linux-toradex.git/tools/testing/selftests/x86/Makefile, branch master

selftests/x86: Add selftests include path for kselftest.h after centralization

2026-01-17T11:22:27+00:00

The previous change centralizing kselftest.h include path in lib.mk caused x86
selftests to fail, as x86 Makefile overwrites CFLAGS using ":=", dropping the
include path added in lib.mk. Therefore, helpers.h could not find kselftest.h
during compilation.

Fix this by adding the tools/testing/sefltest to CFLAGS in x86 Makefile.

  [ bp: Correct commit ID in Fixes: ]

Fixes: e6fbd1759c9e ("selftests: complete kselftest include centralization")
Closes: https://lore.kernel.org/lkml/CA+G9fYvKjQcCBMfXA-z2YuL2L+3Qd-pJjEUDX8PDdz2-EEQd=Q@mail.gmail.com/T/#m83fd330231287fc9d6c921155bee16c591db7360
Reported-by: Linux Kernel Functional Testing 
Signed-off-by: Bala-Vignesh-Reddy 
Signed-off-by: Borislav Petkov (AMD) 
Tested-by: Anders Roxell 
Tested-by: Brendan Jackman 
Link: https://patch.msgid.link/20251022062948.162852-1-reddybalavignesh9979@gmail.com

selftests/x86: Add a test to detect infinite SIGTRAP handler loop

2025-06-09T15:52:06+00:00

When FRED is enabled, if the Trap Flag (TF) is set without an external
debugger attached, it can lead to an infinite loop in the SIGTRAP
handler.  To avoid this, the software event flag in the augmented SS
must be cleared, ensuring that no single-step trap remains pending when
ERETU completes.

This test checks for that specific scenario—verifying whether the kernel
correctly prevents an infinite SIGTRAP loop in this edge case when FRED
is enabled.

The test should _always_ pass with IDT event delivery, thus no need to
disable the test even when FRED is not enabled.

Signed-off-by: Xin Li (Intel) 
Signed-off-by: Dave Hansen 
Tested-by: Sohil Mehta 
Cc:stable@vger.kernel.org
Link: https://lore.kernel.org/all/20250609084054.2083189-3-xin%40zytor.com

selftests/x86/apx: Add APX test

2025-04-16T07:44:14+00:00

The extended general-purpose registers for APX may contain random data,
which is currently assumed by the xstate testing framework. This allows
the testing of the new userspace feature using the common test code.

Invoke the test entry function from apx.c after enumerating the
state component and adding it to the support list

Signed-off-by: Chang S. Bae 
Signed-off-by: Ingo Molnar 
Reviewed-by: Sohil Mehta 
Cc: Andy Lutomirski 
Cc: H. Peter Anvin 
Cc: Linus Torvalds 
Cc: Oleg Nesterov 
Link: https://lore.kernel.org/r/20250416021720.12305-6-chang.seok.bae@intel.com

selftests/x86/avx: Add AVX tests

2025-02-26T12:05:30+00:00

Add xstate testing specifically for those vector register states,
validating kernel's context switching and ensuring ABI compliance.
Use the established xstate testing framework.

Alternatively, this invocation could be placed directly in
xstate.c::main(). However, the current test file naming convention, which
clearly specifies the tested area, seems reasonable. Adding avx.c
considerably aligns with that convention.

The test output should be like this for ZMM_Hi256 as an example:

  $ avx_64
  ...
  [RUN]   AVX-512 ZMM_Hi256: check context switches, 10 iterations, 5 threads.
  [OK]    No incorrect case was found.
  [RUN]   AVX-512 ZMM_Hi256: inject xstate via ptrace().
  [OK]    'xfeatures' in SW reserved area was correctly written
  [OK]    xstate was correctly updated.
  [RUN]   AVX-512 ZMM_Hi256: load xstate and raise SIGUSR1
  [OK]    'magic1' is valid
  [OK]    'xfeatures' in SW reserved area is valid
  [OK]    'xfeatures' in XSAVE header is valid
  [OK]    xstate delivery was successful
  [OK]    'magic2' is valid
  [RUN]   AVX-512 ZMM_Hi256: load new xstate from sighandler and check it after sigreturn
  [OK]    xstate was restored correctly

But systems without AVX-512 will look like:
  ...
  The kernel does not support feature number: 5
  The kernel does not support feature number: 6
  The kernel does not support feature number: 7

Signed-off-by: Chang S. Bae 
Signed-off-by: Ingo Molnar 
Link: https://lore.kernel.org/r/20250226010731.2456-10-chang.seok.bae@intel.com

selftests/x86/xstate: Refactor context switching test

2025-02-26T12:05:29+00:00

The existing context switching and ptrace tests in amx.c are not specific
to dynamic states, making them reusable for general xstate testing.

As a first step, move the context switching test to xstate.c. Refactor
the test code to allow specifying which xstate component being tested.

To decouple the test from dynamic states, remove the permission request
code. In fact, The permission request inside the test wrapper was
redundant.

Additionally, replace fatal_error() with ksft_exit_fail_msg() for
consistency in error handling.

  Expected output:
  $ amx_64
  ...
  [RUN]   AMX Tile data: check context switches, 10 iterations, 5 threads.
  [OK]    No incorrect case was found.

Signed-off-by: Chang S. Bae 
Signed-off-by: Ingo Molnar 
Link: https://lore.kernel.org/r/20250226010731.2456-5-chang.seok.bae@intel.com

Documentation/srso: Document a method for checking safe RET operates properly

2024-08-27T07:16:35+00:00

Add a method to quickly verify whether safe RET operates properly on
a given system using perf tool.

Also, add a selftest which does the same thing.

Signed-off-by: Borislav Petkov (AMD) 
Link: https://lore.kernel.org/r/20240731160531.28640-1-bp@kernel.org

selftests/x86: avoid -no-pie warnings from clang during compilation

2024-07-11T17:23:55+00:00

When building with clang, via:

    make LLVM=1 -C tools/testing/selftests

...clang warns that -no-pie is "unused during compilation".

This occurs because clang only wants to see -no-pie during linking.
Here, we don't have a separate linking stage, so a compiler warning is
unavoidable without (wastefully) restructuring the Makefile.

Avoid the warning by simply disabling that warning, for clang builds.

Acked-by: Muhammad Usama Anjum 
Signed-off-by: John Hubbard 
Signed-off-by: Shuah Khan

selftests/x86: build sysret_rip.c with clang

2024-07-11T17:23:55+00:00

When building with clang, via:

    make LLVM=1 -C tools/testing/selftests

...the build fails because clang's inline asm doesn't support all of the
features that are used in the asm() snippet in sysret_rip.c.

Fix this by moving the asm code into the clang_helpers_64.S file, where
it can be built with the assembler's full set of features.

Acked-by: Muhammad Usama Anjum 
Signed-off-by: John Hubbard 
Signed-off-by: Shuah Khan

selftests/x86: build fsgsbase_restore.c with clang

2024-07-11T17:23:55+00:00

When building with clang, via:

    make LLVM=1 -C tools/testing/selftests

Fix this by moving the inline asm to "pure" assembly, in two new files:
clang_helpers_32.S, clang_helpers_64.S.

As a bonus, the pure asm avoids the need for ifdefs, and is now very
simple and easy on the eyes.

Acked-by: Muhammad Usama Anjum 
Signed-off-by: John Hubbard 
Signed-off-by: Shuah Khan

selftests/x86: fix Makefile dependencies to work with clang

2024-07-11T17:23:54+00:00

When building with clang, via:

    make LLVM=1 -C tools/testing/selftests

...the following build failure occurs in selftests/x86:

   clang: error: cannot specify -o when generating multiple output files

This happens because, although gcc doesn't complain if you invoke it
like this:

    gcc file1.c header2.h

...clang won't accept that form--it rejects the .h file(s). Also, the
above approach is inaccurate anyway, because file.c includes header2.h
in this case, and the inclusion of header2.h on the invocation is an
artifact of the Makefile's desire to maintain dependencies.

In Makefiles of this type, a better way to do it is to use Makefile
dependencies to trigger the appropriate incremental rebuilds, and
separately use file lists (see EXTRA_FILES in this commit) to track what
to pass to the compiler.

This commit splits those concepts up, by setting up both EXTRA_FILES and
the Makefile dependencies with a single call to the new Makefile
function extra-files.

That fixes the build failure, while still providing the correct
dependencies in all cases.

Acked-by: Muhammad Usama Anjum 
Signed-off-by: John Hubbard 
Signed-off-by: Shuah Khan