILL to all of the relevant processes to not wait, At least I think it should not wait for the tasks injected into this ns. Because this looks like a kernel bug even if we forget about this deadlock. Say we create a task P using clone(CLONE_NEWPID), then inject a task T into P's pid-namespace via setns/fork. This make the process P "unkillable", it will hang in zap_pid_ns_processes() "forever" until T->parent reaps a zombie task T killed by P. Oleg.
