306862167d
The extra is defined to be zero-filled. |
||
---|---|---|
drgn | ||
examples/kernel | ||
scripts | ||
tests | ||
.gitignore | ||
COPYING | ||
README.md | ||
setup.py |
drgn
drgn
is a debugger-as-a-library. It can be used to write Python programs
which use the types and data of the program being debugged.
drgn
was developed for debugging the Linux kernel (as an alternative to the
crash
utility). Currently, it only supports debugging the kernel, but in the
future it will support debugging userspace programs, as well.
Installation
drgn
is built with setuptools. Build it like so:
$ python3 setup.py build_ext -i
Then, you can either run it locally:
$ python3 -m drgn.cli --help
Or install it and run it:
$ sudo python3 setup.py install
$ drgn --help
Or, pick your favorite Python package installation method.
Getting Started
To debug the running kernel, run sudo drgn -k
. drgn
has an interactive mode
and a script mode. If no arguments are passed, drgn
runs in interactive mode;
otherwise, the given script is run with the given arguments. drgn
is actually
just the Python interpreter initialized with a prog
object representing the
debugged program:
$ sudo drgn -k
>>> prog.type('struct list_head')
struct list_head {
struct list_head *next;
struct list_head *prev;
}
>>> prog['modules']
(struct list_head){
.next = (struct list_head *)0xffffffffc0b91048,
.prev = (struct list_head *)0xffffffffc0066148,
}
>>> prog['init_task'].pid
(pid_t)0
>>> from drgn.helpers.kernel import list_for_each_entry
>>> for mod in list_for_each_entry('struct module', prog['modules'].address_of_(), 'list'):
... if mod.refcnt.counter > 10:
... print(mod.name)
...
(char [56])"snd"
(char [56])"evdev"
(char [56])"i915"
See the in-program documentation in interactive mode with help(drgn)
for more
information. See examples
and drgn/helpers/kernel
for some examples.
License
Copyright 2018 - Omar Sandoval Licensed under the GPLv3 or later
Acknowledgements
drgn
is so named because dragons eat dwarves. It is
also named after a song.