lsi-decode-loginfo.py

#!/usr/bin/env python3

import sys
import re

"""
Decode kernel message from mpt*sas, like:
  mpt3sas_cm0: log_info(0x31120303): originator(PL), code(0x12), sub_code(0x0303)
  mpt2sas_cm0: log_info(0x31120303): originator(PL), code(0x12), sub_code(0x0303)

This script does a bitwise AND between the error code and the #defines in the LSI driver header file
It returns the text code and the bitmask for the code

Usage: ./lsi-decode-loginfo.py 0x31120303
"""

# This code originated from https://gist.github.com/azat/e370bae012c05c983c798131cee0c846
# Revised 8/2019 RichardFoo
#
# Tip: The specific error code shown here is commonly associated with a cable fault and is
# accompanied by very slow performance and occasional application-level I/O errors


def get_consts():
    res = []

    # Can be executed cross-platform by fetching the
    # following file and pointing open() to it:
    # https://elixir.bootlin.com/linux/v5.3-rc2/source/drivers/message/fusion/lsi/mpi_log_sas.h
    # It's from the latest Linux kernel, but the file
    # doesn't appear to have changed in 10 years.
    with open("/usr/src/linux/drivers/message/fusion/lsi/mpi_log_sas.h") as f:

        for line in f:
            # Parse the #define lines into the tag and value
            m = re.match(r'^#define[\s]+(?P<name>[0-9a-zA-Z_]+)[\s]+(?:\(|)(?P<value>[0-9a-fA-Fx]+)(?:\)|)$', line)
            if not m:
                continue

            name = m.group('name')

            if name == 'IOC_LOGINFO_CODE_SHIFT':
                continue

            if 'COMPAT_' in name:
                continue

            res.append({
                'name': m.group('name'),
                'value': int(m.group('value'), 16),
                'valueHex': m.group('value'),
            })
    return res


def main():
    if len(sys.argv) != 2:
        print('\nSee comments in code for usage syntax.\n')
        quit()

    # Read the error code from the command-line
    val = int(sys.argv[1], 16)

    print()
    print(sys.argv[1], '= Error code being matched\n')
    for c in get_consts():
        compare = (val & c['value'])
        # Output if the code is a full bitwise match
        if compare and compare == c['value']:
            print(c['valueHex'], c['name'])
    print()

if __name__ == '__main__':
    main()

This looks like it'd be very useful, but I can't quite figure out how to give it what it wants. Can you provide a usage example?

@azat - thanks for this script! It came in handy for a troubleshooting session. I've made some edits to the code, but apparently gist doesn't support pull requests, so... https://gist.github.com/RichardFoo/8784f760f4abb8a4c6ac10ce63f5710d

@RichardFoo applied, thanks!