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 <chang.seok.bae@intel.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Reviewed-by: Sohil Mehta <sohil.mehta@intel.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Link: https://lore.kernel.org/r/20250416021720.12305-6-chang.seok.bae@intel.com
Currently, each of the three xstate tests runs as a separate invocation,
requiring the xstate number to be passed and state information to be
reconstructed repeatedly. This approach arose from their individual and
isolated development, but now it makes sense to unify them.
Introduce a wrapper function that first verifies feature availability
from the kernel and constructs the necessary state information once. The
wrapper then sequentially invokes all tests to ensure consistent
execution.
Update the AMX test to use this unified invocation.
Signed-off-by: Chang S. Bae <chang.seok.bae@intel.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Link: https://lore.kernel.org/r/20250226010731.2456-8-chang.seok.bae@intel.com
With the refactored test cases, another xstate exposure to userspace is
through signal delivery. While amx.c includes signal-related scenarios,
its primary focus is on xstate permission management, which is largely
specific to dynamic states.
The remaining gap is testing xstate preservation and restoration across
signal delivery. The kernel defines an ABI for presenting xstate in the
signal frame, closely resembling the hardware XSAVE format, where xstate
modification is also possible.
Introduce a new test case to verify xstate preservation across signal
delivery and return, that is ensuring ABI compatibility by:
- Loading xstate before raising a signal.
- Verifying correct exposure in the signal frame
- Modifying xstate in the signal frame before returning.
- Checking the state restoration upon signal return.
Integrate this test into the AMX test suite as an initial usage site.
Expected output:
$ amx_64
...
[RUN] AMX Tile data: 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] AMX Tile data: load new xstate from sighandler and check it after sigreturn
[OK] xstate was restored correctly
Signed-off-by: Chang S. Bae <chang.seok.bae@intel.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Link: https://lore.kernel.org/r/20250226010731.2456-7-chang.seok.bae@intel.com
Following the refactoring of the context switching test, the ptrace test is
another component reusable for other xstate features. As part of this
restructuring, add a missing check to validate the
user_xstateregs->xstate_fx_sw field in the ABI.
Also, replace err() and fatal_error() with ksft_exit_fail_msg() for
consistency in error handling.
Expected output:
$ amx_64
...
[RUN] AMX Tile data: inject xstate via ptrace().
[OK] 'xfeatures' in SW reserved area was correctly written
[OK] xstate was correctly updated.
Signed-off-by: Chang S. Bae <chang.seok.bae@intel.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Link: https://lore.kernel.org/r/20250226010731.2456-6-chang.seok.bae@intel.com
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 <chang.seok.bae@intel.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Link: https://lore.kernel.org/r/20250226010731.2456-5-chang.seok.bae@intel.com
After moving essential helpers from amx.c, the code remains neutral
regarding which xstate components it handles. However, explicitly listing
known components helps users identify which features are ready for
testing.
Enumerate xstate components to facilitate identification. Extend struct
xstate_info to include a name field, providing a human-readable
identifier.
Signed-off-by: Chang S. Bae <chang.seok.bae@intel.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Link: https://lore.kernel.org/r/20250226010731.2456-4-chang.seok.bae@intel.com
The AMX test introduced several XSAVE-related helper functions, but so
far, it has been the only user of them. These helpers can be generalized
for broader test of multiple xstate features.
Move most XSAVE-related code into xsave.h, making it shareable. The
restructuring includes:
* Establishing low-level XSAVE helpers for saving and restoring register
states, as well as handling XSAVE buffers.
* Generalizing state data manipuldations: set_rand_data()
* Introducing a generic feature query helper: get_xstate_info()
While doing so, remove unused defines in amx.c.
Signed-off-by: Chang S. Bae <chang.seok.bae@intel.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Link: https://lore.kernel.org/r/20250226010731.2456-3-chang.seok.bae@intel.com
