Email address has changed, uses consistent name (Matthew, not Matt)

Reported by:	Matthew Macy <mmacy@mattmacy.io>
Differential Revision:	https://reviews.freebsd.org/D13537

gmirror does not perform any sorting of I/O requests, so the bioq API
doesn't provide any advantages over plain TAILQs. The API also does not
provide operations needed by an upcoming change.

No functional change intended. The diff shrinks the geom_mirror.ko
text and the gmirror softc slightly.

Tested by:	pho (part of a larger patch)
MFC after:	1 week
Sponsored by:	Dell EMC Isilon

Add atomic_load_<type> and atomic_store_<type>, and explain why they
exist.

Define the synchronizes-with relationship and its effects.

Reorder and revise some of the existing text.  For example, more
precisely describe when ordinary accesses are atomic.

Reviewed by:	jhb, kib
MFC after:	1 week
Differential Revision:	https://reviews.freebsd.org/D13522

the 32-bit cookie can be sign-extended on its way out of the loader and
through Open Firmware. If sign-extended, the in-kernel check of its value
would fail on 64-bit systems, resulting in a mountroot prompt. Solve this
by telling the kernel to ignore the high-order bits.

PR:		kern/224437
Submitted by:	Gustavo Romero

applied relocation offset in link_elf.c works as intended. We may want to
revisit how that works in future, for example by having elf_reloc_self()
actually store the numbers it is using rather than computing them later,
but this fixes symbol lookup after r326203.

Reported by:	andreast@
Pointy hat to:	me

The IA32 memory model guarantees that all writes are seen in the program
order.  Also, any access to the uncacheable memory flushes the store
buffers.  As the consequence, SFENCE instruction is (almost) never needed,
in particular, it is not needed to ensure the correct order of updates as
seen by a PCIe device.

Use atomic_thread_fence_rel() instead of wb() to only emit compiler barriers
on x86 there.  Other architectures get the right barrier instruction as
well.

Reviewed by:	hselasky
Sponsored by:	Mellanox Technologies
MFC after:	1 week

Reviewed by:	alc, jhb
Sponsored by:	The FreeBSD Foundation
MFC after:	1 week
Differential revision:	https://reviews.freebsd.org/D13534

In this case volatile qualifiers enusre that a compiler does not
optimize the accesses out.

Reviewed by:	alc, jhb
Sponsored by:	The FreeBSD Foundation
MFC after:	1 week
Differential revision:	https://reviews.freebsd.org/D13534

They provide relaxed-ordered atomic access semantic.  Due to the
FreeBSD memory model, the operations are syntaxical wrappers around
the volatile accesses.  The volatile qualifier is used to ensure that
the access not optimized out and in turn depends on the volatile
semantic as implemented by supported compilers.

The motivation for adding the operation is to help people coming from
other systems or knowing the C11/C++ standards where atomics have
special type and require use of the special access operations.  It is
still the case that FreeBSD requires plain load and stores of aligned
integer types to be atomic.

Suggested by:	jhb
Reviewed by:	alc, jhb
Sponsored by:	The FreeBSD Foundation
MFC after:	1 week
Differential revision:	https://reviews.freebsd.org/D13534

changed worked to capture dumps for me. However, the test for
SCHEDULER_STOPPED() isn't right. We can also call the dump routine
from ddb, in which case the scheduler is still running. This leads to
an assertion panic that we're sleeping when we shouldn't. Instead, use
the proper test for dumping or not. This brings us in line with other
places that do special things while we're doing polled I/O like this.

Noticed by: pho@
Differential Revision: https://reviews.freebsd.org/D13531

Sponsored by: Netflix

Sponsored by: Netflix

removing this argument, and expanding when rc is NULL. This
effectively completes the back out of custom scripts for tftp booted
loaders from r269153 that was started in r292344 with the new path
tricks that obsoleted it.

Submitted by: Netflix

used once, inside an #ifdef where it would be defined to be return.

Sponsored by: Netflix

shell scripts in scripts don't need
to be chmod +x to work. In fact most are not.
Of the tests I found from a simple search:
65 are chmod +x
84 are chmod -x

simply disable the check for test shell scripts.

Recommit requested by:	cem, rgrimes

It is not necessary and matches what bfd and gold do.

This was a regression from [LLVM] r315658.

Obtained from:	LLVM r321023 by Rafael Espíndola

By the ACPI standard (ACPI 5 chapter 8.4 Declaring Processors) Processors
can be implemented in 2 distinct ways:

* Through a Processor object type (which provides P_BLK)
* Through a Device object type

Prior to this change, the FreeBSD driver only supported the former.  AMD
Epyc / Poweredge systems we are testing both implement the latter only.  Add
the missing support.

Because P_BLK is not defined in the device object case, C-states entering
must be completely controlled via _CST methods rather than P_LVL2/3.

John Baldwin points out that ACPI 6.0 formally deprecates the Processor
keyword, so eventually processors will only be enumerated as Device objects.

Submitted by:	attilio
Reviewed by:	jhb, markj, Anton Rang <rang AT acm.org>
Relnotes:	maybe
Sponsored by:	Dell EMC Isilon
Differential Revision:	https://reviews.freebsd.org/D13457

Print a qemu line to a shell script to ease testing each image
Start to support multiple architectures (still very green)
Create /etc/rc that echos success and halts the system for better
automation (also include halt)
Create /etc/fstab on a per-boot type to test loader's passing root
to kernel.

This lets me run a test, connect to it with telnet and get either a
timeout, or a report of success.

Sponsored by: Netflix

Some of the ptrace tests need to wait for a child process to become a
zombie before preceding.  The parent process polls the child process
via the kern.proc.pid sysctl to wait for it to become a zombie.
Previously the code polled until the sysctl failed with ESRCH.  Now it
will poll until either the sysctl fails with ESRCH (for compatiblity
with older kernels) or returns a kinfo_proc structure with the ki_stat
field set to SZOMB.

Reported by:	Jenkins
Tested by:	markj
Discussed with:	mjg
MFC after:	1 week

we have more than one by checking the actual quirk bit before delaying
the reset.

Noticed by: rpokala@

bug that requires 'hands off' for a period of time (2.3s) before we
check the RDY bit. Sicne this is a very odd quirk for a very limited
selection of drives, do this as a quirk. This prevented a successful
reset of the card when the card wedged.

Also, make sure that we comply with the advice from section 3.1.5 of
the 1.3 spec says that transitioning CC.EN from 0 to 1 when CSTS.RDY
is 1 or transitioning CC.EN from 1 to 0 when CSTS.RDY is 0 "has
undefined results". Short circuit when EN == RDY == desired state.

Finally, fail the reset if the disable fails. This will lead to a
failed device, which is what we want. (note: nda device needs
work for coping with a failed device).

Sponsored by: Netflix
Differential Revision: https://reviews.freebsd.org/D13389

dtrace_gethrtime() may be called outside of probe context, and in
particular, from the DTRACEIOC_BUFSNAP handler.

Disable interrupts rather than using sched_pin() to help ensure that
we don't call any external functions when in probe context.

PR:		218452
MFC after:	1 week

of low physical memory:

Update the comment about leaving the permanent mapping in place.  This
also improves the wording of the comment.  PTD 0 is still left alone
because it is fairly important that it was unmapped earlier, and the
comment now describes the unmapping of the other low PTDs that the code
actually does.

Reviewed by:	kib

it by a transient double mapping for the one instruction in ACPI wakeup
where it is needed (and for many surrounding instructions in ACPI resume).
Invalidate the TLB as soon as convenient after undoing the transient
mapping.  ACPI resume already has the strict ordering needed for this.

This fixes the non-trapping of null pointers and other garbage pointers
below NBPDR (except transiently).  NBPDR is quite large (4MB, or 2MB for
PAE).

This fixes spurious traps at the first instruction in VM86 bioscalls.
The traps are for transiently missing read permission in the first
VM86 page (physical page 0) which was just written to at KERNBASE in
the kernel.  The mechanism is unknown (it is not simply PG_G).

locore uses a similar but larger transient double mapping and needs
it for 2 instructions instead of 1.  Unmap the first PDE in it after
the 2 instructions to detect most garbage pointers while bootstrapping.
pmap_bootstrap() finishes the unmapping.

Remove the avoidance of the double mapping for a recently fixed special
case.  ACPI resume could use this avoidance (made non-special) to avoid
any problems with the transient double mapping, but no such problems
are known.

Update comments in locore.  Many were for old versions of FreeBSD which
tried to map low memory r/o except for special cases, or might have
allowed access to low memory via physical offsets.  Now all kernel
maps are r/w, and removal of of the double map disallows use of physical
offsets again.

when KERNLOAD is smaller than NBPDR (not the default) and PG_G is
enabled (the default if the CPU supports it).  This case has relatively
minor problems with coherency of the permanent double mapping, but the
fix in r167869 to improve coherency creates page tables with 3 different
errors so never worked.

The permanent double mapping is fundamentally broken and will be removed
soon.  It fundamentally breaks trapping for null pointers and requires
complications to avoid cache coherency bugs.  It is currently used for
only a single instruction in ACPI resume,

Many fixes VM86 and/or ACPI and/or the double map were attempted near
r1200000.  r167869 attempted to fix cache coherency bugs in an unusual
case, but the bugs were unreachable because older errors in page tables
caused a crash first.

This commit just makes r167869 work as intended.  Part 1 of these fixes
fixed the other errors, but also stopped mapping the PDE for KERNBASE
as a large page, so double mapping of this PDE only causes the same
problems as when KERNLOAD is the default.  Except for the problem of
trapping null pointers, r167869 could be used to fix these problems,
but it is inactive in usual cases.  The only known other problem is
that incoherent permissions for page 0 cause spurious traps in VM86
BIOS calls.

Reviewed by:	kib

When building the command to execute for compression, newsyslog was modifying
the generic arguments array instead of its own copy.
Meaning on the second file to compress with the same arguments, the command line
was not the one expected.
Fix it by creating one copy of the arguments per execution and modifying that
copy.

While here, print the command line executed in verbose mode.

Reported by:	many

when KERNLOAD is not a multiple of NBPDR (not the default) and PSE is
enabled (the default if the CPU supports it).  Addresses in PDEs must
be a multiple of NBPDR in the PSE case, but were not so in the crashing
case.

KERNLOAD defaults to NBPDR.  NBPDR is 4 MB for !PAE and 2 MB for PAE.
The default can be changed by editing i386/include/vmparam.h or using
makeoptions.  It can be changed to less than NBPDR to save real and
virtual memory at a small cost in time, or to more than NBPDR to waste
real and virtual memory.  It must be larger than 1 MB and a multiple of
PAGE_SIZE.  When it is less than NBPDR, it is necessarily not a multiple
of NBPDR.  This case has much larger bugs which will be fixed in part 2.

The fix is to only use PSE for physical addresses above <KERNLOAD
rounded _up_ to an NBPDR boundary>.  When the rounding is non-null,
this leaves part of the kernel not using large pages.  Rounding down
would avoid this pessimization, but would break setting of PAT bits
on i/o pages if it goes below 1MB.  Since rounding down always goes
below 1MB when KERNLOAD < NBPDR and the KERNLOAD > NBPDR case is not
useful, never round down.

Fix related style bugs (e.g., wrong literal values for NBPDR in comments).

Reviewed by:	kib

to loader.mk.

Sponsored by: Netflix

HELP_FILES is a loader only thing, so move it to loader.mk. Only
generate the help file if HELP_FILES is defined. Adjust Makefiles to
new convention. Fix a few cases where ${.CURDIR}/ was missing
resulting in missing bits from the help files.

Sponsored by: Netflix

A comment in bcm_bsc_fill_tx_fifo() even lists sc_totlen > 0 as a
precondition for calling the routine.   I apparently forgot to make the
code do what my comment said.

while renaming variables in a previous change.

Otherwise a poorly timed lowmem event may attempt to acquire a destroyed
lock. Unregister the handler before destroying the ARC reclaim thread.

Reported by:	gjb
MFC after:	1 week
Differential Revision:	https://reviews.freebsd.org/D13480

Produces the same .o's, verified with md5.

Sponsored by: Netflix

due to its vulgar nature.

Submitted by: sevan@
Differential Revision: https://reviews.freebsd.org/D13510

We may need to initialize multiple inode blocks before writing a given
inode. makefs(8) was only initializing a single block at a time, so
certain inode allocation patterns could lead to a situation where it
wrote an inode to an uninitialized block. That inode might be clobbered
by a later initialization, resulting in a filesystem image containing
directory entries that point to a seemingly unused inode.

Reviewed by:	imp
MFC after:	1 week
Differential Revision:	https://reviews.freebsd.org/D13505

This change copies the existing amd64_cloudabi64.c to amd64_cloudabi32.c
and reimplements the functions for fetching system call arguments and
return values to use the same scheme as used by the vDSO that is used
when running cloudabi32 executables.

As arguments are automatically padded to 64-bit words by the vDSO in
userspace, we can copy the arguments directly into the array used by
truss(8) internally.

Reviewed by:	jhb
Differential Revision:	https://reviews.freebsd.org/D13516

In order to let truss(8) support tracing of 32-bit CloudABI
applications, we need to add a new ABI type to libsysdecode. We can
reuse the existing errno mapping table. Also link in the cloudabi32
system call table to translate system call names.

While there, remove all of the architecture ifdefs. There are not
needed, as the CloudABI data types and system call tables build fine on
any architecture. Building this unconditionally will make it easier to
do tracing for different compat modes, emulation, etc.

Reviewed by:	jhb
Differential Revision:	https://reviews.freebsd.org/D13516

5.0.1 release (upstream r320880).

Relnotes:	yes
MFC after:	2 weeks

As of r326897 ld.lld can link a working i386 libc.so, so we no longer
need to force use of ld.bfd.

Sponsored by:	The FreeBSD Foundation