## gdb helper commands and functions for Linux kernel debugging##  module tools## Copyright (c) Siemens AG, 2013## Authors:#  Jan Kiszka <jan.kiszka@siemens.com>## This work is licensed under the terms of the GNU GPL version 2.# import gdb from linux import cpus, utils, lists  module_type = utils.CachedType("struct module")  def module_list():    global module_type    modules = utils.gdb_eval_or_none("modules")    if modules is None:        return     module_ptr_type = module_type.get_type().pointer()     for module in lists.list_for_each_entry(modules, module_ptr_type, "list"):        yield module  def find_module_by_name(name):    for module in module_list():        if module['name'].string() == name:            return module    return None  class LxModule(gdb.Function):    """Find module by name and return the module variable. $lx_module("MODULE"): Given the name MODULE, iterate over all loaded modulesof the target and return that module variable which MODULE matches."""     def __init__(self):        super(LxModule, self).__init__("lx_module")     def invoke(self, mod_name):        mod_name = mod_name.string()        module = find_module_by_name(mod_name)        if module:            return module.dereference()        else:            raise gdb.GdbError("Unable to find MODULE " + mod_name)  LxModule()  class LxLsmod(gdb.Command):    """List currently loaded modules."""     _module_use_type = utils.CachedType("struct module_use")     def __init__(self):        super(LxLsmod, self).__init__("lx-lsmod", gdb.COMMAND_DATA)     def invoke(self, arg, from_tty):        gdb.write(            "Address{0}    Module                  Size  Used by\n".format(                "        " if utils.get_long_type().sizeof == 8 else ""))         for module in module_list():            layout = module['core_layout']            gdb.write("{address} {name:<19} {size:>8}  {ref}".format(                address=str(layout['base']).split()[0],                name=module['name'].string(),                size=str(layout['size']),                ref=str(module['refcnt']['counter'] - 1)))             t = self._module_use_type.get_type().pointer()            first = True            sources = module['source_list']            for use in lists.list_for_each_entry(sources, t, "source_list"):                gdb.write("{separator}{name}".format(                    separator=" " if first else ",",                    name=use['source']['name'].string()))                first = False             gdb.write("\n")  LxLsmod()