scripts/gdb/modules: add get module text support

When we get an text address from coredump and we cannot find
this address in vmlinux, it might located in kernel module.

We want to know which kernel module it located in.

This GDB scripts can help us to find the target kernel module.

(gdb) lx-getmod-by-textaddr 0xffff800002d305ac
0xffff800002d305ac is in kasan_test.ko

Link: https://lkml.kernel.org/r/20230808083020.22254-3-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: fix 'lx-lsmod' show the wrong size

'lsmod' shows total core layout size, so we need to sum up all the
sections in core layout in gdb scripts.

/ # lsmod
kasan_test 200704 0 - Live 0xffff80007f640000

Before patch:
(gdb) lx-lsmod
Address Module Size Used by
0xffff80007f640000 kasan_test 36864 0

After patch:
(gdb) lx-lsmod
Address Module Size Used by
0xffff80007f640000 kasan_test 200704 0

Link: https://lkml.kernel.org/r/20230710092852.31049-1-Kuan-Ying.Lee@mediatek.com
Fixes: b4aff7513df3 ("scripts/gdb: use mem instead of core_layout to get the module address")
Signed-off-by: Kuan-Ying Lee <Kuan-Ying.Lee@mediatek.com>
Reviewed-by: Pankaj Raghav <p.raghav@samsung.com>
Cc: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>
Cc: Chinwen Chang <chinwen.chang@mediatek.com>
Cc: Jan Kiszka <jan.kiszka@siemens.com>
Cc: Kieran Bingham <kbingham@kernel.org>
Cc: Luis Chamberlain <mcgrof@kernel.org>
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: use mem instead of core_layout to get the module address

commit ac3b43283923 ("module: replace module_layout with module_memory")
changed the struct module data structure from module_layout to
module_memory. The core_layout member which is used while loading
modules are not available anymore leading to the following error while
running gdb:

(gdb) lx-symbols
loading vmlinux
Python Exception <class 'gdb.error'>: There is no member named core_layout.
Error occurred in Python: There is no member named core_layout.

Replace core_layout with its new counterpart mem[MOD_TEXT].

Fixes: ac3b43283923 ("module: replace module_layout with module_memory")
Signed-off-by: Pankaj Raghav <p.raghav@samsung.com>
Signed-off-by: Luis Chamberlain <mcgrof@kernel.org>

scripts/gdb: support !CONFIG_MODULES gracefully

If CONFIG_MODULES is not enabled, lx-lsmod tries to find a non-existent
symbol and generates an unfriendly traceback:

(gdb) lx-lsmod
Address Module Size Used by
Traceback (most recent call last):
File "scripts/gdb/linux/modules.py", line 75, in invoke
for module in module_list():
File "scripts/gdb/linux/modules.py", line 24, in module_list
module_ptr_type = module_type.get_type().pointer()
File "scripts/gdb/linux/utils.py", line 28, in get_type
self._type = gdb.lookup_type(self._name)
gdb.error: No struct type named module.
Error occurred in Python command: No struct type named module.

Catch the error and return an empty module_list() for a clean command
output as follows:

(gdb) lx-lsmod
Address Module Size Used by
(gdb)

Link: http://lkml.kernel.org/r/94d533819437408b85ae5864f939dd7ca6fbfcd6.1462865983.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: convert modules usage to lists functions

Simplify the module list functions with the new list_for_each_entry
abstractions

Link: http://lkml.kernel.org/r/ad0101c9391088608166fcec26af179868973d86.1462865983.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: Adjust module reference counter reported by lx-lsmod

This takes the MODULE_REF_BASE into account.

Link: http://lkml.kernel.org/r/d926d2d54caa034adb964b52215090cbdb875249.1462865983.git.jan.kiszka@siemens.com
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: account for changes in module data structure

Commit 7523e4dc5057 ("module: use a structure to encapsulate layout.")
factored out the module_layout structure. Adjust the symbol loader and
the lsmod command to this.

Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Reviewed-by: Kieran Bingham <kieran.bingham@linaro.org>
Tested-by: Kieran Bingham <kieran.bingham@linaro.org> (qemu-{ARM,x86})
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: Jiri Kosina <jkosina@suse.cz>
Cc: Jason Wessel <jason.wessel@windriver.com>
Cc: <stable@vger.kernel.org> [4.4+]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

scripts/gdb: fix lx-lsmod refcnt

Commit 2f35c41f58a9 ("module: Replace module_ref with atomic_t refcnt")
changes the way refcnt is handled but did not update the gdb script to
use the new variable.

Since refcnt is not per-cpu anymore, we can directly read its value.

Signed-off-by: Adrien Schildknecht <adrien+dev@schischi.me>
Reviewed-by: Jan Kiszka <jan.kiszka@siemens.com>
Cc: Pantelis Koukousoulas <pktoss@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

scripts/gdb: convert CpuList to generator function

Yet another code simplification.

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: convert ModuleList to generator function

Analogously to the task list, convert the module list to a generator
function. It noticeably simplifies the code.

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: 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 lx-lsmod command

This adds a lsmod-like command to list all currently loaded modules of the
target.

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 internal helper and convenience function to look up a module

Add the internal helper get_module_by_name to obtain the module structure
corresponding to the given name. Also export this service as a
convenience function.

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 module iteration class

Will soon be used for loading symbols, printing global variables or
listing modules.

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>