Fix the USB audio feedback endpoint algorithm. There should not
be any need to bias the returned value.

Reported by:	Craig Leres <leres@ee.lbl.gov>
Fix for duplicate sample rate detection after recent patches.
When rebooting (exiting) from the BTX loader, make sure to restore the
GDT from the correct segment, otherwise a triple fault would be caused.
In some virtual environments (VMware, VirtualBox, etc) this could lead
to a unhandled error or hang in the guest emulation software.

Thanks to avg and jhb for a few hints in the right direction.

Noticed by:	Jeremy Chadwick <jdc@koitsu.org> (and many others)
MFC after:	1 week
Fix N32/N64 ABIs to use proper registers after recent changes.

Pointy Hat to: imp
This fixes the issue with the "randomly changing" default
route. What it was is there are two places in ip_output.c
where we do a goto again. One place was fine, it
copies out the new address and then resets dst = ro->rt_dst;
But the other place does *not* do that, which means earlier
when we found the gateway, we have dst pointing there
aka dst = ro->rt_gateway is done.. then we do a
goto again.. bam now we clobber the default route.

The fix is just to move the again so we are always
doing dst = &ro->rt_dst; in the again loop.

PR:	 174749,157796
MFC after:	1 week
Move hptmv and mpt drivers shutdown a bit later to the SHUTDOWN_PRI_LAST
stage of shutdown_post_sync.  That should allow CAM to do final cache flush
at the SHUTDOWN_PRI_DEFAULT without using polling magic.

MFC after:	3 days
MFV r249857:

Merge vendor bugfix for a possible deadlock related to async destroy
and improve write performance by introducing a new lock protecting
tx_open_txg.

Illumos ZFS issues:
  3642 dsl_scan_active() should not issue I/O to determine if async
       destroying is active
  3643 txg_delay should not hold the tc_lock

MFC after:	1 week
getdtablesize(2): Describe what this function actually does.

getdtablesize() returns the limit on new file descriptors; this says nothing
about existing descriptors.

MFC after:	1 week
Fix the Dvorak Programmer Keymap

PR:		conf/177572
Submitted by:	Sean DuBois <sean@siobud.com>
Add myself to the committers list.
Add myself as a src committer

Approved by:	ken (mentor)
Introduce kernel coredumps to ppc32 AIM.  Leeched from the booke code.

MFC after:	2 weeks
Fix mips64 and mipsn32 bilds by using proper register names.
Add RIP-relative addressing to the instruction decoder.
Rework the guest register fetch code to allow the RIP to
be extracted from the VMCS while the kernel decoder is
functioning.

Hit by the OpenBSD local-apic code.

Submitted by:	neel
Reviewed by:	grehan
Obtained from:	NetApp
Remove the Fortran directories.
Use the defines from pcb.h over the ones from regnum.h for this 'C'
code. In theory, the ones from regnum.h should be used only for
assembler code.
Make it possible to include this file in assembler .S sources.
Respect the enoent_ok flag if reporting error for holding an non-existing
snapshot.

Related illumos ZFS issue:
  3699 zfs hold or release of a non-existent snapshot does not output error

Reported by:	Steven Hartland <smh@FreeBSD.org>
MFC after:	3 days
revert r248644 because of the regression for usdt probes

USDT probes are advertised to kernel by initialization code with
atrribute((constructor))).  It seems that on Solaris the .init-ish code
of the main object is executed before RD_PREINIT point is hit.  On
FreeBSD that is not the case.  And because on FreeBSD there is no other
well-defined point between RD_PREINIT and main() we have to parse a
DTrace script when main is hit, for time being.

A footnote: currently we actually post RD_POSTINIT event, but that's a
bug because the event is triggered by hitting r_debug_state which
happens before any init code is executed.

Reported by:	markj
Fix installworld with DB_FROM_SRC after r249807

Approved by:	bapt
Reported by:	Tom Everett