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Message-ID: <20240806165628.7ceffbe8@imammedo.users.ipa.redhat.com>
Date: Tue, 6 Aug 2024 16:56:28 +0200
From: Igor Mammedov <imammedo@...hat.com>
To: Mauro Carvalho Chehab <mchehab+huawei@...nel.org>
Cc: Jonathan Cameron <Jonathan.Cameron@...wei.com>, Shiju Jose
<shiju.jose@...wei.com>, Cleber Rosa <crosa@...hat.com>, John Snow
<jsnow@...hat.com>, linux-kernel@...r.kernel.org, qemu-devel@...gnu.org
Subject: Re: [PATCH v5 7/7] scripts/ghes_inject: add a script to generate
GHES error inject
On Fri, 2 Aug 2024 23:44:02 +0200
Mauro Carvalho Chehab <mchehab+huawei@...nel.org> wrote:
> Using the QMP GHESv2 API requires preparing a raw data array
> containing a CPER record.
>
> Add a helper script with subcommands to prepare such data.
>
> Currently, only ARM Processor error CPER record is supported.
>
> Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@...nel.org>
> ---
> MAINTAINERS | 3 +
> scripts/arm_processor_error.py | 352 +++++++++++++++++++++++++++++++++
> scripts/ghes_inject.py | 59 ++++++
> scripts/qmp_helper.py | 249 +++++++++++++++++++++++
> 4 files changed, 663 insertions(+)
> create mode 100644 scripts/arm_processor_error.py
> create mode 100755 scripts/ghes_inject.py
> create mode 100644 scripts/qmp_helper.py
>
> diff --git a/MAINTAINERS b/MAINTAINERS
> index 655edcb6688c..e490f69da1de 100644
> --- a/MAINTAINERS
> +++ b/MAINTAINERS
> @@ -2081,6 +2081,9 @@ S: Maintained
> F: hw/arm/ghes_cper.c
> F: hw/acpi/ghes_cper_stub.c
> F: qapi/ghes-cper.json
> +F: scripts/ghes_inject.py
> +F: scripts/arm_processor_error.py
> +F: scripts/qmp_helper.py
>
> ppc4xx
> L: qemu-ppc@...gnu.org
> diff --git a/scripts/arm_processor_error.py b/scripts/arm_processor_error.py
> new file mode 100644
> index 000000000000..df4efa508790
> --- /dev/null
> +++ b/scripts/arm_processor_error.py
> @@ -0,0 +1,352 @@
> +#!/usr/bin/env python3
> +#
> +# pylint: disable=C0301, C0114, R0912, R0913, R0914, R0915, W0511
> +# SPDX-License-Identifier: GPL-2.0
> +#
> +# Copyright (C) 2024 Mauro Carvalho Chehab <mchehab+huawei@...nel.org>
> +
> +# TODO: current implementation has dummy defaults.
> +#
> +# For a better implementation, a QMP addition/call is needed to
> +# retrieve some data for ARM Processor Error injection:
> +#
> +# - machine emulation architecture, as ARM current default is
> +# for AArch64;
> +# - ARM registers: power_state, midr, mpidr.
I'm not really reviewing the script but here some pointers how to fetch properties
start qemu with QMP connection
./qemu-system-aarch64 -M virt -qmp unix:/tmp/s,server,nowait
use script
./scripts/qmp/qom-get --socket /tmp/s /machine/unattached/device[0].midr
you can use ./scripts/qmp/qom-tree to explore what's there
see commit e61cc6b5c69 how to add property (DEFINE_PROP_UINT32 part mainly),
as long as it's prefixed with "x-" (meaning internal/unstable) likelihood is
that no one would object adding extra ones
> +
> +import argparse
> +import json
> +
> +from qmp_helper import (qmp_command, get_choice, get_mult_array,
> + get_mult_choices, get_mult_int, bit,
> + data_add, to_guid)
> +
> +# Arm processor EINJ logic
> +#
> +ACPI_GHES_ARM_CPER_LENGTH = 40
> +ACPI_GHES_ARM_CPER_PEI_LENGTH = 32
> +
> +# TODO: query it from emulation. Current default valid only for Aarch64
> +CONTEXT_AARCH64_EL1 = 5
> +
> +class ArmProcessorEinj:
> + """
> + Implements ARM Processor Error injection via GHES
> + """
> +
> + def __init__(self):
> + """Initialize the error injection class"""
> +
> + # Valid choice values
> + self.arm_valid_bits = {
> + "mpidr": bit(0),
> + "affinity": bit(1),
> + "running": bit(2),
> + "vendor": bit(3),
> + }
> +
> + self.pei_flags = {
> + "first": bit(0),
> + "last": bit(1),
> + "propagated": bit(2),
> + "overflow": bit(3),
> + }
> +
> + self.pei_error_types = {
> + "cache": bit(1),
> + "tlb": bit(2),
> + "bus": bit(3),
> + "micro-arch": bit(4),
> + }
> +
> + self.pei_valid_bits = {
> + "multiple-error": bit(0),
> + "flags": bit(1),
> + "error-info": bit(2),
> + "virt-addr": bit(3),
> + "phy-addr": bit(4),
> + }
> +
> + self.data = bytearray()
> +
> + def create_subparser(self, subparsers):
> + """Add a subparser to handle for the error fields"""
> +
> + parser = subparsers.add_parser("arm",
> + help="Generate an ARM processor CPER")
> +
> + arm_valid_bits = ",".join(self.arm_valid_bits.keys())
> + flags = ",".join(self.pei_flags.keys())
> + error_types = ",".join(self.pei_error_types.keys())
> + pei_valid_bits = ",".join(self.arm_valid_bits.keys())
> +
> + # UEFI N.16 ARM Validation bits
> + g_arm = parser.add_argument_group("ARM processor")
> + g_arm.add_argument("--arm", "--arm-valid",
> + help=f"ARM valid bits: {arm_valid_bits}")
> + g_arm.add_argument("-a", "--affinity", "--level", "--affinity-level",
> + type=lambda x: int(x, 0),
> + help="Affinity level (when multiple levels apply)")
> + g_arm.add_argument("-l", "--mpidr", type=lambda x: int(x, 0),
> + help="Multiprocessor Affinity Register")
> + g_arm.add_argument("-i", "--midr", type=lambda x: int(x, 0),
> + help="Main ID Register")
> + g_arm.add_argument("-r", "--running",
> + action=argparse.BooleanOptionalAction,
> + default=None,
> + help="Indicates if the processor is running or not")
> + g_arm.add_argument("--psci", "--psci-state",
> + type=lambda x: int(x, 0),
> + help="Power State Coordination Interface - PSCI state")
> +
> + # TODO: Add vendor-specific support
> +
> + # UEFI N.17 bitmaps (type and flags)
> + g_pei = parser.add_argument_group("ARM Processor Error Info (PEI)")
> + g_pei.add_argument("-t", "--type", nargs="+",
> + help=f"one or more error types: {error_types}")
> + g_pei.add_argument("-f", "--flags", nargs="*",
> + help=f"zero or more error flags: {flags}")
> + g_pei.add_argument("-V", "--pei-valid", "--error-valid", nargs="*",
> + help=f"zero or more PEI valid bits: {pei_valid_bits}")
> +
> + # UEFI N.17 Integer values
> + g_pei.add_argument("-m", "--multiple-error", nargs="+",
> + help="Number of errors: 0: Single error, 1: Multiple errors, 2-65535: Error count if known")
> + g_pei.add_argument("-e", "--error-info", nargs="+",
> + help="Error information (UEFI 2.10 tables N.18 to N.20)")
> + g_pei.add_argument("-p", "--physical-address", nargs="+",
> + help="Physical address")
> + g_pei.add_argument("-v", "--virtual-address", nargs="+",
> + help="Virtual address")
> +
> + # UEFI N.21 Context
> + g_ctx = parser.add_argument_group("Processor Context")
> + g_ctx.add_argument("--ctx-type", "--context-type", nargs="*",
> + help="Type of the context (0=ARM32 GPR, 5=ARM64 EL1, other values supported)")
> + g_ctx.add_argument("--ctx-size", "--context-size", nargs="*",
> + help="Minimal size of the context")
> + g_ctx.add_argument("--ctx-array", "--context-array", nargs="*",
> + help="Comma-separated arrays for each context")
> +
> + # Vendor-specific data
> + g_vendor = parser.add_argument_group("Vendor-specific data")
> + g_vendor.add_argument("--vendor", "--vendor-specific", nargs="+",
> + help="Vendor-specific byte arrays of data")
> +
> + def parse_args(self, args):
> + """Parse subcommand arguments"""
> +
> + cper = {}
> + pei = {}
> + ctx = {}
> + vendor = {}
> +
> + arg = vars(args)
> +
> + # Handle global parameters
> + if args.arm:
> + arm_valid_init = False
> + cper["valid"] = get_choice(name="valid",
> + value=args.arm,
> + choices=self.arm_valid_bits,
> + suffixes=["-error", "-err"])
> + else:
> + cper["valid"] = 0
> + arm_valid_init = True
> +
> + if "running" in arg:
> + if args.running:
> + cper["running-state"] = bit(0)
> + else:
> + cper["running-state"] = 0
> + else:
> + cper["running-state"] = 0
> +
> + if arm_valid_init:
> + if args.affinity:
> + cper["valid"] |= self.arm_valid_bits["affinity"]
> +
> + if args.mpidr:
> + cper["valid"] |= self.arm_valid_bits["mpidr"]
> +
> + if "running-state" in cper:
> + cper["valid"] |= self.arm_valid_bits["running"]
> +
> + if args.psci:
> + cper["valid"] |= self.arm_valid_bits["running"]
> +
> + # Handle PEI
> + if not args.type:
> + args.type = ["cache-error"]
> +
> + get_mult_choices(
> + pei,
> + name="valid",
> + values=args.pei_valid,
> + choices=self.pei_valid_bits,
> + suffixes=["-valid", "-info", "--information", "--addr"],
> + )
> + get_mult_choices(
> + pei,
> + name="type",
> + values=args.type,
> + choices=self.pei_error_types,
> + suffixes=["-error", "-err"],
> + )
> + get_mult_choices(
> + pei,
> + name="flags",
> + values=args.flags,
> + choices=self.pei_flags,
> + suffixes=["-error", "-cap"],
> + )
> + get_mult_int(pei, "error-info", args.error_info)
> + get_mult_int(pei, "multiple-error", args.multiple_error)
> + get_mult_int(pei, "phy-addr", args.physical_address)
> + get_mult_int(pei, "virt-addr", args.virtual_address)
> +
> + # Handle context
> + get_mult_int(ctx, "type", args.ctx_type, allow_zero=True)
> + get_mult_int(ctx, "minimal-size", args.ctx_size, allow_zero=True)
> + get_mult_array(ctx, "register", args.ctx_array, allow_zero=True)
> +
> + get_mult_array(vendor, "bytes", args.vendor, max_val=255)
> +
> + # Store PEI
> + pei_data = bytearray()
> + default_flags = self.pei_flags["first"]
> + default_flags |= self.pei_flags["last"]
> +
> + error_info_num = 0
> +
> + for i, p in pei.items(): # pylint: disable=W0612
> + error_info_num += 1
> +
> + # UEFI 2.10 doesn't define how to encode error information
> + # when multiple types are raised. So, provide a default only
> + # if a single type is there
> + if "error-info" not in p:
> + if p["type"] == bit(1):
> + p["error-info"] = 0x0091000F
> + if p["type"] == bit(2):
> + p["error-info"] = 0x0054007F
> + if p["type"] == bit(3):
> + p["error-info"] = 0x80D6460FFF
> + if p["type"] == bit(4):
> + p["error-info"] = 0x78DA03FF
> +
> + if "valid" not in p:
> + p["valid"] = 0
> + if "multiple-error" in p:
> + p["valid"] |= self.pei_valid_bits["multiple-error"]
> +
> + if "flags" in p:
> + p["valid"] |= self.pei_valid_bits["flags"]
> +
> + if "error-info" in p:
> + p["valid"] |= self.pei_valid_bits["error-info"]
> +
> + if "phy-addr" in p:
> + p["valid"] |= self.pei_valid_bits["phy-addr"]
> +
> + if "virt-addr" in p:
> + p["valid"] |= self.pei_valid_bits["virt-addr"]
> +
> + # Version
> + data_add(pei_data, 0, 1)
> +
> + data_add(pei_data, ACPI_GHES_ARM_CPER_PEI_LENGTH, 1)
> +
> + data_add(pei_data, p["valid"], 2)
> + data_add(pei_data, p["type"], 1)
> + data_add(pei_data, p.get("multiple-error", 1), 2)
> + data_add(pei_data, p.get("flags", default_flags), 1)
> + data_add(pei_data, p.get("error-info", 0), 8)
> + data_add(pei_data, p.get("virt-addr", 0xDEADBEEF), 8)
> + data_add(pei_data, p.get("phy-addr", 0xABBA0BAD), 8)
> +
> + # Store Context
> + ctx_data = bytearray()
> + context_info_num = 0
> +
> + if ctx:
> + for k in sorted(ctx.keys()):
> + context_info_num += 1
> +
> + if "type" not in ctx:
> + ctx[k]["type"] = CONTEXT_AARCH64_EL1
> +
> + if "register" not in ctx:
> + ctx[k]["register"] = []
> +
> + reg_size = len(ctx[k]["register"])
> + size = 0
> +
> + if "minimal-size" in ctx:
> + size = ctx[k]["minimal-size"]
> +
> + size = max(size, reg_size)
> +
> + size = (size + 1) % 0xFFFE
> +
> + # Version
> + data_add(ctx_data, 0, 2)
> +
> + data_add(ctx_data, ctx[k]["type"], 2)
> +
> + data_add(ctx_data, 8 * size, 4)
> +
> + for r in ctx[k]["register"]:
> + data_add(ctx_data, r, 8)
> +
> + for i in range(reg_size, size): # pylint: disable=W0612
> + data_add(ctx_data, 0, 8)
> +
> + # Vendor-specific bytes are not grouped
> + vendor_data = bytearray()
> + if vendor:
> + for k in sorted(vendor.keys()):
> + for b in vendor[k]["bytes"]:
> + data_add(vendor_data, b, 1)
> +
> + # Encode ARM Processor Error
> + data = bytearray()
> +
> + data_add(data, cper["valid"], 4)
> +
> + data_add(data, error_info_num, 2)
> + data_add(data, context_info_num, 2)
> +
> + # Calculate the length of the CPER data
> + cper_length = ACPI_GHES_ARM_CPER_LENGTH
> + cper_length += len(pei_data)
> + cper_length += len(vendor_data)
> + cper_length += len(ctx_data)
> + data_add(data, cper_length, 4)
> +
> + data_add(data, arg.get("affinity-level", 0), 1)
> +
> + # Reserved
> + data_add(data, 0, 3)
> +
> + data_add(data, arg.get("mpidr-el1", 0), 8)
> + data_add(data, arg.get("midr-el1", 0), 8)
> + data_add(data, cper["running-state"], 4)
> + data_add(data, arg.get("psci-state", 0), 4)
> +
> + # Add PEI
> + data.extend(pei_data)
> + data.extend(ctx_data)
> + data.extend(vendor_data)
> +
> + self.data = data
> +
> + def run(self, host, port):
> + """Execute QMP commands"""
> +
> + guid = to_guid(0xE19E3D16, 0xBC11, 0x11E4,
> + [0x9C, 0xAA, 0xC2, 0x05,
> + 0x1D, 0x5D, 0x46, 0xB0])
> +
> + qmp_command(host, port, guid, self.data)
> diff --git a/scripts/ghes_inject.py b/scripts/ghes_inject.py
> new file mode 100755
> index 000000000000..8415ccbbc53d
> --- /dev/null
> +++ b/scripts/ghes_inject.py
> @@ -0,0 +1,59 @@
> +#!/usr/bin/env python3
> +#
> +# pylint: disable=C0301, C0114
> +# SPDX-License-Identifier: GPL-2.0
> +#
> +# Copyright (C) 2024 Mauro Carvalho Chehab <mchehab+huawei@...nel.org>
> +
> +import argparse
> +
> +from arm_processor_error import ArmProcessorEinj
> +
> +EINJ_DESCRIPTION = """
> +Handle ACPI GHESv2 error injection logic QEMU QMP interface.\n
> +
> +It allows using UEFI BIOS EINJ features to generate GHES records.
> +
> +It helps testing Linux CPER and GHES drivers and to test rasdaemon
> +error handling logic.
> +
> +Currently, it support ARM processor error injection for ARM processor
> +events, being compatible with UEFI 2.9A Errata.
> +
> +This small utility works together with those QEMU additions:
> +- https://gitlab.com/mchehab_kernel/qemu/-/tree/arm-error-inject-v2
> +"""
> +
> +def main():
> + """Main program"""
> +
> + # Main parser - handle generic args like QEMU QMP TCP socket options
> + parser = argparse.ArgumentParser(prog="einj.py",
> + formatter_class=argparse.RawDescriptionHelpFormatter,
> + usage="%(prog)s [options]",
> + description=EINJ_DESCRIPTION,
> + epilog="If a field is not defined, a default value will be applied by QEMU.")
> +
> + g_options = parser.add_argument_group("QEMU QMP socket options")
> + g_options.add_argument("-H", "--host", default="localhost", type=str,
> + help="host name")
> + g_options.add_argument("-P", "--port", default=4445, type=int,
> + help="TCP port number")
> +
> + arm_einj = ArmProcessorEinj()
> +
> + # Call subparsers
> + subparsers = parser.add_subparsers(dest='command')
> +
> + arm_einj.create_subparser(subparsers)
> +
> + args = parser.parse_args()
> +
> + # Handle subparser commands
> + if args.command == "arm":
> + arm_einj.parse_args(args)
> + arm_einj.run(args.host, args.port)
> +
> +
> +if __name__ == "__main__":
> + main()
> diff --git a/scripts/qmp_helper.py b/scripts/qmp_helper.py
> new file mode 100644
> index 000000000000..13fae7a7af0e
> --- /dev/null
> +++ b/scripts/qmp_helper.py
> @@ -0,0 +1,249 @@
> +#!/usr/bin/env python3
> +#
> +# pylint: disable=C0301, C0114, R0912, R0913, R0915, W0511
> +# SPDX-License-Identifier: GPL-2.0
> +#
> +# Copyright (C) 2024 Mauro Carvalho Chehab <mchehab+huawei@...nel.org>
> +
> +import json
> +import socket
> +import sys
> +
> +from base64 import b64encode
> +
> +#
> +# Socket QMP send command
> +#
> +def qmp_command(host, port, guid, data):
> + """Send commands to QEMU though QMP TCP socket"""
> +
> + # Fill the commands to be sent
> + commands = []
> +
> + # Needed to negotiate QMP and for QEMU to accept the command
> + commands.append('{ "execute": "qmp_capabilities" } ')
> +
> + base64_data = b64encode(bytes(data)).decode('ascii')
> +
> + cmd_arg = {
> + 'cper': {
> + 'notification-type': guid,
> + "raw-data": base64_data
> + }
> + }
> +
> + command = '{ "execute": "ghes-cper", '
> + command += '"arguments": ' + json.dumps(cmd_arg) + " }"
> +
> + commands.append(command)
> +
> + s = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
> + try:
> + s.connect((host, port))
> + except ConnectionRefusedError:
> + sys.exit(f"Can't connect to QMP host {host}:{port}")
> +
> + data = s.recv(1024)
> + try:
> + obj = json.loads(data.decode("utf-8"))
> + except json.JSONDecodeError as e:
> + print(f"Invalid QMP answer: {e}")
> + s.close()
> + return
> +
> + if "QMP" not in obj:
> + print(f"Invalid QMP answer: {data.decode("utf-8")}")
> + s.close()
> + return
> +
> + for i, command in enumerate(commands):
> + s.sendall(command.encode("utf-8"))
> + data = s.recv(1024)
> + try:
> + obj = json.loads(data.decode("utf-8"))
> + except json.JSONDecodeError as e:
> + print(f"Invalid QMP answer: {e}")
> + s.close()
> + return
> +
> + if isinstance(obj.get("return"), dict):
> + if obj["return"]:
> + print(json.dumps(obj["return"]))
> + elif i > 0:
> + print("Error injected.")
> + elif isinstance(obj.get("error"), dict):
> + error = obj["error"]
> + print(f'{error["class"]}: {error["desc"]}')
> + else:
> + print(json.dumps(obj))
> +
> + s.shutdown(socket.SHUT_WR)
> + while 1:
> + data = s.recv(1024)
> + if data == b"":
> + break
> + try:
> + obj = json.loads(data.decode("utf-8"))
> + except json.JSONDecodeError as e:
> + print(f"Invalid QMP answer: {e}")
> + s.close()
> + return
> +
> + if isinstance(obj.get("return"), dict):
> + print(json.dumps(obj["return"]))
> + if isinstance(obj.get("error"), dict):
> + error = obj["error"]
> + print(f'{error["class"]}: {error["desc"]}')
> + else:
> + print(json.dumps(obj))
> +
> + s.close()
> +
> +
> +#
> +# Helper routines to handle multiple choice arguments
> +#
> +def get_choice(name, value, choices, suffixes=None):
> + """Produce a list from multiple choice argument"""
> +
> + new_values = 0
> +
> + if not value:
> + return new_values
> +
> + for val in value.split(","):
> + val = val.lower()
> +
> + if suffixes:
> + for suffix in suffixes:
> + val = val.removesuffix(suffix)
> +
> + if val not in choices.keys():
> + sys.exit(f"Error on '{name}': choice {val} is invalid.")
> +
> + val = choices[val]
> +
> + new_values |= val
> +
> + return new_values
> +
> +
> +def get_mult_array(mult, name, values, allow_zero=False, max_val=None):
> + """Add numbered hashes from integer lists"""
> +
> + if not allow_zero:
> + if not values:
> + return
> + else:
> + if values is None:
> + return
> +
> + if not values:
> + i = 0
> + if i not in mult:
> + mult[i] = {}
> +
> + mult[i][name] = []
> + return
> +
> + i = 0
> + for value in values:
> + for val in value.split(","):
> + try:
> + val = int(val, 0)
> + except ValueError:
> + sys.exit(f"Error on '{name}': {val} is not an integer")
> +
> + if val < 0:
> + sys.exit(f"Error on '{name}': {val} is not unsigned")
> +
> + if max_val and val > max_val:
> + sys.exit(f"Error on '{name}': {val} is too little")
> +
> + if i not in mult:
> + mult[i] = {}
> +
> + if name not in mult[i]:
> + mult[i][name] = []
> +
> + mult[i][name].append(val)
> +
> + i += 1
> +
> +
> +def get_mult_choices(mult, name, values, choices,
> + suffixes=None, allow_zero=False):
> + """Add numbered hashes from multiple choice arguments"""
> +
> + if not allow_zero:
> + if not values:
> + return
> + else:
> + if values is None:
> + return
> +
> + i = 0
> + for val in values:
> + new_values = get_choice(name, val, choices, suffixes)
> +
> + if i not in mult:
> + mult[i] = {}
> +
> + mult[i][name] = new_values
> + i += 1
> +
> +
> +def get_mult_int(mult, name, values, allow_zero=False):
> + """Add numbered hashes from integer arguments"""
> + if not allow_zero:
> + if not values:
> + return
> + else:
> + if values is None:
> + return
> +
> + i = 0
> + for val in values:
> + try:
> + val = int(val, 0)
> + except ValueError:
> + sys.exit(f"Error on '{name}': {val} is not an integer")
> +
> + if val < 0:
> + sys.exit(f"Error on '{name}': {val} is not unsigned")
> +
> + if i not in mult:
> + mult[i] = {}
> +
> + mult[i][name] = val
> + i += 1
> +
> +
> +#
> +# Data encode helper functions
> +#
> +def bit(b):
> + """Simple macro to define a bit on a bitmask"""
> + return 1 << b
> +
> +
> +def data_add(data, value, num_bytes):
> + """Adds bytes from value inside a bitarray"""
> +
> + data.extend(value.to_bytes(num_bytes, byteorder="little"))
> +
> +def to_guid(time_low, time_mid, time_high, nodes):
> + """Create an GUID string"""
> +
> + assert(len(nodes) == 8)
> +
> + clock = nodes[0] << 8 | nodes[1]
> +
> + node = 0
> + for i in range(2, len(nodes)):
> + node = node << 8 | nodes[i]
> +
> + s = f"{time_low:08x}-{time_mid:04x}-"
> + s += f"{time_high:04x}-{clock:04x}-{node:012x}"
> +
> + return s
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