Pull non-MM updates from Andrew Morton:

 - An extensive rework of kexec and crash Kconfig from Eric DeVolder
   ("refactor Kconfig to consolidate KEXEC and CRASH options")

 - kernel.h slimming work from Andy Shevchenko ("kernel.h: Split out a
   couple of macros to args.h")

 - gdb feature work from Kuan-Ying Lee ("Add GDB memory helper
   commands")

 - vsprintf inclusion rationalization from Andy Shevchenko
   ("lib/vsprintf: Rework header inclusions")

 - Switch the handling of kdump from a udev scheme to in-kernel
   handling, by Eric DeVolder ("crash: Kernel handling of CPU and memory
   hot un/plug")

 - Many singleton patches to various parts of the tree

* tag 'mm-nonmm-stable-2023-08-28-22-48' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (81 commits)
  document while_each_thread(), change first_tid() to use for_each_thread()
  drivers/char/mem.c: shrink character device's devlist[] array
  x86/crash: optimize CPU changes
  crash: change crash_prepare_elf64_headers() to for_each_possible_cpu()
  crash: hotplug support for kexec_load()
  x86/crash: add x86 crash hotplug support
  crash: memory and CPU hotplug sysfs attributes
  kexec: exclude elfcorehdr from the segment digest
  crash: add generic infrastructure for crash hotplug support
  crash: move a few code bits to setup support of crash hotplug
  kstrtox: consistently use _tolower()
  kill do_each_thread()
  nilfs2: fix WARNING in mark_buffer_dirty due to discarded buffer reuse
  scripts/bloat-o-meter: count weak symbol sizes
  treewide: drop CONFIG_EMBEDDED
  lockdep: fix static memory detection even more
  lib/vsprintf: declare no_hash_pointers in sprintf.h
  lib/vsprintf: split out sprintf() and friends
  kernel/fork: stop playing lockless games for exe_file replacement
  adfs: delete unused "union adfs_dirtail" definition
  ...

Patch series "kernel.h: Split out a couple of macros to args.h", v4.

There are macros in kernel.h that can be used outside of that header. 
Split them to args.h and replace open coded variants.


This patch (of 4):

kernel.h is being used as a dump for all kinds of stuff for a long time. 
The COUNT_ARGS() and CONCATENATE() macros may be used in some places
without need of the full kernel.h dependency train with it.

Here is the attempt on cleaning it up by splitting out these macros().

While at it, include new header where it's being used.

Link: https://lkml.kernel.org/r/20230718211147.18647-1-andriy.shevchenko@linux.intel.com
Link: https://lkml.kernel.org/r/20230718211147.18647-2-andriy.shevchenko@linux.intel.com
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Acked-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Cc: Bjorn Helgaas <bhelgaas@google.com>
Acked-by: Bjorn Helgaas <bhelgaas@google.com>	[PCI]
Cc: Brendan Higgins <brendan.higgins@linux.dev>
Cc: Daniel Latypov <dlatypov@google.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: David Gow <davidgow@google.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Lorenzo Pieralisi <lpieralisi@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Cc: Shuah Khan <skhan@linuxfoundation.org>
Cc: Sudeep Holla <sudeep.holla@arm.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

External tools, e.g., Intel GPU tools (IGT), support execution of
individual selftests provided by kernel modules.  That could be also
applicable to kunit test modules if they provided test filtering.  But
test filtering is now possible only when kunit code is built into the
kernel.  Moreover, a filter can be specified only at boot time, then
reboot is required each time a different filter is needed.

Build the test filtering code also when kunit is configured as a module,
expose test filtering functions to other kunit source files, and use them
in kunit module notifier callback functions.  Userspace can then reload
the kunit module with a value of the filter_glob parameter tuned to a
specific kunit test module every time it wants to limit the scope of tests
executed on that module load.  Make the kunit.filter* parameters visible
in sysfs for user convenience.

v5: Refresh on tpp of attributes filtering fix
v4: Refresh on top of newly applied attributes patches and changes
    introdced by new versions of other patches submitted in series with
    this one.
v3: Fix CONFIG_GLOB, required by filtering functions, not selected when
    building as a module (lkp@intel.com).
v2: Fix new name of a structure moved to kunit namespace not updated
    across all uses (lkp@intel.com).

Signed-off-by: Janusz Krzysztofik <janusz.krzysztofik@linux.intel.com>
Reviewed-by: David Gow <davidgow@google.com>
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>

Results from kunit tests reported via dmesg may be interleaved with other
kernel messages.  When parsing dmesg for modular kunit results in real
time, external tools, e.g., Intel GPU tools (IGT), may want to insert
their own test name markers into dmesg at the start of each test, before
any kernel message related to that test appears there, so existing upper
level test result parsers have no doubt which test to blame for a specific
kernel message.  Unfortunately, kunit reports names of tests only at their
completion (with the exeption of a not standarized "# Subtest: <name>"
header above a test plan of each test suite or parametrized test).

External tools could be able to insert their own "start of the test"
markers with test names included if they new those names in advance.
Test names could be learned from a list if provided by a kunit test
module.

There exists a feature of listing kunit tests without actually executing
them, but it is now limited to configurations with the kunit module built
in and covers only built-in tests, already available at boot time.
Moreover, switching from list to normal mode requires reboot.  If that
feature was also available when kunit is built as a module, userspace
could load the module with action=list parameter, load some kunit test
modules they are interested in and learn about the list of tests provided
by those modules, then unload them, reload the kunit module in normal mode
and execute the tests with their lists already known.

Extend kunit module notifier initialization callback with a processing
path for only listing the tests provided by a module if the kunit action
parameter is set to "list" or "list_attr".  For user convenience, make the
kunit.action parameter visible in sysfs.

v2: Don't use a different format, use kunit_exec_list_tests() (Rae),
  - refresh on top of new attributes patches, handle newly introduced
    kunit.action=list_attr case (Rae).

Signed-off-by: Janusz Krzysztofik <janusz.krzysztofik@linux.intel.com>
Cc: Rae Moar <rmoar@google.com>
Reviewed-by: David Gow <davidgow@google.com>
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>

According to KTAP specification[1], results should always start from a
header that provides a TAP protocol version, followed by a test plan with
a count of items to be executed.  That pattern should be followed at each
nesting level.  In the current implementation of the top-most, i.e., test
suite level, those rules apply only for test suites built into the kernel,
executed and reported on boot.  Results submitted to dmesg from kunit test
modules loaded later are missing those top-level headers.

As a consequence, if a kunit test module provides more than one test suite
then, without the top level test plan, external tools that are parsing
dmesg for kunit test output are not able to tell how many test suites
should be expected and whether to continue parsing after complete output
from the first test suite is collected.

Submit the top-level headers also from the kunit test module notifier
initialization callback.

v3: Fix new name of a structure moved to kunit namespace not updated in
    executor_test functions (lkp@intel.com).
v2: Use kunit_exec_run_tests() (Mauro, Rae), but prevent it from
    emitting the headers when called on load of non-test modules.

[1] https://docs.kernel.org/dev-tools/ktap.html#

Signed-off-by: Janusz Krzysztofik <janusz.krzysztofik@linux.intel.com>
Cc: Mauro Carvalho Chehab <mchehab@kernel.org>
Cc: Rae Moar <rmoar@google.com>
Reviewed-by: Rae Moar <rmoar@google.com>
Reviewed-by: David Gow <davidgow@google.com>
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>

Add module attribute to the test attribute API. This attribute stores the
module name associated with the test using KBUILD_MODNAME.

The name of a test suite and the module name often do not match. A
reference to the module name associated with the suite could be extremely
helpful in running tests as modules without needing to check the codebase.

This attribute will be printed for each suite.

Reviewed-by: David Gow <davidgow@google.com>
Signed-off-by: Rae Moar <rmoar@google.com>
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>

Add speed attribute to the test attribute API. This attribute will allow
users to mark tests with a category of speed.

Currently the categories of speed proposed are: normal, slow, and very_slow
(outlined in enum kunit_speed). These are outlined in the enum kunit_speed.

The assumed default speed for tests is "normal". This indicates that the
test takes a relatively trivial amount of time (less than 1 second),
regardless of the machine it is running on. Any test slower than this could
be marked as "slow" or "very_slow".

Add the macro KUNIT_CASE_SLOW to set a test as slow, as this is likely a
common use of the attributes API.

Add an example of marking a slow test to kunit-example-test.c.

Reviewed-by: David Gow <davidgow@google.com>
Signed-off-by: Rae Moar <rmoar@google.com>
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>

Add the basic structure of the test attribute API to KUnit, which can be
used to save and access test associated data.

Add attributes.c and attributes.h to hold associated structs and functions
for the API.

Create a struct that holds a variety of associated helper functions for
each test attribute. These helper functions will be used to get the
attribute value, convert the value to a string, and filter based on the
value. This struct is flexible by design to allow for attributes of
numerous types and contexts.

Add a method to print test attributes in the format of "# [<test_name if
not suite>.]<attribute_name>: <attribute_value>".

Example for a suite: "# speed: slow"

Example for a test case: "# test_case.speed: very_slow"

Use this method to report attributes in the KTAP output (KTAP spec:
https://docs.kernel.org/dev-tools/ktap.html) and _list_tests output when
kernel's new kunit.action=list_attr option is used. Note this is derivative
of the kunit.action=list option.

In test.h, add fields and associated helper functions to test cases and
suites to hold user-inputted test attributes.

Reviewed-by: David Gow <davidgow@google.com>
Signed-off-by: Rae Moar <rmoar@google.com>
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>

KUnit aborts the current thread when an assertion fails. Currently, this
is done conditionally as part of the kunit_do_failed_assertion()
function, but this hides the kunit_abort() call from the compiler
(particularly if it's in another module). This, in turn, can lead to
both suboptimal code generation (the compiler can't know if
kunit_do_failed_assertion() will return), and to static analysis tools
like smatch giving false positives.

Moving the kunit_abort() call into the macro should give the compiler
and tools a better chance at understanding what's going on. Doing so
requires exporting kunit_abort(), though it's recommended to continue to
use assertions in lieu of aborting directly.

In addition, kunit_abort() and kunit_do_failed_assertion() are renamed
to make it clear they they're intended for internal KUnit use, to:
__kunit_do_failed_assertion() and __kunit_abort()

Suggested-by: Dan Carpenter <dan.carpenter@linaro.org>
Signed-off-by: David Gow <davidgow@google.com>
Reviewed-by: Miguel Ojeda <ojeda@kernel.org>
Reviewed-by: Daniel Latypov <dlatypov@google.com>
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>

There is no need use opaque test_or_suite pointer and is_test flag
as we don't use anything from the suite struct. Always expect test
pointer and use NULL as indication that provided results are from
the suite so we can treat them differently.

Since results could be from nested tests, like parameterized tests,
add explicit level parameter to properly indent output messages and
thus allow to reuse this function from other places.

While around, remove small code duplication near skip directive.

Signed-off-by: Michal Wajdeczko <michal.wajdeczko@intel.com>
Cc: David Gow <davidgow@google.com>
Cc: Rae Moar <rmoar@google.com>
Reviewed-by: David Gow <davidgow@google.com>
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>