From 119e9db233ad0f4cbd4cfb9f9385a7bca378b37d Mon Sep 17 00:00:00 2001 From: Zeng Chi Date: Mon, 21 Sep 2026 18:24:42 +0800 Subject: KVM: Don't pre-reserve xarray entries when storing empty/NULL attributes Skip the xarray reservation loop when clearing all memory attributes, as storing NULL only erases the entry and never needs to allocate, so no reservation (and no cleanup of a failed one) is required in that case. Suggested-by: Sean Christopherson Cc: David Ballesteros Signed-off-by: Zeng Chi Link: https://patch.msgid.link/20260921102442.1232375-1-zeng_chi911@163.com [sean: split to separate patch] Signed-off-by: Sean Christopherson --- scripts/update-intel-ucode-defs.py | 130 +++++++++++++++++++++++++++++++++++++ 1 file changed, 130 insertions(+) create mode 100755 scripts/update-intel-ucode-defs.py (limited to 'scripts/update-intel-ucode-defs.py') diff --git a/scripts/update-intel-ucode-defs.py b/scripts/update-intel-ucode-defs.py new file mode 100755 index 000000000..9d6cc2c60 --- /dev/null +++ b/scripts/update-intel-ucode-defs.py @@ -0,0 +1,130 @@ +#!/usr/bin/env python3 +# SPDX-License-Identifier: GPL-2.0 +import argparse +import re +import shutil +import subprocess +import sys +import os + +script = os.path.relpath(__file__) + +DESCRIPTION = f""" +For Intel CPUs, update the microcode revisions that determine +X86_BUG_OLD_MICROCODE. + +This script is intended to be run in response to releases of the +official Intel microcode GitHub repository: +https://github.com/intel/Intel-Linux-Processor-Microcode-Data-Files.git + +It takes the Intel microcode files as input and uses iucode-tool to +extract the revision information. It prints the output in the format +expected by intel-ucode-defs.h. + +Usage: + ./{script} /path/to/microcode/files > /path/to/intel-ucode-defs.h + +Typically, someone at Intel would see a new public release, wait for at +least three months to ensure the update is stable, run this script to +refresh the intel-ucode-defs.h file, and send a patch upstream to update +the mainline and stable versions. + +Any exception to this process should be supported with an appropriate +justification. +""" + +SIG_RE = re.compile(r'sig (0x[0-9a-fA-F]+)') +PFM_RE = re.compile(r'pf_mask (0x[0-9a-fA-F]+)') +REV_RE = re.compile(r'rev (0x[0-9a-fA-F]+)') + +# Functions to extract family, model, and stepping +def bits(val, bottom, top): + mask = (1 << (top + 1 - bottom)) - 1 + return (val >> bottom) & mask + +def family(sig): + if bits(sig, 8, 11) == 0xf: + return bits(sig, 8, 11) + bits(sig, 20, 27) + return bits(sig, 8, 11) + +def model(sig): + return bits(sig, 4, 7) | (bits(sig, 16, 19) << 4) + +def step(sig): + return bits(sig, 0, 3) + +class Ucode: + def __init__(self, sig, pfm, rev): + self.family = family(sig) + self.model = model(sig) + self.steppings = 1 << step(sig) + self.platforms = pfm + self.rev = rev + + self.key = (self.family, self.model, self.steppings, self.platforms) + + def __eq__(self, other): + return self.key == other.key + + def __hash__(self): + return hash(self.key) + + def __str__(self): + return "{ .flags = X86_CPU_ID_FLAG_ENTRY_VALID, .vendor = X86_VENDOR_INTEL, .family = 0x%x, .model = 0x%02x, .steppings = 0x%04x, .platform_mask = 0x%02x, .driver_data = 0x%x }," % \ + (self.family, self.model, self.steppings, self.platforms, self.rev) + +def main(): + parser = argparse.ArgumentParser(description=DESCRIPTION, + formatter_class=argparse.RawDescriptionHelpFormatter) + parser.add_argument('ucode_files', nargs='+', help='Path(s) to the microcode files') + + args = parser.parse_args() + + # Process the microcode files using iucode-tool + iucode_tool = shutil.which("iucode-tool") or shutil.which("iucode_tool") + if iucode_tool is None: + print("Error: iucode-tool not found, please install it", file=sys.stderr) + sys.exit(1) + + cmd = [iucode_tool, '--list-all'] + args.ucode_files + + result = subprocess.run(cmd, capture_output=True, text=True) + if result.returncode != 0: + print("Error: iucode-tool ran into an error, exiting", file=sys.stderr) + if result.stderr: + print(result.stderr, file=sys.stderr, end='') + sys.exit(1) + + ucodes = set() + + # Parse the output of iucode-tool + for line in result.stdout.splitlines(): + sig_match = SIG_RE.search(line) + pfm_match = PFM_RE.search(line) + rev_match = REV_RE.search(line) + + if not (sig_match and pfm_match and rev_match): + continue + + sig = int(sig_match.group(1), 16) + pfm = int(pfm_match.group(1), 16) + rev = int(rev_match.group(1), 16) + debug_rev = bits(rev, 31, 31) + if debug_rev != 0: + print("Error: Debug ucode file found, exiting", file=sys.stderr) + sys.exit(1) + + ucodes.add(Ucode(sig, pfm, rev)) + + if not ucodes: + print("Error: No valid microcode files found, exiting", file=sys.stderr) + sys.exit(1) + + # Sort and print the microcode entries + print("/* SPDX-License-Identifier: GPL-2.0 */") + print("/* Auto-generated by scripts/update-intel-ucode-defs.py */") + for u in sorted(ucodes, key=lambda x: x.key): + print(u) + +if __name__ == "__main__": + main() -- cgit v1.3.1