scripts/gdb/linux/config.py

   1 # SPDX-License-Identifier: GPL-2.0
   2 #
   3 # Copyright 2019 Google LLC.
   4
   5 import gdb
   6 import zlib
   7
   8 from linux import utils
   9
  10
  11 class LxConfigDump(gdb.Command):
  12     """Output kernel config to the filename specified as the command
  13        argument. Equivalent to 'zcat /proc/config.gz > config.txt' on
  14        a running target"""
  15
  16     def __init__(self):
  17         super(LxConfigDump, self).__init__("lx-configdump", gdb.COMMAND_DATA,
  18                                            gdb.COMPLETE_FILENAME)
  19
  20     def invoke(self, arg, from_tty):
  21         if len(arg) == 0:
  22             filename = "config.txt"
  23         else:
  24             filename = arg
  25
  26         try:
  27             py_config_ptr = gdb.parse_and_eval("kernel_config_data + 8")
  28             py_config_size = gdb.parse_and_eval(
  29                     "sizeof(kernel_config_data) - 1 - 8 * 2")
  30         except gdb.error as e:
  31             raise gdb.GdbError("Can't find config, enable CONFIG_IKCONFIG?")
  32
  33         inf = gdb.inferiors()[0]
  34         zconfig_buf = utils.read_memoryview(inf, py_config_ptr,
  35                                             py_config_size).tobytes()
  36
  37         config_buf = zlib.decompress(zconfig_buf, 16)
  38         with open(filename, 'wb') as f:
  39             f.write(config_buf)
  40
  41         gdb.write("Dumped config to " + filename + "\n")
  42
  43
  44 LxConfigDump()