The established xstate test code is designed to be generic, but certain
xstates require special handling and cannot be tested without additional
adjustments.
Clarify which xstates are currently supported, and enforce testing only
for them.
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/20250226010731.2456-9-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
Colin Ian King
Chang S. Bae