MFC r272730,273018:
  Add support for QAC AR816x/AR817x Gigabit/Fast Ethernet controllers.
  These controllers seem to have the same feature of AR813x/AR815x and
  improved RSS support(4 TX queues and 8 RX queues).  alc(4) supports
  all hardware features except RSS.  I didn't implement RX checksum
  offloading for AR816x/AR817x just because I couldn't get
  confirmation from the Vendor whether AR816x/AR817x corrected its
  predecessor's RX checksum offloading bug on fragmented packets.
  This change adds supports for the following controllers.
   o AR8161 PCIe Gigabit Ethernet controller
   o AR8162 PCIe Fast Ethernet controller
   o AR8171 PCIe Gigabit Ethernet controller
   o AR8172 PCIe Fast Ethernet controller
   o Killer E2200 Gigabit Ethernet controller

  Relnotes:	yes
MFC r272731:
  Document newly added controller AR816x/AR817x.
MFC r262294 (by ivoras):
Explain how and where kern.cam.ada.write_cache can be set in practical
situations.
MFC r262332 (by ivoras): Grammar fix
MFC r271926:  Mention read_ahead tunables/sysctls.
MFC r272683:
- Fix compile warning when compiling with GCC.
- Add missed chunk in previous driver code MFC.

Sponsored by:	Mellanox Technologies
MFC: r273034

Add one more AMD Kaveri APU device ID.

Submitted by:	Remy Nonnenmacher <remy.nonnenmacher@activnetworks.com>
Add basic UEFI boot procedure manpage

MFC of r273218 and r273235.
Fix rtsold(8) remote buffer overflow vulnerability. [SA-14:20]

Fix memory leak in sandboxed namei lookup. [SA-14:22]
MFC r273402:
  Fix an issue where a FreeBSD virtual machine provisioned in
  the Microsoft Azure service does not recognize the second
  attached disk on the system.

PR:		194376
Insta-MFC OK:	re (rodrigc)
Sponsored by:	The FreeBSD Foundation
Bump __FreeBSD_version to track SA-14:20, SA-14:21, SA-14:22,
SA-14:23

Approved by:	re (implicit)
Sponsored by:	The FreeBSD Foundation
MFC r272796:

Add M_FLOWID to M_COPYFLAGS

The M_FLOWID flag should be propagated to the new mbuf pkthdr in
m_move_pkthdr() and m_dup_pkthdr(). The new mbuf already got the
existing flowid value, but would be ignored since the flag was
not set.
MFC r272573:

  Change the UMA mutex into a rwlock

  Acquire the lock in read mode when just needed to ensure the stability
  of the keg list. The UMA lock may be held for a long time (relatively
  speaking) in uma_reclaim() on machines with lots of zones/kegs. If the
  uma_timeout() would fire during that period, subsequent callouts on that
  CPU may be significantly delayed.
MFC r273129:
Implement FIODTYPE for master ptys.
MFC r273130:
Change the deadfs poll VOP to return POLLIN|POLLRDNORM if the caller
is interested in i/o state.  Return POLLNVAL for invalid bits, similar
to poll_no_poll().
MFC r273131:
When vnode bypass cannot be performed on the cdev file descriptor for
read/write/poll/ioctl, call standard vnode filedescriptor fop.
MFC r273132:
Style changes for deadfs.
MFC r273088:

Add support for the __aeabi_c*cmp* functions. These are similar to the
existing functions with the exception they use the condition flags to
store the result.
MFC r271692:
Fix a typo.
MFC r263264 (by glebius):

  Make talk(1) capable of displaying UTF-8 characters.

  Sponsored by:	Nginx, Inc.