scripts/gdb/utils: add common type usage

Since we often use 'unsigned long', 'size_t', 'usigned int'
and 'struct page', we add these common types to utils.

Link: https://lkml.kernel.org/r/20230808083020.22254-4-Kuan-Ying.Lee@mediatek.com
Signed-off-by: Kuan-Ying Lee <Kuan-Ying.Lee@mediatek.com>
Cc: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>
Cc: Chinwen Chang <chinwen.chang@mediatek.com>
Cc: Matthias Brugger <matthias.bgg@gmail.com>
Cc: Qun-Wei Lin <qun-wei.lin@mediatek.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

scripts/gdb: create linux/vfs.py for VFS related GDB helpers

Patch series "GDB VFS utils".

I've created a couple GDB convenience functions that I found useful when
debugging some VFS issues and figure others might find them useful. For
instance, they are useful in setting conditional breakpoints on VFS
functions where you only care if the dentry path is a certain value. I
took the opportunity to create a new "vfs" python module to give VFS
related utilities a home.


This patch (of 2):

This will allow for more VFS specific GDB helpers to be collected in one
place. Move utils.dentry_name into the vfs modules. Also a local
variable in proc.py was changed from vfs to mnt to prevent a naming
collision with the new vfs module.

[akpm@linux-foundation.org: add SPDX-License-Identifier]
Link: https://lkml.kernel.org/r/cover.1677631565.git.development@efficientek.com
Link: https://lkml.kernel.org/r/7bba4c065a8c2c47f1fc5b03a7278005b04db251.1677631565.git.development@efficientek.com
Signed-off-by: Glenn Washburn <development@efficientek.com>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Cc: Antonio Borneo <antonio.borneo@foss.st.com>
Cc: Jan Kiszka <jan.kiszka@siemens.com>
Cc: John Ogness <john.ogness@linutronix.de>
Cc: Kieran Bingham <kbingham@kernel.org>
Cc: Petr Mladek <pmladek@suse.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

scripts/gdb: fix lx-timerlist for Python3

Below incompatibilities between Python2 and Python3 made lx-timerlist fail
to run under Python3.

o xrange() is replaced by range() in Python3
o bytes and str are different types in Python3
o the return value of Inferior.read_memory() is memoryview object in
Python3

akpm: cc stable so that older kernels are properly debuggable under newer
Python.

Link: https://lkml.kernel.org/r/TYCP286MB2146EE1180A4D5176CBA8AB2C6819@TYCP286MB2146.JPNP286.PROD.OUTLOOK.COM
Signed-off-by: Peng Liu <liupeng17@lenovo.com>
Reviewed-by: Jan Kiszka <jan.kiszka@siemens.com>
Cc: Florian Fainelli <f.fainelli@gmail.com>
Cc: Kieran Bingham <kbingham@kernel.org>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

scripts/gdb: fix 'lx-dmesg' on 32 bits arch

The type atomic_long_t can have size 4 or 8 bytes, depending on
CONFIG_64BIT; it's only content, the field 'counter', is either an
int or a s64 value.

Current code incorrectly uses the fixed size utils.read_u64() to
read the field 'counter' inside atomic_long_t.

On 32 bits architectures reading the last element 'tail_id' of the
struct prb_desc_ring:
struct prb_desc_ring {
...
atomic_long_t tail_id;
};
causes the utils.read_u64() to access outside the boundary of the
struct and the gdb command 'lx-dmesg' exits with error:
Python Exception <class 'IndexError'>: index out of range
Error occurred in Python: index out of range

Query the really used atomic_long_t counter type size.

Link: https://lore.kernel.org/r/20220617143758.137307-1-antonio.borneo@foss.st.com
Fixes: e60768311af8 ("scripts/gdb: update for lockless printk ringbuffer")
Signed-off-by: Antonio Borneo <antonio.borneo@foss.st.com>
[pmladek@suse.com: Query the really used atomic_long_t counter type size]
Tested-by: Antonio Borneo <antonio.borneo@foss.st.com>
Reviewed-by: John Ogness <john.ogness@linutronix.de>
Signed-off-by: Petr Mladek <pmladek@suse.com>
Link: https://lore.kernel.org/r/20220719122831.19890-1-pmladek@suse.com

scripts/gdb: add utils.read_ulong()

Add a function for reading unsigned long values, which vary in size
depending on the architecture.

Signed-off-by: John Ogness <john.ogness@linutronix.de>
Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
Tested-by: Nick Desaulniers <ndesaulniers@google.com>
Tested-by: Petr Mladek <pmladek@suse.com>
Signed-off-by: Petr Mladek <pmladek@suse.com>
Link: https://lore.kernel.org/r/20200814212525.6118-2-john.ogness@linutronix.de

scripts/gdb: fix lx-dmesg when CONFIG_PRINTK_CALLER is set

When CONFIG_PRINTK_CALLER is set, struct printk_log contains an
additional member caller_id. This affects the offset of the log text.
Account for this by using the type information from gdb to determine all
the offsets instead of using hardcoded values.

This fixes following error:

(gdb) lx-dmesg
Python Exception <class 'ValueError'> embedded null character:
Error occurred in Python command: embedded null character

The read_u* utility functions now take an offset argument to make them
easier to use.

Link: http://lkml.kernel.org/r/20191011142500.2339-1-joel.colledge@linbit.com
Signed-off-by: Joel Colledge <joel.colledge@linbit.com>
Reviewed-by: Jan Kiszka <jan.kiszka@siemens.com>
Cc: Kieran Bingham <kbingham@kernel.org>
Cc: Leonard Crestez <leonard.crestez@nxp.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

scripts/gdb: silence pep8 checks

These scripts have some pep8 style warnings. Fix them up so that this
directory is all pep8 clean.

Link: http://lkml.kernel.org/r/20190329220844.38234-6-swboyd@chromium.org
Signed-off-by: Stephen Boyd <swboyd@chromium.org>
Cc: Douglas Anderson <dianders@chromium.org>
Cc: Nikolay Borisov <n.borisov.lkml@gmail.com>
Cc: Kieran Bingham <kbingham@kernel.org>
Cc: Jan Kiszka <jan.kiszka@siemens.com>
Cc: Jackie Liu <liuyun01@kylinos.cn>
Cc: Jason Wessel <jason.wessel@windriver.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

scripts/gdb: improve types abstraction for gdb python scripts

Change the read_u16 function so it accepts both 'str' and 'byte' as type
for the arguments.

When calling read_memory() from gdb API, depending on if it was built
with 2.7 or 3.X, the format used to return the data will differ ( 'str'
for 2.7, and 'byte' for 3.X ).

Add a function read_memoryview() to be able to get a 'memoryview' object
back from read_memory() both with python 2.7 and 3.X .

Tested with python 3.4 and 2.7
Tested with gdb 7.7

Link: http://lkml.kernel.org/r/73621f564503137a002a639d174e4fb35f73f462.1462865983.git.jan.kiszka@siemens.com
Signed-off-by: Dom Cote <buzdelabuz2+git@gmail.com>
Tested-by: Kieran Bingham <kieran@bingham.xyz> (Py2.7,Py3.4,GDB10)
Signed-off-by: Kieran Bingham <kieran@bingham.xyz>
Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

scripts/gdb: provide a dentry_name VFS path helper

Walk the VFS entries, pre-pending the iname strings to generate a full
VFS path name from a dentry.

Link: http://lkml.kernel.org/r/4328fdb2d15ba7f1b21ad21c2eecc38d9cfc4d13.1462865983.git.jan.kiszka@siemens.com
Signed-off-by: Kieran Bingham <kieran.bingham@linaro.org>
Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

scripts/gdb: provide exception catching parser

If we attempt to read a value that is not available to GDB, an exception
is raised. Most of the time, this is a good thing; however on occasion
we will want to be able to determine if a symbol is available.

By catching the exception to simply return None, we can determine if we
tried to read an invalid value, without the exception taking our
execution context away from us

Link: http://lkml.kernel.org/r/c72b25c06fc66e1d68371154097e2cbb112555d8.1462865983.git.jan.kiszka@siemens.com
Signed-off-by: Kieran Bingham <kieran.bingham@linaro.org>
Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

scripts/gdb: fix PEP8 compliance

Signed-off-by: Thiébaud Weksteen <thiebaud@weksteen.fr>
Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

scripts/gdb: fix typo in exception name

Signed-off-by: Thiébaud Weksteen <thiebaud@weksteen.fr>
Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

scripts/gdb: port to python3 / gdb7.7

I tried to use these scripts in an ubuntu 14.04 host (gdb 7.7 compiled
against python 3.3) but there were several errors.

I believe this patch fixes these issues so that the commands now work (I
tested lx-symbols, lx-dmesg, lx-lsmod).

Main issues that needed to be resolved:

* In python 2 iterators have a "next()" method. In python 3 it is
__next__() instead (so let's just add both).

* In older python versions there was an implicit conversion
in object.__format__() (used when an object is in string.format())
where it was converting the object to str first and then
calling str's __format__(). This has now been removed so
we must explicitly convert to str the objects for which
we need to keep this behavior.

* In dmesg.py: in python 3 log_buf is now a "memoryview" object
which needs to be converted to a string in order to use string
methods like "splitlines()". Luckily memoryview exists in
python 2.7.6 as well, so we can convert log_buf to memoryview
and use the same code in both python 2 and python 3.

This version of the patch has now been tested with gdb 7.7 and both python
3.4 and python 2.7.6 (I think asking for at least python 2.7.6 is a
reasonable requirement instead of complicating the code with version
checks etc).

Signed-off-by: Pantelis Koukousoulas <pktoss@gmail.com>
Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Jason Wessel <jason.wessel@windriver.com>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: Ben Widawsky <ben@bwidawsk.net>
Cc: Borislav Petkov <bp@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

scripts/gdb: add get_gdbserver_type helper

This helper probes the type of the gdb server. Supported are QEMU and
KGDB so far. Knowledge about the gdb server is required e.g. to
retrieve the current CPU or current task.

Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Jason Wessel <jason.wessel@windriver.com>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: Ben Widawsky <ben@bwidawsk.net>
Cc: Borislav Petkov <bp@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

scripts/gdb: add is_target_arch helper

This helper caches to result of "show architecture" and matches the
provided arch (sub-)string against that output.

Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Jason Wessel <jason.wessel@windriver.com>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: Ben Widawsky <ben@bwidawsk.net>
Cc: Borislav Petkov <bp@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

scripts/gdb: add read_u16/32/64 helpers

Add helpers for reading integers from target memory buffers. Required
when caching the memory access is more efficient than reading individual
values via gdb.

Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Jason Wessel <jason.wessel@windriver.com>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: Ben Widawsky <ben@bwidawsk.net>
Cc: Borislav Petkov <bp@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

scripts/gdb: add get_target_endianness helper

Parse the target endianness from the output of "show endian" and cache the
result to return it via the new helper get_target_endiannes. We will need
it for reading integers from buffers that contain target memory.

Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Jason Wessel <jason.wessel@windriver.com>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: Ben Widawsky <ben@bwidawsk.net>
Cc: Borislav Petkov <bp@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

scripts/gdb: add container_of helper and convenience function

Provide an internal helper with container_of semantics. As type lookups
are very slow in gdb-python and we need a type "long" for this, cache the
reference to this type object. Then export the helper also as a
convenience function form use at the gdb command line.

Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Jason Wessel <jason.wessel@windriver.com>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: Ben Widawsky <ben@bwidawsk.net>
Cc: Borislav Petkov <bp@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

scripts/gdb: add cache for type objects

Type lookups are very slow in gdb-python which is often noticeable when
iterating over a number of objects. Introduce the helper class CachedType
that keeps a reference to a gdb.Type object but also refreshes it after an
object file has been loaded.

Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Jason Wessel <jason.wessel@windriver.com>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: Ben Widawsky <ben@bwidawsk.net>
Cc: Borislav Petkov <bp@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>