Jann Horn <jannh@xxxxxxxxxx> wrote: > + /* > + * Reject writing to watch queue pipes before the point where we lock > + * the pipe. > + * Otherwise, lockdep would be unhappy if the caller already has another > + * pipe locked. > + * If we had to support locking a normal pipe and a notification pipe at > + * the same time, we could set up lockdep annotations for that, but > + * since we don't actually need that, it's simpler to just bail here. > + */ > + if (pipe_has_watch_queue(pipe)) > + return -EXDEV; > + Linus wanted it to be possible for the user to write to a notificaiton pipe. David
