Daniel reported that NFSv4 mounts were not working despite having
set "nfsv4_server_enable=YES" in /etc/rc.conf.  Mountd was logging a
message that there was no /etc/exports file.
He noted that creating a /etc/exports file with a "V4:" line in it
was needed make NFSv4 mounts work.
At least one "V4:" line in one of the exports(5) file(s) is needed to
make NFSv4 mounts work. This patch fixes mountd.c so that it logs a
message indicting that there is no "V4:" line in any exports(5)
file when NFSv4 mounts are enabled.
To avoid this message being generated erroneously, /etc/rc.d/mountd
is updated to make sure vfs.nfsd.server_max_nfsvers is properly set
before mountd(8) is started.

Reported by:	debdrup
PR:	253901
MFC after:	2 weeks

When we enter C2+ state via memory read, it may take chipset some
time to stop CPU.  Extra register read covers that time.  But MWAIT
makes CPU stop immediately, so we don't need to waste time after
wakeup with interrupts still disabled, increasing latency.

On my system it reduces ping localhost latency, waking up all CPUs
once a second, from 277us to 242us.

MFC after:	1 month

Even though the information is very limited, it seems the intent of
this flag is to control ACPI_BITREG_BUS_MASTER_STATUS use for C3,
not force ACPI_BITREG_ARB_DISABLE manipulations for C2, where it was
never needed, and which register not really doing anything for years.
It wasted lots of CPU time on congested global ACPI hardware lock
when many CPU cores were trying to enter/exit deep C-states same time.

On idle 80-core system it pushed ping localhost latency up to 20ms,
since badport_bandlim() via counter_ratecheck() wakes up all CPUs
same time once a second just to synchronously reset the counters.
Now enabling C-states increases the latency from 0.1 to just 0.25ms.

Discussed with:	kib
MFC after:	1 month

config_intrhook doesn't need to be a two-pointer TAILQ. We rarely add/delete
from this and so those need not be optimized. Instaed, use the one-pointer
STAILQ plus a uintptr_t to be used as a flags word. This will allow these
changes to be MFC'd to 12 and 13 to fix a race in removable devices.

Feedback from: jhb
Reviewed by: mav
Differential Revision:	https://reviews.freebsd.org/D29004

P2P ifa may require 2 routes: one is the loopback route, another is
 the "prefix" route towards its destination.

Current code marks loopback routes existence with IFA_RTSELF and
 "prefix" p2p routes with IFA_ROUTE.

For historic reasons, we fill in ifa_dstaddr for loopback interfaces.
To avoid installing the same route twice, we preemptively set
 IFA_RTSELF when adding "prefix" route for loopback.
However, the teardown part doesn't have this hack, so we try to
 remove the same route twice.

Fix this by checking if ifa_dstaddr is different from the ifa_addr
 and moving this logic into a separate function.

Reviewed By: kp
Differential Revision: https://reviews.freebsd.org/D29121
MFC after:	3 days

PR:		254137
Reported by:	Mina Galić <me@igalic.co>
MFC after:	3 days
Fixes:		f8bc74e2 ("tap: add support for virtio-net offloads")

Misbehavior has been observed with TSC under VirtualBox, where threads
doing small sleeps (~1 second) may miss their wake up and hang around
in a sleep state indefinitely.  Switching back to ACPI-fast decidedly
fixes it, so stop using TSC on VirtualBox at least for the time being.

This partially reverts 84eaf2cc, applying it only to VirtualBox and
increasing the quality to 0. Negative qualities can never be chosen and
cannot be chosen with the tunable recently added. If we do not have a
timecounter with a higher quality than 0, then TSC does at least leave
the system mostly usable.

PR:		253087
Reviewed by:	emaste, kib
MFC after:	3 days
Differential Revision:	https://reviews.freebsd.org/D29132

MFC after:	3 days

The structure was renamed while refactoring Netflix's KTLS changes for
upstreaming, but the original name remained in tcp.4 and was
subsequently copied to ktls.4.

PR:		254141
Reported by:	asomers
MFC after:	3 days

df554850 fixed a leak that I had initially fixed in a11009dc.

Fixes:	a11009dc

This structure is shared among multiple instances of a driver, so we
should ensure that it doesn't somehow get treated as if there's a
separate instance per interface.  This is especially important for
software-only drivers like wg.

DEVICE_REGISTER() still returns a void * and so the per-driver sctx
structures are not yet defined with the const qualifier.

Reviewed by:	gallatin, erj
MFC after:	2 weeks
Sponsored by:	The FreeBSD Foundation
Differential Revision:	https://reviews.freebsd.org/D29102

Other kernel sanitizers (KMSAN, KASAN) require interceptors as well, so
put these in a more generic place as a step towards importing the other
sanitizers.

No functional change intended.

MFC after:	1 week
Sponsored by:	The FreeBSD Foundation
Differential Revision:	https://reviews.freebsd.org/D29103

ath_hal is compiled into the kernel by default and so always prints a
message to dmesg even when the system has no ath hardware.

MFC after:	1 week
Sponsored by:	The FreeBSD Foundation

timer_settime(2) may be used to configure a timeout in the past.  If
the timer is also periodic, we also try to compute the number of timer
overruns that occurred between the initial timeout and the time at which
the timer fired.  This is done in a loop which iterates once per period
between the initial timeout and now.  If the period is small and the
initial timeout was a long time ago, this loop can take forever to run,
so the system is effectively DOSed.

Replace the loop with a more direct calculation of
(now - initial timeout) / period to compute the number of overruns.

Reported by:	syzkaller
Reviewed by:	kib
MFC after:	1 week
Sponsored by:	The FreeBSD Foundation
Differential Revision:	https://reviews.freebsd.org/D29093

MFC after:	1 week
Sponsored by:	The FreeBSD Foundation

MFC after:	1 week
Sponsored by:	The FreeBSD Foundation

MFC after:	1 week
Sponsored by:	The FreeBSD Foundation

Reviewed by:	grehan
Sponsored by:	The FreeBSD Foundation
MFC after:	3 days
Differential Revision:	https://reviews.freebsd.org/D29011

Sponsored by:	The FreeBSD Foundation
MFC after:	1 week

This fixes tests/lib/msun/logarithm_test after compiling the test with
-fno-builtin (D28577). Adding invln10_lo + invln10_10 results in
FE_INEXACT (for all inputs) and the same for the log2l invln2_lo + invln2_hi.
This patch avoids FE_INEXACT (for exact results such as 0) by defining a
constant and using that.

Reviewed By:	dim
Differential Revision: https://reviews.freebsd.org/D28786

The argument has to be a single whitespace-separate value. While touching
all these lines also add ksh93, since `atf_set "require.progs"` overrides
the default value specified in the Kyuafile. This then results in tests
being executed despite ksh93 not being installed.

Reviewed By:	asomers
Differential Revision: https://reviews.freebsd.org/D29066

When I synchronized kern.mk with bsd.sys.mk, I accidentally changed
CCLDFLAGS to LDFLAGS which is not used by the kernel builds. This commit
should unbreak the GitHub actions cross-build CI. I didn't notice it
locally because cheribuild already passes -fuse-ld in the linker flags as
it predates this being done in the makefiles.

Reported By:	Jose Luis Duran
Fixes:		172a624f ("Silence annoying and incorrect non-default linker warning with GCC")

Update tests to reflect the changes of "open(2): Remove O_BENEATH and
AT_BENEATH" in 20e91ca3.

While we're here, sync up with OpenBSD and don't use a keypair !kp_valid

MFC after:	3 days

m_defrag() will not free the chain on failure, leaking the mbuf.

Obtained from:	OpenBSD
MFC after:	3 days

The keypair lock is not taken until later.

Obtained from:	Jason A. Donenfeld via OpenBSD
MFC after:	3 days

Reported by:	hrs
MFC after:	1 week

Noted and reviewed by:	kevans
MFC after:	1 week
Sponsored by:	The FreeBSD Foundation
Differential revision:	https://reviews.freebsd.org/D29122

The save/restore feature uses a unix domain socket to send messages
from bhyvectl(8) to a bhyve(8) process. A datagram socket will suffice
for this.

An added benefit of using a datagram socket is simplified code. For
bhyve, the listen/accept calls are dropped; and for bhyvectl, the
connect() call is dropped.

EPRINTLN handles raw mode for bhyve(8), use it to print error messages.

Reviewed by:	jhb
Differential Revision:	https://reviews.freebsd.org/D28983

It's not needed.  Removing it is a small improvement in portability.

Sponsored by:	Dell EMC Isilon

When the netdump host name fails to resolve, don't print errno, since
it's irrelevant.  We might as well use a different exit status, too.

Sponsored by:	Dell EMC Isilon

The current preference number were copied from IPv4 code,
 assuming 500k routes to be the full-view. Adjust with the current
 reality (100k full-view).

Reported by:	Marek Zarychta <zarychtam at plan-b.pwste.edu.pl>
MFC after:	3 days

Initialization of the XTS key schedule was accidentally dropped
when adding AES-GCM support so all-zero schedule was used instead.
This rendered previously created GELI partitions unusable.
This change restores proper XTS key schedule initialization.

Reported by:	Peter Jeremy <peter@rulingia.com>
MFC after:	immediately

The example in the manual page of wg(4) for connecting to a
peer was missing the 'public-key' ifconfig(8) keyword and for the
addressed peer the port must be specified.

PR:	253866
Reported by:	Sergey Akhmatov <sergey at akhmatov dot ru>
Reviewed by:	debdrup
MFC after:	3 days
Differential Revision:	https://reviews.freebsd.org/D29115

Add missing #ifndef/#define/#endif guards against multiple inclusions
to ieee80211_ratectl.h as they are missing.

MFC after:	3 days
Sponsored-by:	Rubicon Communications, LLC ("Netgate")

This reverts commit 4287fa84.

Data Output Enable Control register is inverted – 0 means output direction.
Reflect this fact in code.

MFC after:	3 weeks

Use errno to print a more descriptive error message when vm_open() fails

libvmm: preserve errno when vm_device_open() fails

vm_destroy() squashes errno by making a dive into sysctlbyname() - we
can safely skip vm_destroy() here since it's not doing any critical
clean up at this point. Replace vm_destroy() with a free() call.

PR:             250671
MFC after:      3 days
Submitted by:   marko@apache.org
Reviewed by:	grehan
Differential Revision:	https://reviews.freebsd.org/D29109