Merge tag 'net-next-6.3' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-nextgrafted

Pull networking updates from Jakub Kicinski:
 "Core:

   - Add dedicated kmem_cache for typical/small skb->head, avoid having
     to access struct page at kfree time, and improve memory use.

   - Introduce sysctl to set default RPS configuration for new netdevs.

   - Define Netlink protocol specification format which can be used to
     describe messages used by each family and auto-generate parsers.
     Add tools for generating kernel data structures and uAPI headers.

   - Expose all net/core sysctls inside netns.

   - Remove 4s sleep in netpoll if carrier is instantly detected on
     boot.

   - Add configurable limit of MDB entries per port, and port-vlan.

   - Continue populating drop reasons throughout the stack.

   - Retire a handful of legacy Qdiscs and classifiers.

  Protocols:

   - Support IPv4 big TCP (TSO frames larger than 64kB).

   - Add IP_LOCAL_PORT_RANGE socket option, to control local port range
     on socket by socket basis.

   - Track and report in procfs number of MPTCP sockets used.

   - Support mixing IPv4 and IPv6 flows in the in-kernel MPTCP path
     manager.

   - IPv6: don't check net.ipv6.route.max_size and rely on garbage
     collection to free memory (similarly to IPv4).

   - Support Penultimate Segment Pop (PSP) flavor in SRv6 (RFC8986).

   - ICMP: add per-rate limit counters.

   - Add support for user scanning requests in ieee802154.

   - Remove static WEP support.

   - Support minimal Wi-Fi 7 Extremely High Throughput (EHT) rate
     reporting.

   - WiFi 7 EHT channel puncturing support (client & AP).

  BPF:

   - Add a rbtree data structure following the "next-gen data structure"
     precedent set by recently added linked list, that is, by using
     kfunc + kptr instead of adding a new BPF map type.

   - Expose XDP hints via kfuncs with initial support for RX hash and
     timestamp metadata.

   - Add BPF_F_NO_TUNNEL_KEY extension to bpf_skb_set_tunnel_key to
     better support decap on GRE tunnel devices not operating in collect
     metadata.

   - Improve x86 JIT's codegen for PROBE_MEM runtime error checks.

   - Remove the need for trace_printk_lock for bpf_trace_printk and
     bpf_trace_vprintk helpers.

   - Extend libbpf's bpf_tracing.h support for tracing arguments of
     kprobes/uprobes and syscall as a special case.

   - Significantly reduce the search time for module symbols by
     livepatch and BPF.

   - Enable cpumasks to be used as kptrs, which is useful for tracing
     programs tracking which tasks end up running on which CPUs in
     different time intervals.

   - Add support for BPF trampoline on s390x and riscv64.

   - Add capability to export the XDP features supported by the NIC.

   - Add __bpf_kfunc tag for marking kernel functions as kfuncs.

   - Add cgroup.memory=nobpf kernel parameter option to disable BPF
     memory accounting for container environments.

  Netfilter:

   - Remove the CLUSTERIP target. It has been marked as obsolete for
     years, and we still have WARN splats wrt races of the out-of-band
     /proc interface installed by this target.

   - Add 'destroy' commands to nf_tables. They are identical to the
     existing 'delete' commands, but do not return an error if the
     referenced object (set, chain, rule...) did not exist.

  Driver API:

   - Improve cpumask_local_spread() locality to help NICs set the right
     IRQ affinity on AMD platforms.

   - Separate C22 and C45 MDIO bus transactions more clearly.

   - Introduce new DCB table to control DSCP rewrite on egress.

   - Support configuration of Physical Layer Collision Avoidance (PLCA)
     Reconciliation Sublayer (RS) (802.3cg-2019). Modern version of
     shared medium Ethernet.

   - Support for MAC Merge layer (IEEE 802.3-2018 clause 99). Allowing
     preemption of low priority frames by high priority frames.

   - Add support for controlling MACSec offload using netlink SET.

   - Rework devlink instance refcounts to allow registration and
     de-registration under the instance lock. Split the code into
     multiple files, drop some of the unnecessarily granular locks and
     factor out common parts of netlink operation handling.

   - Add TX frame aggregation parameters (for USB drivers).

   - Add a new attr TCA_EXT_WARN_MSG to report TC (offload) warning
     messages with notifications for debug.

   - Allow offloading of UDP NEW connections via act_ct.

   - Add support for per action HW stats in TC.

   - Support hardware miss to TC action (continue processing in SW from
     a specific point in the action chain).

   - Warn if old Wireless Extension user space interface is used with
     modern cfg80211/mac80211 drivers. Do not support Wireless
     Extensions for Wi-Fi 7 devices at all. Everyone should switch to
     using nl80211 interface instead.

   - Improve the CAN bit timing configuration. Use extack to return
     error messages directly to user space, update the SJW handling,
     including the definition of a new default value that will benefit
     CAN-FD controllers, by increasing their oscillator tolerance.

  New hardware / drivers:

   - Ethernet:
      - nVidia BlueField-3 support (control traffic driver)
      - Ethernet support for imx93 SoCs
      - Motorcomm yt8531 gigabit Ethernet PHY
      - onsemi NCN26000 10BASE-T1S PHY (with support for PLCA)
      - Microchip LAN8841 PHY (incl. cable diagnostics and PTP)
      - Amlogic gxl MDIO mux

   - WiFi:
      - RealTek RTL8188EU (rtl8xxxu)
      - Qualcomm Wi-Fi 7 devices (ath12k)

   - CAN:
      - Renesas R-Car V4H

  Drivers:

   - Bluetooth:
      - Set Per Platform Antenna Gain (PPAG) for Intel controllers.

   - Ethernet NICs:
      - Intel (1G, igc):
         - support TSN / Qbv / packet scheduling features of i226 model
      - Intel (100G, ice):
         - use GNSS subsystem instead of TTY
         - multi-buffer XDP support
         - extend support for GPIO pins to E823 devices
      - nVidia/Mellanox:
         - update the shared buffer configuration on PFC commands
         - implement PTP adjphase function for HW offset control
         - TC support for Geneve and GRE with VF tunnel offload
         - more efficient crypto key management method
         - multi-port eswitch support
      - Netronome/Corigine:
         - add DCB IEEE support
         - support IPsec offloading for NFP3800
      - Freescale/NXP (enetc):
         - support XDP_REDIRECT for XDP non-linear buffers
         - improve reconfig, avoid link flap and waiting for idle
         - support MAC Merge layer
      - Other NICs:
         - sfc/ef100: add basic devlink support for ef100
         - ionic: rx_push mode operation (writing descriptors via MMIO)
         - bnxt: use the auxiliary bus abstraction for RDMA
         - r8169: disable ASPM and reset bus in case of tx timeout
         - cpsw: support QSGMII mode for J721e CPSW9G
         - cpts: support pulse-per-second output
         - ngbe: add an mdio bus driver
         - usbnet: optimize usbnet_bh() by avoiding unnecessary queuing
         - r8152: handle devices with FW with NCM support
         - amd-xgbe: support 10Mbps, 2.5GbE speeds and rx-adaptation
         - virtio-net: support multi buffer XDP
         - virtio/vsock: replace virtio_vsock_pkt with sk_buff
         - tsnep: XDP support

   - Ethernet high-speed switches:
      - nVidia/Mellanox (mlxsw):
         - add support for latency TLV (in FW control messages)
      - Microchip (sparx5):
         - separate explicit and implicit traffic forwarding rules, make
           the implicit rules always active
         - add support for egress DSCP rewrite
         - IS0 VCAP support (Ingress Classification)
         - IS2 VCAP filters (protos, L3 addrs, L4 ports, flags, ToS
           etc.)
         - ES2 VCAP support (Egress Access Control)
         - support for Per-Stream Filtering and Policing (802.1Q,
           8.6.5.1)

   - Ethernet embedded switches:
      - Marvell (mv88e6xxx):
         - add MAB (port auth) offload support
         - enable PTP receive for mv88e6390
      - NXP (ocelot):
         - support MAC Merge layer
         - support for the the vsc7512 internal copper phys
      - Microchip:
         - lan9303: convert to PHYLINK
         - lan966x: support TC flower filter statistics
         - lan937x: PTP support for KSZ9563/KSZ8563 and LAN937x
         - lan937x: support Credit Based Shaper configuration
         - ksz9477: support Energy Efficient Ethernet
      - other:
         - qca8k: convert to regmap read/write API, use bulk operations
         - rswitch: Improve TX timestamp accuracy

   - Intel WiFi (iwlwifi):
      - EHT (Wi-Fi 7) rate reporting
      - STEP equalizer support: transfer some STEP (connection to radio
        on platforms with integrated wifi) related parameters from the
        BIOS to the firmware.

   - Qualcomm 802.11ax WiFi (ath11k):
      - IPQ5018 support
      - Fine Timing Measurement (FTM) responder role support
      - channel 177 support

   - MediaTek WiFi (mt76):
      - per-PHY LED support
      - mt7996: EHT (Wi-Fi 7) support
      - Wireless Ethernet Dispatch (WED) reset support
      - switch to using page pool allocator

   - RealTek WiFi (rtw89):
      - support new version of Bluetooth co-existance

   - Mobile:
      - rmnet: support TX aggregation"

* tag 'net-next-6.3' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next: (1872 commits)
  page_pool: add a comment explaining the fragment counter usage
  net: ethtool: fix __ethtool_dev_mm_supported() implementation
  ethtool: pse-pd: Fix double word in comments
  xsk: add linux/vmalloc.h to xsk.c
  sefltests: netdevsim: wait for devlink instance after netns removal
  selftest: fib_tests: Always cleanup before exit
  net/mlx5e: Align IPsec ASO result memory to be as required by hardware
  net/mlx5e: TC, Set CT miss to the specific ct action instance
  net/mlx5e: Rename CHAIN_TO_REG to MAPPED_OBJ_TO_REG
  net/mlx5: Refactor tc miss handling to a single function
  net/mlx5: Kconfig: Make tc offload depend on tc skb extension
  net/sched: flower: Support hardware miss to tc action
  net/sched: flower: Move filter handle initialization earlier
  net/sched: cls_api: Support hardware miss to tc action
  net/sched: Rename user cookie and act cookie
  sfc: fix builds without CONFIG_RTC_LIB
  sfc: clean up some inconsistent indentings
  net/mlx4_en: Introduce flexible array to silence overflow warning
  net: lan966x: Fix possible deadlock inside PTP
  net/ulp: Remove redundant ->clone() test in inet_clone_ulp().
  ...

1 files changed, 515 insertions, 0 deletions

diff --git a/tools/testing/kunit/kunit.py b/tools/testing/kunit/kunit.py
new file mode 100755
index 000000000..43fbe9631
--- /dev/null
+++ b/tools/testing/kunit/kunit.py
@@ -0,0 +1,515 @@
+#!/usr/bin/env python3
+# SPDX-License-Identifier: GPL-2.0
+#
+# A thin wrapper on top of the KUnit Kernel
+#
+# Copyright (C) 2019, Google LLC.
+# Author: Felix Guo <felixguoxiuping@gmail.com>
+# Author: Brendan Higgins <brendanhiggins@google.com>
+
+import argparse
+import os
+import re
+import shlex
+import sys
+import time
+
+assert sys.version_info >= (3, 7), "Python version is too old"
+
+from dataclasses import dataclass
+from enum import Enum, auto
+from typing import Iterable, List, Optional, Sequence, Tuple
+
+import kunit_json
+import kunit_kernel
+import kunit_parser
+from kunit_printer import stdout
+
+class KunitStatus(Enum):
+	SUCCESS = auto()
+	CONFIG_FAILURE = auto()
+	BUILD_FAILURE = auto()
+	TEST_FAILURE = auto()
+
+@dataclass
+class KunitResult:
+	status: KunitStatus
+	elapsed_time: float
+
+@dataclass
+class KunitConfigRequest:
+	build_dir: str
+	make_options: Optional[List[str]]
+
+@dataclass
+class KunitBuildRequest(KunitConfigRequest):
+	jobs: int
+
+@dataclass
+class KunitParseRequest:
+	raw_output: Optional[str]
+	json: Optional[str]
+
+@dataclass
+class KunitExecRequest(KunitParseRequest):
+	build_dir: str
+	timeout: int
+	filter_glob: str
+	kernel_args: Optional[List[str]]
+	run_isolated: Optional[str]
+
+@dataclass
+class KunitRequest(KunitExecRequest, KunitBuildRequest):
+	pass
+
+
+def get_kernel_root_path() -> str:
+	path = sys.argv[0] if not __file__ else __file__
+	parts = os.path.realpath(path).split('tools/testing/kunit')
+	if len(parts) != 2:
+		sys.exit(1)
+	return parts[0]
+
+def config_tests(linux: kunit_kernel.LinuxSourceTree,
+		 request: KunitConfigRequest) -> KunitResult:
+	stdout.print_with_timestamp('Configuring KUnit Kernel ...')
+
+	config_start = time.time()
+	success = linux.build_reconfig(request.build_dir, request.make_options)
+	config_end = time.time()
+	if not success:
+		return KunitResult(KunitStatus.CONFIG_FAILURE,
+				   config_end - config_start)
+	return KunitResult(KunitStatus.SUCCESS,
+			   config_end - config_start)
+
+def build_tests(linux: kunit_kernel.LinuxSourceTree,
+		request: KunitBuildRequest) -> KunitResult:
+	stdout.print_with_timestamp('Building KUnit Kernel ...')
+
+	build_start = time.time()
+	success = linux.build_kernel(request.jobs,
+				     request.build_dir,
+				     request.make_options)
+	build_end = time.time()
+	if not success:
+		return KunitResult(KunitStatus.BUILD_FAILURE,
+				   build_end - build_start)
+	if not success:
+		return KunitResult(KunitStatus.BUILD_FAILURE,
+				   build_end - build_start)
+	return KunitResult(KunitStatus.SUCCESS,
+			   build_end - build_start)
+
+def config_and_build_tests(linux: kunit_kernel.LinuxSourceTree,
+			   request: KunitBuildRequest) -> KunitResult:
+	config_result = config_tests(linux, request)
+	if config_result.status != KunitStatus.SUCCESS:
+		return config_result
+
+	return build_tests(linux, request)
+
+def _list_tests(linux: kunit_kernel.LinuxSourceTree, request: KunitExecRequest) -> List[str]:
+	args = ['kunit.action=list']
+	if request.kernel_args:
+		args.extend(request.kernel_args)
+
+	output = linux.run_kernel(args=args,
+			   timeout=request.timeout,
+			   filter_glob=request.filter_glob,
+			   build_dir=request.build_dir)
+	lines = kunit_parser.extract_tap_lines(output)
+	# Hack! Drop the dummy TAP version header that the executor prints out.
+	lines.pop()
+
+	# Filter out any extraneous non-test output that might have gotten mixed in.
+	return [l for l in lines if re.match(r'^[^\s.]+\.[^\s.]+$', l)]
+
+def _suites_from_test_list(tests: List[str]) -> List[str]:
+	"""Extracts all the suites from an ordered list of tests."""
+	suites = []  # type: List[str]
+	for t in tests:
+		parts = t.split('.', maxsplit=2)
+		if len(parts) != 2:
+			raise ValueError(f'internal KUnit error, test name should be of the form "<suite>.<test>", got "{t}"')
+		suite, case = parts
+		if not suites or suites[-1] != suite:
+			suites.append(suite)
+	return suites
+
+
+
+def exec_tests(linux: kunit_kernel.LinuxSourceTree, request: KunitExecRequest) -> KunitResult:
+	filter_globs = [request.filter_glob]
+	if request.run_isolated:
+		tests = _list_tests(linux, request)
+		if request.run_isolated == 'test':
+			filter_globs = tests
+		if request.run_isolated == 'suite':
+			filter_globs = _suites_from_test_list(tests)
+			# Apply the test-part of the user's glob, if present.
+			if '.' in request.filter_glob:
+				test_glob = request.filter_glob.split('.', maxsplit=2)[1]
+				filter_globs = [g + '.'+ test_glob for g in filter_globs]
+
+	metadata = kunit_json.Metadata(arch=linux.arch(), build_dir=request.build_dir, def_config='kunit_defconfig')
+
+	test_counts = kunit_parser.TestCounts()
+	exec_time = 0.0
+	for i, filter_glob in enumerate(filter_globs):
+		stdout.print_with_timestamp('Starting KUnit Kernel ({}/{})...'.format(i+1, len(filter_globs)))
+
+		test_start = time.time()
+		run_result = linux.run_kernel(
+			args=request.kernel_args,
+			timeout=request.timeout,
+			filter_glob=filter_glob,
+			build_dir=request.build_dir)
+
+		_, test_result = parse_tests(request, metadata, run_result)
+		# run_kernel() doesn't block on the kernel exiting.
+		# That only happens after we get the last line of output from `run_result`.
+		# So exec_time here actually contains parsing + execution time, which is fine.
+		test_end = time.time()
+		exec_time += test_end - test_start
+
+		test_counts.add_subtest_counts(test_result.counts)
+
+	if len(filter_globs) == 1 and test_counts.crashed > 0:
+		bd = request.build_dir
+		print('The kernel seems to have crashed; you can decode the stack traces with:')
+		print('$ scripts/decode_stacktrace.sh {}/vmlinux {} < {} | tee {}/decoded.log | {} parse'.format(
+				bd, bd, kunit_kernel.get_outfile_path(bd), bd, sys.argv[0]))
+
+	kunit_status = _map_to_overall_status(test_counts.get_status())
+	return KunitResult(status=kunit_status, elapsed_time=exec_time)
+
+def _map_to_overall_status(test_status: kunit_parser.TestStatus) -> KunitStatus:
+	if test_status in (kunit_parser.TestStatus.SUCCESS, kunit_parser.TestStatus.SKIPPED):
+		return KunitStatus.SUCCESS
+	return KunitStatus.TEST_FAILURE
+
+def parse_tests(request: KunitParseRequest, metadata: kunit_json.Metadata, input_data: Iterable[str]) -> Tuple[KunitResult, kunit_parser.Test]:
+	parse_start = time.time()
+
+	if request.raw_output:
+		# Treat unparsed results as one passing test.
+		fake_test = kunit_parser.Test()
+		fake_test.status = kunit_parser.TestStatus.SUCCESS
+		fake_test.counts.passed = 1
+
+		output: Iterable[str] = input_data
+		if request.raw_output == 'all':
+			pass
+		elif request.raw_output == 'kunit':
+			output = kunit_parser.extract_tap_lines(output)
+		for line in output:
+			print(line.rstrip())
+		parse_time = time.time() - parse_start
+		return KunitResult(KunitStatus.SUCCESS, parse_time), fake_test
+
+
+	# Actually parse the test results.
+	test = kunit_parser.parse_run_tests(input_data)
+	parse_time = time.time() - parse_start
+
+	if request.json:
+		json_str = kunit_json.get_json_result(
+					test=test,
+					metadata=metadata)
+		if request.json == 'stdout':
+			print(json_str)
+		else:
+			with open(request.json, 'w') as f:
+				f.write(json_str)
+			stdout.print_with_timestamp("Test results stored in %s" %
+				os.path.abspath(request.json))
+
+	if test.status != kunit_parser.TestStatus.SUCCESS:
+		return KunitResult(KunitStatus.TEST_FAILURE, parse_time), test
+
+	return KunitResult(KunitStatus.SUCCESS, parse_time), test
+
+def run_tests(linux: kunit_kernel.LinuxSourceTree,
+	      request: KunitRequest) -> KunitResult:
+	run_start = time.time()
+
+	config_result = config_tests(linux, request)
+	if config_result.status != KunitStatus.SUCCESS:
+		return config_result
+
+	build_result = build_tests(linux, request)
+	if build_result.status != KunitStatus.SUCCESS:
+		return build_result
+
+	exec_result = exec_tests(linux, request)
+
+	run_end = time.time()
+
+	stdout.print_with_timestamp((
+		'Elapsed time: %.3fs total, %.3fs configuring, %.3fs ' +
+		'building, %.3fs running\n') % (
+				run_end - run_start,
+				config_result.elapsed_time,
+				build_result.elapsed_time,
+				exec_result.elapsed_time))
+	return exec_result
+
+# Problem:
+# $ kunit.py run --json
+# works as one would expect and prints the parsed test results as JSON.
+# $ kunit.py run --json suite_name
+# would *not* pass suite_name as the filter_glob and print as json.
+# argparse will consider it to be another way of writing
+# $ kunit.py run --json=suite_name
+# i.e. it would run all tests, and dump the json to a `suite_name` file.
+# So we hackily automatically rewrite --json => --json=stdout
+pseudo_bool_flag_defaults = {
+		'--json': 'stdout',
+		'--raw_output': 'kunit',
+}
+def massage_argv(argv: Sequence[str]) -> Sequence[str]:
+	def massage_arg(arg: str) -> str:
+		if arg not in pseudo_bool_flag_defaults:
+			return arg
+		return  f'{arg}={pseudo_bool_flag_defaults[arg]}'
+	return list(map(massage_arg, argv))
+
+def get_default_jobs() -> int:
+	return len(os.sched_getaffinity(0))
+
+def add_common_opts(parser) -> None:
+	parser.add_argument('--build_dir',
+			    help='As in the make command, it specifies the build '
+			    'directory.',
+			    type=str, default='.kunit', metavar='DIR')
+	parser.add_argument('--make_options',
+			    help='X=Y make option, can be repeated.',
+			    action='append', metavar='X=Y')
+	parser.add_argument('--alltests',
+			    help='Run all KUnit tests via tools/testing/kunit/configs/all_tests.config',
+			    action='store_true')
+	parser.add_argument('--kunitconfig',
+			     help='Path to Kconfig fragment that enables KUnit tests.'
+			     ' If given a directory, (e.g. lib/kunit), "/.kunitconfig" '
+			     'will get  automatically appended. If repeated, the files '
+			     'blindly concatenated, which might not work in all cases.',
+			     action='append', metavar='PATHS')
+	parser.add_argument('--kconfig_add',
+			     help='Additional Kconfig options to append to the '
+			     '.kunitconfig, e.g. CONFIG_KASAN=y. Can be repeated.',
+			    action='append', metavar='CONFIG_X=Y')
+
+	parser.add_argument('--arch',
+			    help=('Specifies the architecture to run tests under. '
+				  'The architecture specified here must match the '
+				  'string passed to the ARCH make param, '
+				  'e.g. i386, x86_64, arm, um, etc. Non-UML '
+				  'architectures run on QEMU.'),
+			    type=str, default='um', metavar='ARCH')
+
+	parser.add_argument('--cross_compile',
+			    help=('Sets make\'s CROSS_COMPILE variable; it should '
+				  'be set to a toolchain path prefix (the prefix '
+				  'of gcc and other tools in your toolchain, for '
+				  'example `sparc64-linux-gnu-` if you have the '
+				  'sparc toolchain installed on your system, or '
+				  '`$HOME/toolchains/microblaze/gcc-9.2.0-nolibc/microblaze-linux/bin/microblaze-linux-` '
+				  'if you have downloaded the microblaze toolchain '
+				  'from the 0-day website to a directory in your '
+				  'home directory called `toolchains`).'),
+			    metavar='PREFIX')
+
+	parser.add_argument('--qemu_config',
+			    help=('Takes a path to a path to a file containing '
+				  'a QemuArchParams object.'),
+			    type=str, metavar='FILE')
+
+	parser.add_argument('--qemu_args',
+			    help='Additional QEMU arguments, e.g. "-smp 8"',
+			    action='append', metavar='')
+
+def add_build_opts(parser) -> None:
+	parser.add_argument('--jobs',
+			    help='As in the make command, "Specifies  the number of '
+			    'jobs (commands) to run simultaneously."',
+			    type=int, default=get_default_jobs(), metavar='N')
+
+def add_exec_opts(parser) -> None:
+	parser.add_argument('--timeout',
+			    help='maximum number of seconds to allow for all tests '
+			    'to run. This does not include time taken to build the '
+			    'tests.',
+			    type=int,
+			    default=300,
+			    metavar='SECONDS')
+	parser.add_argument('filter_glob',
+			    help='Filter which KUnit test suites/tests run at '
+			    'boot-time, e.g. list* or list*.*del_test',
+			    type=str,
+			    nargs='?',
+			    default='',
+			    metavar='filter_glob')
+	parser.add_argument('--kernel_args',
+			    help='Kernel command-line parameters. Maybe be repeated',
+			     action='append', metavar='')
+	parser.add_argument('--run_isolated', help='If set, boot the kernel for each '
+			    'individual suite/test. This is can be useful for debugging '
+			    'a non-hermetic test, one that might pass/fail based on '
+			    'what ran before it.',
+			    type=str,
+			    choices=['suite', 'test'])
+
+def add_parse_opts(parser) -> None:
+	parser.add_argument('--raw_output', help='If set don\'t parse output from kernel. '
+			    'By default, filters to just KUnit output. Use '
+			    '--raw_output=all to show everything',
+			     type=str, nargs='?', const='all', default=None, choices=['all', 'kunit'])
+	parser.add_argument('--json',
+			    nargs='?',
+			    help='Prints parsed test results as JSON to stdout or a file if '
+			    'a filename is specified. Does nothing if --raw_output is set.',
+			    type=str, const='stdout', default=None, metavar='FILE')
+
+
+def tree_from_args(cli_args: argparse.Namespace) -> kunit_kernel.LinuxSourceTree:
+	"""Returns a LinuxSourceTree based on the user's arguments."""
+	# Allow users to specify multiple arguments in one string, e.g. '-smp 8'
+	qemu_args: List[str] = []
+	if cli_args.qemu_args:
+		for arg in cli_args.qemu_args:
+			qemu_args.extend(shlex.split(arg))
+
+	kunitconfigs = cli_args.kunitconfig if cli_args.kunitconfig else []
+	if cli_args.alltests:
+		# Prepend so user-specified options take prio if we ever allow
+		# --kunitconfig options to have differing options.
+		kunitconfigs = [kunit_kernel.ALL_TESTS_CONFIG_PATH] + kunitconfigs
+
+	return kunit_kernel.LinuxSourceTree(cli_args.build_dir,
+			kunitconfig_paths=kunitconfigs,
+			kconfig_add=cli_args.kconfig_add,
+			arch=cli_args.arch,
+			cross_compile=cli_args.cross_compile,
+			qemu_config_path=cli_args.qemu_config,
+			extra_qemu_args=qemu_args)
+
+
+def main(argv):
+	parser = argparse.ArgumentParser(
+			description='Helps writing and running KUnit tests.')
+	subparser = parser.add_subparsers(dest='subcommand')
+
+	# The 'run' command will config, build, exec, and parse in one go.
+	run_parser = subparser.add_parser('run', help='Runs KUnit tests.')
+	add_common_opts(run_parser)
+	add_build_opts(run_parser)
+	add_exec_opts(run_parser)
+	add_parse_opts(run_parser)
+
+	config_parser = subparser.add_parser('config',
+						help='Ensures that .config contains all of '
+						'the options in .kunitconfig')
+	add_common_opts(config_parser)
+
+	build_parser = subparser.add_parser('build', help='Builds a kernel with KUnit tests')
+	add_common_opts(build_parser)
+	add_build_opts(build_parser)
+
+	exec_parser = subparser.add_parser('exec', help='Run a kernel with KUnit tests')
+	add_common_opts(exec_parser)
+	add_exec_opts(exec_parser)
+	add_parse_opts(exec_parser)
+
+	# The 'parse' option is special, as it doesn't need the kernel source
+	# (therefore there is no need for a build_dir, hence no add_common_opts)
+	# and the '--file' argument is not relevant to 'run', so isn't in
+	# add_parse_opts()
+	parse_parser = subparser.add_parser('parse',
+					    help='Parses KUnit results from a file, '
+					    'and parses formatted results.')
+	add_parse_opts(parse_parser)
+	parse_parser.add_argument('file',
+				  help='Specifies the file to read results from.',
+				  type=str, nargs='?', metavar='input_file')
+
+	cli_args = parser.parse_args(massage_argv(argv))
+
+	if get_kernel_root_path():
+		os.chdir(get_kernel_root_path())
+
+	if cli_args.subcommand == 'run':
+		if not os.path.exists(cli_args.build_dir):
+			os.mkdir(cli_args.build_dir)
+
+		linux = tree_from_args(cli_args)
+		request = KunitRequest(build_dir=cli_args.build_dir,
+				       make_options=cli_args.make_options,
+				       jobs=cli_args.jobs,
+				       raw_output=cli_args.raw_output,
+				       json=cli_args.json,
+				       timeout=cli_args.timeout,
+				       filter_glob=cli_args.filter_glob,
+				       kernel_args=cli_args.kernel_args,
+				       run_isolated=cli_args.run_isolated)
+		result = run_tests(linux, request)
+		if result.status != KunitStatus.SUCCESS:
+			sys.exit(1)
+	elif cli_args.subcommand == 'config':
+		if cli_args.build_dir and (
+				not os.path.exists(cli_args.build_dir)):
+			os.mkdir(cli_args.build_dir)
+
+		linux = tree_from_args(cli_args)
+		request = KunitConfigRequest(build_dir=cli_args.build_dir,
+					     make_options=cli_args.make_options)
+		result = config_tests(linux, request)
+		stdout.print_with_timestamp((
+			'Elapsed time: %.3fs\n') % (
+				result.elapsed_time))
+		if result.status != KunitStatus.SUCCESS:
+			sys.exit(1)
+	elif cli_args.subcommand == 'build':
+		linux = tree_from_args(cli_args)
+		request = KunitBuildRequest(build_dir=cli_args.build_dir,
+					    make_options=cli_args.make_options,
+					    jobs=cli_args.jobs)
+		result = config_and_build_tests(linux, request)
+		stdout.print_with_timestamp((
+			'Elapsed time: %.3fs\n') % (
+				result.elapsed_time))
+		if result.status != KunitStatus.SUCCESS:
+			sys.exit(1)
+	elif cli_args.subcommand == 'exec':
+		linux = tree_from_args(cli_args)
+		exec_request = KunitExecRequest(raw_output=cli_args.raw_output,
+						build_dir=cli_args.build_dir,
+						json=cli_args.json,
+						timeout=cli_args.timeout,
+						filter_glob=cli_args.filter_glob,
+						kernel_args=cli_args.kernel_args,
+						run_isolated=cli_args.run_isolated)
+		result = exec_tests(linux, exec_request)
+		stdout.print_with_timestamp((
+			'Elapsed time: %.3fs\n') % (result.elapsed_time))
+		if result.status != KunitStatus.SUCCESS:
+			sys.exit(1)
+	elif cli_args.subcommand == 'parse':
+		if cli_args.file is None:
+			sys.stdin.reconfigure(errors='backslashreplace')  # pytype: disable=attribute-error
+			kunit_output = sys.stdin
+		else:
+			with open(cli_args.file, 'r', errors='backslashreplace') as f:
+				kunit_output = f.read().splitlines()
+		# We know nothing about how the result was created!
+		metadata = kunit_json.Metadata()
+		request = KunitParseRequest(raw_output=cli_args.raw_output,
+					    json=cli_args.json)
+		result, _ = parse_tests(request, metadata, kunit_output)
+		if result.status != KunitStatus.SUCCESS:
+			sys.exit(1)
+	else:
+		parser.print_help()
+
+if __name__ == '__main__':
+	main(sys.argv[1:])