linux-toradex.git/drivers/misc/lkdtm/Makefile, branch master

lkdtm/powerpc: add PPC_RADIX_TLBIEL test for radix MCE validation

2026-05-21T10:21:01+00:00

Add a new LKDTM trigger (PPC_RADIX_TLBIEL) that executes a process-scoped
radix TLBIEL instruction to exercise the radix MMU behaviour and
associated machine check exception (MCE) handling paths.

This provides a way to validate MCE handling in radix mode. Currently,
there is no dedicated LKDTM test that exercises this path or allows
triggering radix-specific machine check behaviour for validation.

The test is only enabled on ppc64 systems with radix MMU
support and If radix is not active, the trigger is skipped and reported as
XFAIL.

Co-developed-by: Ritesh Harjani (IBM) 
Signed-off-by: Ritesh Harjani (IBM) 
Signed-off-by: Sayali Patil 
Reviewed-by: Ritesh Harjani (IBM) 
Reviewed-by: Michael Ellerman 
Link: https://patch.msgid.link/85c9b59217bcecb3c7af52e9d5b175266771d7de.1778975974.git.sayalip@linux.ibm.com
Signed-off-by: Kees Cook

stackleak: Rename STACKLEAK to KSTACK_ERASE

2025-07-22T04:35:01+00:00

In preparation for adding Clang sanitizer coverage stack depth tracking
that can support stack depth callbacks:

- Add the new top-level CONFIG_KSTACK_ERASE option which will be
  implemented either with the stackleak GCC plugin, or with the Clang
  stack depth callback support.
- Rename CONFIG_GCC_PLUGIN_STACKLEAK as needed to CONFIG_KSTACK_ERASE,
  but keep it for anything specific to the GCC plugin itself.
- Rename all exposed "STACKLEAK" names and files to "KSTACK_ERASE" (named
  for what it does rather than what it protects against), but leave as
  many of the internals alone as possible to avoid even more churn.

While here, also split "prev_lowest_stack" into CONFIG_KSTACK_ERASE_METRICS,
since that's the only place it is referenced from.

Suggested-by: Ingo Molnar 
Link: https://lore.kernel.org/r/20250717232519.2984886-1-kees@kernel.org
Signed-off-by: Kees Cook

Merge tag 'kbuild-v6.10' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild

2024-05-18T19:39:20+00:00

Pull Kbuild updates from Masahiro Yamada:

 - Avoid 'constexpr', which is a keyword in C23

 - Allow 'dtbs_check' and 'dt_compatible_check' run independently of
   'dt_binding_check'

 - Fix weak references to avoid GOT entries in position-independent code
   generation

 - Convert the last use of 'optional' property in arch/sh/Kconfig

 - Remove support for the 'optional' property in Kconfig

 - Remove support for Clang's ThinLTO caching, which does not work with
   the .incbin directive

 - Change the semantics of $(src) so it always points to the source
   directory, which fixes Makefile inconsistencies between upstream and
   downstream

 - Fix 'make tar-pkg' for RISC-V to produce a consistent package

 - Provide reasonable default coverage for objtool, sanitizers, and
   profilers

 - Remove redundant OBJECT_FILES_NON_STANDARD, KASAN_SANITIZE, etc.

 - Remove the last use of tristate choice in drivers/rapidio/Kconfig

 - Various cleanups and fixes in Kconfig

* tag 'kbuild-v6.10' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild: (46 commits)
  kconfig: use sym_get_choice_menu() in sym_check_prop()
  rapidio: remove choice for enumeration
  kconfig: lxdialog: remove initialization with A_NORMAL
  kconfig: m/nconf: merge two item_add_str() calls
  kconfig: m/nconf: remove dead code to display value of bool choice
  kconfig: m/nconf: remove dead code to display children of choice members
  kconfig: gconf: show checkbox for choice correctly
  kbuild: use GCOV_PROFILE and KCSAN_SANITIZE in scripts/Makefile.modfinal
  Makefile: remove redundant tool coverage variables
  kbuild: provide reasonable defaults for tool coverage
  modules: Drop the .export_symbol section from the final modules
  kconfig: use menu_list_for_each_sym() in sym_check_choice_deps()
  kconfig: use sym_get_choice_menu() in conf_write_defconfig()
  kconfig: add sym_get_choice_menu() helper
  kconfig: turn defaults and additional prompt for choice members into error
  kconfig: turn missing prompt for choice members into error
  kconfig: turn conf_choice() into void function
  kconfig: use linked list in sym_set_changed()
  kconfig: gconf: use MENU_CHANGED instead of SYMBOL_CHANGED
  kconfig: gconf: remove debug code
  ...

Makefile: remove redundant tool coverage variables

2024-05-14T14:35:48+00:00

Now Kbuild provides reasonable defaults for objtool, sanitizers, and
profilers.

Remove redundant variables.

Note:

This commit changes the coverage for some objects:

  - include arch/mips/vdso/vdso-image.o into UBSAN, GCOV, KCOV
  - include arch/sparc/vdso/vdso-image-*.o into UBSAN
  - include arch/sparc/vdso/vma.o into UBSAN
  - include arch/x86/entry/vdso/extable.o into KASAN, KCSAN, UBSAN, GCOV, KCOV
  - include arch/x86/entry/vdso/vdso-image-*.o into KASAN, KCSAN, UBSAN, GCOV, KCOV
  - include arch/x86/entry/vdso/vdso32-setup.o into KASAN, KCSAN, UBSAN, GCOV, KCOV
  - include arch/x86/entry/vdso/vma.o into GCOV, KCOV
  - include arch/x86/um/vdso/vma.o into KASAN, GCOV, KCOV

I believe these are positive effects because all of them are kernel
space objects.

Signed-off-by: Masahiro Yamada 
Reviewed-by: Kees Cook 
Tested-by: Roberto Sassu

lkdtm: Disable CFI checking for perms functions

2024-05-01T19:37:42+00:00

The EXEC_RODATA test plays a lot of tricks to live in the .rodata section,
and once again ran into objtool's (completely reasonable) assumptions
that executable code should live in an executable section. However, this
manifested only under CONFIG_CFI_CLANG=y, as one of the .cfi_sites was
pointing into the .rodata section.

Since we're testing non-CFI execution properties in perms.c (and
rodata.c), we can disable CFI for the involved functions, and remove the
CFI arguments from rodata.c entirely.

Reported-by: kernel test robot 
Closes: https://lore.kernel.org/oe-lkp/202308301532.d7acf63e-oliver.sang@intel.com
Fixes: 6342a20efbd8 ("objtool: Add elf_create_section_pair()")
Link: https://lore.kernel.org/r/20240430234953.work.760-kees@kernel.org
Signed-off-by: Kees Cook

lkdtm: Disable return thunks in rodata.c

2022-07-20T17:24:53+00:00

The following warning was seen:

  WARNING: CPU: 0 PID: 0 at arch/x86/kernel/alternative.c:557 apply_returns (arch/x86/kernel/alternative.c:557 (discriminator 1))
  Modules linked in:
  CPU: 0 PID: 0 Comm: swapper/0 Not tainted 5.19.0-rc4-00008-gee88d363d156 #1
  Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.16.0-debian-1.16.0-4 04/01/2014
  RIP: 0010:apply_returns (arch/x86/kernel/alternative.c:557 (discriminator 1))
  Code: ff ff 74 cb 48 83 c5 04 49 39 ee 0f 87 81 fe ff ff e9 22 ff ff ff 0f 0b 48 83 c5 04 49 39 ee 0f 87 6d fe ff ff e9 0e ff ff ff <0f> 0b 48 83 c5 04 49 39 ee 0f 87 59 fe ff ff e9 fa fe ff ff 48 89

The warning happened when apply_returns() failed to convert "JMP
__x86_return_thunk" to RET.  It was instead a JMP to nowhere, due to the
thunk relocation not getting resolved.

That rodata.o code is objcopy'd to .rodata, and later memcpy'd, so
relocations don't work (and are apparently silently ignored).

LKDTM is only used for testing, so the naked RET should be fine.  So
just disable return thunks for that file.

While at it, disable objtool and KCSAN for the file.

Fixes: 0b53c374b9ef ("x86/retpoline: Use -mfunction-return")
Reported-by: kernel test robot 
Debugged-by: Peter Zijlstra 
Signed-off-by: Josh Poimboeuf 
Signed-off-by: Peter Zijlstra (Intel) 
Link: https://lore.kernel.org/lkml/Ys58BxHxoDZ7rfpr@xsang-OptiPlex-9020/

Merge tag 'char-misc-5.17-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc

2022-01-14T15:02:28+00:00

Pull char/misc and other driver updates from Greg KH:
 "Here is the large set of char, misc, and other "small" driver
  subsystem changes for 5.17-rc1.

  Lots of different things are in here for char/misc drivers such as:

   - habanalabs driver updates

   - mei driver updates

   - lkdtm driver updates

   - vmw_vmci driver updates

   - android binder driver updates

   - other small char/misc driver updates

  Also smaller driver subsystems have also been updated, including:

   - fpga subsystem updates

   - iio subsystem updates

   - soundwire subsystem updates

   - extcon subsystem updates

   - gnss subsystem updates

   - phy subsystem updates

   - coresight subsystem updates

   - firmware subsystem updates

   - comedi subsystem updates

   - mhi subsystem updates

   - speakup subsystem updates

   - rapidio subsystem updates

   - spmi subsystem updates

   - virtual driver updates

   - counter subsystem updates

  Too many individual changes to summarize, the shortlog contains the
  full details.

  All of these have been in linux-next for a while with no reported
  issues"

* tag 'char-misc-5.17-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc: (406 commits)
  counter: 104-quad-8: Fix use-after-free by quad8_irq_handler
  dt-bindings: mux: Document mux-states property
  dt-bindings: ti-serdes-mux: Add defines for J721S2 SoC
  counter: remove old and now unused registration API
  counter: ti-eqep: Convert to new counter registration
  counter: stm32-lptimer-cnt: Convert to new counter registration
  counter: stm32-timer-cnt: Convert to new counter registration
  counter: microchip-tcb-capture: Convert to new counter registration
  counter: ftm-quaddec: Convert to new counter registration
  counter: intel-qep: Convert to new counter registration
  counter: interrupt-cnt: Convert to new counter registration
  counter: 104-quad-8: Convert to new counter registration
  counter: Update documentation for new counter registration functions
  counter: Provide alternative counter registration functions
  counter: stm32-timer-cnt: Convert to counter_priv() wrapper
  counter: stm32-lptimer-cnt: Convert to counter_priv() wrapper
  counter: ti-eqep: Convert to counter_priv() wrapper
  counter: ftm-quaddec: Convert to counter_priv() wrapper
  counter: intel-qep: Convert to counter_priv() wrapper
  counter: microchip-tcb-capture: Convert to counter_priv() wrapper
  ...

lkdtm: Fix content of section containing lkdtm_rodata_do_nothing()

2021-12-16T23:54:37+00:00

On a kernel without CONFIG_STRICT_KERNEL_RWX, running EXEC_RODATA
test leads to "Illegal instruction" failure.

Looking at the content of rodata_objcopy.o, we see that the
function content zeroes only:

	Disassembly of section .rodata:

	0000000000000000 <.lkdtm_rodata_do_nothing>:
	   0:	00 00 00 00 	.long 0x0

Add the contents flag in order to keep the content of the section
while renaming it.

	Disassembly of section .rodata:

	0000000000000000 <.lkdtm_rodata_do_nothing>:
	   0:	4e 80 00 20 	blr

Fixes: e9e08a07385e ("lkdtm: support llvm-objcopy")
Cc: stable@vger.kernel.org
Cc: Kees Cook 
Cc: Arnd Bergmann 
Cc: Greg Kroah-Hartman 
Cc: Nick Desaulniers 
Cc: Nathan Chancellor 
Signed-off-by: Christophe Leroy 
Reviewed-by: Nick Desaulniers 
Signed-off-by: Kees Cook 
Link: https://lore.kernel.org/r/8900731fbc05fb8b0de18af7133a8fc07c3c53a1.1633712176.git.christophe.leroy@csgroup.eu

powerpc/64s: Make hash MMU support configurable

2021-12-09T11:40:24+00:00

This adds Kconfig selection which allows 64s hash MMU support to be
disabled. It can be disabled if radix support is enabled, the minimum
supported CPU type is POWER9 (or higher), and KVM is not selected.

Signed-off-by: Nicholas Piggin 
Signed-off-by: Michael Ellerman 
Link: https://lore.kernel.org/r/20211201144153.2456614-17-npiggin@gmail.com

drivers/misc/lkdtm: disable LTO for rodata.o

2021-01-14T16:21:09+00:00

Disable LTO for rodata.o to allow objcopy to be used to
manipulate sections.

Signed-off-by: Sami Tolvanen 
Acked-by: Kees Cook 
Signed-off-by: Kees Cook 
Link: https://lore.kernel.org/r/20201211184633.3213045-14-samitolvanen@google.com