From 90cf83dbd2f08dd0513cd9f19155878c55acb445 Mon Sep 17 00:00:00 2001 From: Stephen Boyd Date: Tue, 14 May 2019 15:45:53 -0700 Subject: scripts/gdb: add kernel config dumping command lx-configdump dumps the contents of the gzipped .config to a text file when the config is included in the kernel with CONFIG_IKCONFIG. By default, the file written is called config.txt, but it can be any user supplied filename as well. If the kernel config is in a module (configs.ko), then it can be loaded along with symbols for the module loaded with 'lx-symbols' and then this command will still work. Obviously if you have the whole vmlinux then this can also be achieved with scripts/extract-ikconfig, but this gdb script can be useful to confirm that the memory contents of the config in memory and the vmlinux contents on disk match what is expected. [swboyd@chromium.org: v2] Link: http://lkml.kernel.org/r/20190329220844.38234-3-swboyd@chromium.org Link: http://lkml.kernel.org/r/20190325184522.260535-3-swboyd@chromium.org Signed-off-by: Stephen Boyd Cc: Douglas Anderson Cc: Nikolay Borisov Cc: Kieran Bingham Cc: Jan Kiszka Cc: Jackie Liu Cc: Jason Wessel Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- scripts/gdb/linux/config.py | 44 ++++++++++++++++++++++++++++++++++++++++++++ scripts/gdb/vmlinux-gdb.py | 1 + 2 files changed, 45 insertions(+) create mode 100644 scripts/gdb/linux/config.py diff --git a/scripts/gdb/linux/config.py b/scripts/gdb/linux/config.py new file mode 100644 index 000000000000..90e1565b1967 --- /dev/null +++ b/scripts/gdb/linux/config.py @@ -0,0 +1,44 @@ +# SPDX-License-Identifier: GPL-2.0 +# +# Copyright 2019 Google LLC. + +import gdb +import zlib + +from linux import utils + + +class LxConfigDump(gdb.Command): + """Output kernel config to the filename specified as the command + argument. Equivalent to 'zcat /proc/config.gz > config.txt' on + a running target""" + + def __init__(self): + super(LxConfigDump, self).__init__("lx-configdump", gdb.COMMAND_DATA, + gdb.COMPLETE_FILENAME) + + def invoke(self, arg, from_tty): + if len(arg) == 0: + filename = "config.txt" + else: + filename = arg + + try: + py_config_ptr = gdb.parse_and_eval("kernel_config_data + 8") + py_config_size = gdb.parse_and_eval( + "sizeof(kernel_config_data) - 1 - 8 * 2") + except gdb.error as e: + raise gdb.GdbError("Can't find config, enable CONFIG_IKCONFIG?") + + inf = gdb.inferiors()[0] + zconfig_buf = utils.read_memoryview(inf, py_config_ptr, + py_config_size).tobytes() + + config_buf = zlib.decompress(zconfig_buf, 16) + with open(filename, 'wb') as f: + f.write(config_buf) + + gdb.write("Dumped config to " + filename + "\n") + + +LxConfigDump() diff --git a/scripts/gdb/vmlinux-gdb.py b/scripts/gdb/vmlinux-gdb.py index 6e0b0afd888a..be0efb5dda5b 100644 --- a/scripts/gdb/vmlinux-gdb.py +++ b/scripts/gdb/vmlinux-gdb.py @@ -27,6 +27,7 @@ else: import linux.modules import linux.dmesg import linux.tasks + import linux.config import linux.cpus import linux.lists import linux.proc -- cgit v1.2.3