structure is zeroed, by setting the VNET after checking the mbuf count
for zero. It appears there are some cases with early interrupts on some
network devices which still trigger page-faults on accessing a NULL "ifp"
pointer before the TCP LRO control structure has been initialized.
This basically preserves the old behaviour, prior to
9ca874cf .

No functional change.

Reported by:	rscheff@
Differential Revision:	https://reviews.freebsd.org/D29564
MFC after:	2 weeks
Sponsored by:	Mellanox Technologies // NVIDIA Networking

Allow new enclosure to replace previously existing one if there is
no completely unused table entry, same as it is done for devices.

If we can not process DPM due to corruption -- wipe it and restart
from scratch.  Otherwise I don't see a way to recover persistence if
something go wrong and there is no BIOS to recover it for us.

Together this solves a problem that appeared when 9300-8i firmware
update to 16.00.10.00 somehow switched its mapping mode from Device
Persistence to Enclosure/Slot without wiping the DPM table.  It made
HBA completely unusable, since overflowed and conflicting mapping
table was unable to map any of enclosures and so devices.

Also while there make some enclosure mapping errors more informative.

MFC after:	1 month
Sponsored by:	iXsystems, Inc.

3e7bae08 turns the BUS_READ_IVAR() failure from a warning into a
KASSERT.  For certain PCI audio devices such like snd_csa(4) and
snd_emu10kx(4), the ac97_create() keeps the device handler generated
by device_add_child(pci_dev, "pcm"), which is not really a PCI device
handler.  This in turn causes the subsequent pci_get_subdevice()
inside ac97_initmixer() triggering a panic.

This patch tries to put a bandaid for the aforementioned pcm device
children such that they can use the correct PCI handler(from parent)
to avoid a KASSERT panic in the INVARIANTS kernel.

Tested with:	snd_csa(4), snd_ich(4), snd_emu10kx(4)
Reviewed by:	imp
MFC after:	1 month

When the NFSv4.1/4.2 server does a callback to a client
on the back channel, it will use a session slot in the
back channel session. If the back channel has failed,
the callback will fail and, without this patch, the
session slot will not be released.
As more callbacks are attempted, all session slots
can become busy and then the nfsd thread gets stuck
waiting for a back channel session slot.

This patch frees the session slot upon callback
failure to avoid this problem.

Without this patch, the problem can be avoided by leaving
delegations disabled in the NFS server.

MFC after:	2 weeks

Sponsored by:	The FreeBSD Foundation

MFC after:	2 weeks
Sponsored by:	Chelsio Communications

This fixes a bug in an earlier change to move tree rotation to
the end of the update where the step to make room for the new
preworld tree was deleting the old "current" tree instead of
the old "preworld" tree.

Reported by:	olivier, dhw
Fixes:		0611aec3
MFC after:	2 weeks

MFC after:	1 week
Sponsored by:	The FreeBSD Foundation

This reverts a portion of 27457983 ("capsicum: Limit socket
operations in capability mode") as at least rtsol and dhcpcd rely on
being able to configure network interfaces while in capability mode.

Reported by:	bapt, Greg V
Sponsored by:	The FreeBSD Foundation

This logic was accidentally changed in 67f2f67f

Reported By:	olivier
X-MFC-With:	67f2f67f
Tested By:	kp
Reviewed By:	kp, melifaro
Fixes:		67f2f67f ("Update rtsock_l3 test after 2fe5a794")
Differential Revision: https://reviews.freebsd.org/D29944

Changes to the LRO code have exposed a bug in iflib where devices
which are not capable of doing LRO are still calling
tcp_lro_flush_all(), even when they have not initialized the LRO
context. This used to be mostly harmless, but the LRO code now sets
the VNET based on the ifp in the lro context and will try to access it
through a NULL ifp resulting in a panic at boot.

To fix this, we unconditionally initializes LRO so that we have a
valid LRO context when calling tcp_lro_flush_all(). One alternative is
to check the device capabilities before calling tcp_lro_flush_all() or
adding a new state flag in the ctx. However, it seems unwise to add an
extra, mostly useless test for higher performance devices when we can
just initialize LRO for all devices.

Reviewed by: erj, hselasky, markj, olivier
Sponsored by: Netflix
Differential Revision: https://reviews.freebsd.org/D29928

It can be called to (re)apply the settings in the driver softc to the
hardware.

MFC after:	2 weeks
Sponsored by:	Chelsio Communications

There are two kinds of routines in the driver that read statistics from
the hardware: the cxgbe_* variants read the per-port MPS/MAC registers
and the vi_* variants read the per-VI registers.  They can be called
from the 1Hz callout or if_get_counter.  All stats collection now takes
place under the callout lock and there is a new flag to indicate that
these routines should not access any hardware register.

MFC after:	2 weeks
Sponsored by:	Chelsio Communications

Found in "Understanding and Detecting Disordered Error Handling with
Precise Function Pairing" by Qiushi Wu et al.

Reviewed by:	imp, jhb
MFC after:	1 week
Sponsored by:	The FreeBSD Foundation
Differential Revision:	https://reviews.freebsd.org/D29896

MFC after:	3 days

MFC after:	3 days
Sponsored by:	Chelsio Communications

Reported by:	olivier
MFC with:	e4643aa4

tod_pmtu_update was added to the kernel in 01d74fe1.

Sponsored by:	Chelsio Communications

Tested with:		cirrus-ci https://cirrus-ci.com/build/6012323274948608
Reviewed by:		emaste@, rgrimes@
Sponsored by:		Netflix
Differential Revision:	https://reviews.freebsd.org/D29869

PR:	255303
Approved by: 0mp (mentor)
Differential Revision: https://reviews.freebsd.org/D29924

While the PV SCSI SG list can handle 512k of SG entries, it can only do
so for I/O that's aligned to 4k or better. newfs_msdos does unaligned
I/O, so triggers too long for host errors in cam when a 512k I/O is
attempted. Prefer power of 2 256k to the absolute maximum 508k, though
that can be revisited should the latter show to give significant
performance improvement.

MFC After:		3 days
Tested by:		darius on discord (508k version of patch)
Sponsored by:		Netflix

Fixes segfault with the command `bhyve -s 0,virtio-scsi`, which is used
by some third party software to probe bhyve for virtio-scsi support.

Reviewed by:	jhb
MFC after:	1 day
Sponsored by:	iXsystems, Inc.
Differential Revision:	https://reviews.freebsd.org/D29926

Catching an in-flight unlocked vnode is fine here.

Reported by;	pho

PR: 254690
Approved by: mav(mentor)
MFC after: 2 weeks

PR:		253855
MFC after:	1 week
Sponsored by:	Mellanox Technologies // NVIDIA Networking

Sort the Garmin products while at it.

PR:		254664
MFC after:	1 week
Sponsored by:	Mellanox Technologies // NVIDIA Networking

Since then, the FreeBSD USB stack has got proper USB RNDIS support.

PR:		254345
MFC after:	1 week
Sponsored by:	Mellanox Technologies // NVIDIA Networking

Update the reference of which file to update in the doc tree when
bumping __FreeBSD_version.

This change is to catch up with commit f8fed61b80 in the doc repository.

MFC after:	3 days
Approved by:	lwhsu (mentor)
Sponsored by:	The FreeBSD Foundation
Differential Revision:	https://reviews.freebsd.org/D29920

Differential Revision: https://reviews.freebsd.org/D29900
Reviewed by:	hps, kp

Sponsored by:		Netflix

"i" is not used in this loop at all. There's no need to initialize and
increment it.

Reviewed by:		markj@
Sponsored by:		Netflix
Differential Revision:	https://reviews.freebsd.org/D29898

Reviewed by:	mhorne
Sponsored by:	DARPA
Differential Revision:	https://reviews.freebsd.org/D29764

Previously, a page fault taken during copyin/out and related functions
would run the entire fault handler while permitting direct access to
user addresses.  This could also leak across context switches (e.g. if
the page fault handler was preempted by an interrupt or slept for disk
I/O).

To fix, clear SUM in assembly after saving the original version of
SSTATUS in the supervisor mode trapframe.

Reviewed by:	mhorne, jrtc27
Sponsored by:	DARPA
Differential Revision:	https://reviews.freebsd.org/D29763

A slight mix-up of the flags means this case isn't triggered when it
should be. Now, `pmcstat -s event -t 1234` will print the correct
error message.

MFC after:	1 week
Sponsored by:	The FreeBSD Foundation

For an infrequent event, pmcstat may report (u_long)-1 for CPUs where
the counter was never incremented. Just set this to zero, instead.

ev->ev_count is passed as the 'count' argument to pmc_allocate(3), but
this wasn't always the case.

Reviewed by:	gnn
MFC after:	1 week
Sponsored by:	The FreeBSD Foundation
Differential Revision:	https://reviews.freebsd.org/D29887

This was added in b2ca2e50, and serves to provide an initial value
to the PMC, eliminating the need for a second syscall via pmc_set(3).

Reviewed by:	gnn, 0mp (manpages)
MFC after:	1 week
Sponsored by:	The FreeBSD Foundation
Differential Revision:	https://reviews.freebsd.org/D29885

Notify the TOE driver when when an ICMP type 3 code 4 (Fragmentation
needed and DF set) message is received for an offloaded connection.
This gives the driver an opportunity to lower the path MTU for the
connection and resume transmission, much like what the kernel does for
the connections that it handles.

Reviewed by:	glebius@
Sponsored by:	Chelsio Communications
Differential Revision:	https://reviews.freebsd.org/D29755

Also add an M_ASSERTMAPPED() macro to verify that all mbufs in the chain
are mapped.  Use it in ipfw_nat, which operates on a chain returned by
m_megapullup().

PR:		255164
Reviewed by:	ae, gallatin
MFC after:	1 week
Sponsored by:	The FreeBSD Foundation
Differential Revision:	https://reviews.freebsd.org/D29838

-swap disk stat based on new size.

Display corrupts after resizing a window.
Process SIGWINCH to redraw all window.

Submitted by:   Yoshihiro Ota ota@j.email.ne.jp
Differential Revision:  https://reviews.freebsd.org/D29337

Stop free() even if kvm_getprocs as we can come back but set nprocs = 0.
Check nprocs in showpigs() to ensure not try displaying with kvm_getprocs failed.
Current code can have pt with non-null after kvm_getprocs() failure.

Replace to realloc for simpler operations.

Submitted by:	Yoshihiro Ota ota@j.email.ne.jp
Reviewed by:	mckusick@
Differential Revision:	https://reviews.freebsd.org/D29303