MFC r257531:

Do not exit with error status after printing data for perftest.

Sponsored by:	Intel
MFC r257534:

Create a unique unit number for each controller and namespace cdev.

Sponsored by:	Intel
MFC 253656: Enhance the description of NOTE_TRACK:
- NOTE_TRACK has never triggered a NOTE_TRACK event from the parent pid.
  If NOTE_FORK is set, the listener will get a NOTE_FORK event from
  the parent pid, but not a separate NOTE_TRACK event.
- Explicitly note that the event added to monitor the child process
  preserves the fflags from the original event.
- Move the description of NOTE_TRACKERR under NOTE_TRACK as it is not a
  bit for the user to set (which is what this list pupports to be).
  Also, explicitly note that if an error occurs, the NOTE_CHILD event
  will not be generated.
MFC r257539:

When zero'ing out a buffer, make sure we are using right size.

Without this change, in the worst but unlikely case scenario, certain
administrative operations, including change of configuration, set or
delete key from a GEOM ELI provider, may leave potentially sensitive
information in buffer allocated from kernel memory.

We believe that it is not possible to actively exploit these issues, nor
does it impact the security of normal usage of GEOM ELI providers when
these operations are not performed after system boot.

Security:	possible sensitive information disclosure
Submitted by:	Clement Lecigne <clecigne google com>
MFC r256169 (by jimharris):
Fix the LINT build.
MFC 254072:
Don't emit a spurious EVFILT_PROC event with no fflags set on process exit
if NOTE_EXIT is not being monitored.  The rationale is that a listener
should only get an event for exit() if they registered interest via
NOTE_EXIT.  This matches the behavior on OS X.
- Don't save the exit status on process exit unless NOTE_EXIT is being
  monitored.
- Add an internal EV_DROP flag that requests kqueue_scan() to free the
  knote without signalling it to userland and use this when a process
  exits but the fflags in the knote is zero.
Merge r227738, r228574:
  Fill in sin_family in ioctl() arguments.
MFC 254287: Some small cleanups to the fixes in r180340:
- Set NOTE_TRACKERR before running filt_proc().  If the knote did not
  have NOTE_FORK set in fflags when registered, then the TRACKERR event
  could miss being posted.
- Don't pass the pid in to filt_proc() for NOTE_FORK events.  The special
  handling for pids is done knote_fork() directly and no longer in
  filt_proc().
Merge remote-tracking branch 'upstream/stable/9' into stable/9