8634 epoll fails to wake on certain edge-triggered conditions
8635 epoll should not emit POLLNVAL
8636 recursive epoll should emit EPOLLRDNORM
Reviewed by: Jerry Jelinek <jerry.jelinek@joyent.com>
Reviewed by: Robert Mustacchi <rm@joyent.com>
Reviewed by: Toomas Soome <tsoome@me.com>
Reviewed by: Igor Kozhukhov <igor@dilos.org>

*** 18,27 ****
--- 18,29 ----
   *
   * CDDL HEADER END
   *
   * Copyright 2009 Sun Microsystems, Inc.  All rights reserved.
   * Use is subject to license terms.
+  *
+  * Copyright 2017 Joyent, Inc.
   */
  
  
  /*
   * Random number generator pseudo-driver
*** 327,337 ****
  
                  /*
                   * A non NULL pollhead pointer should be returned in case
                   * user polls for 0 events.
                   */
!                 if (*reventsp == 0 && !anyyet)
                          *phpp = &urnd_pollhd;
  
                  break;
          case DEVRANDOM:
                  kcf_rnd_chpoll(events, anyyet, reventsp, phpp);
--- 329,339 ----
  
                  /*
                   * A non NULL pollhead pointer should be returned in case
                   * user polls for 0 events.
                   */
!                 if ((*reventsp == 0 && !anyyet) || (events & POLLET))
                          *phpp = &urnd_pollhd;
  
                  break;
          case DEVRANDOM:
                  kcf_rnd_chpoll(events, anyyet, reventsp, phpp);