Re: [PATCH v7 17/22] selftests/liveupdate: Add kexec-based selftest for

[Mike Rapoport]

On Sat, Nov 22, 2025 at 05:23:44PM -0500, Pasha Tatashin wrote:
> Subject: selftests/liveupdate: Add kexec-based selftest for

                                                         ^ for what? ;-)

> Introduce a kexec-based selftest, luo_kexec_simple, to validate the
> end-to-end lifecycle of a Live Update Orchestrator (LUO) session across
> a reboot.
> 
> While existing tests verify the uAPI in a pre-reboot context, this test
> ensures that the core functionality—preserving state via Kexec Handover
> and restoring it in a new kernel—works as expected.
> 
> The test operates in two stages, managing its state across the reboot by
> preserving a dedicated "state session" containing a memfd. This
> mechanism dogfoods the LUO feature itself for state tracking, making the
> test self-contained.
> 
> The test validates the following sequence:
> 
> Stage 1 (Pre-kexec):
>  - Creates a test session (test-session).
>  - Creates and preserves a memfd with a known data pattern into the test
>    session.
>  - Creates the state-tracking session to signal progression to Stage 2.
>  - Executes a kexec reboot via a helper script.
> 
> Stage 2 (Post-kexec):
>  - Retrieves the state-tracking session to confirm it is in the
>    post-reboot stage.
>  - Retrieves the preserved test session.
>  - Restores the memfd from the test session and verifies its contents
>    match the original data pattern written in Stage 1.
>  - Finalizes both the test and state sessions to ensure a clean
>    teardown.
> 
> The test relies on a helper script (do_kexec.sh) to perform the reboot
> and a shared utility library (luo_test_utils.c) for common LUO
> operations, keeping the main test logic clean and focused.
> 
> Signed-off-by: Pasha Tatashin <pasha.tatashin@xxxxxxxxxx>
> Reviewed-by: Zhu Yanjun <yanjun.zhu@xxxxxxxxx>

Reviewed-by: Mike Rapoport (Microsoft) <rppt@xxxxxxxxxx>

> ---
>  tools/testing/selftests/liveupdate/Makefile   |   6 +
>  .../testing/selftests/liveupdate/do_kexec.sh  |  16 ++
>  .../selftests/liveupdate/luo_kexec_simple.c   |  89 ++++++
>  .../selftests/liveupdate/luo_test_utils.c     | 266 ++++++++++++++++++
>  .../selftests/liveupdate/luo_test_utils.h     |  44 +++
>  5 files changed, 421 insertions(+)
>  create mode 100755 tools/testing/selftests/liveupdate/do_kexec.sh
>  create mode 100644 tools/testing/selftests/liveupdate/luo_kexec_simple.c
>  create mode 100644 tools/testing/selftests/liveupdate/luo_test_utils.c
>  create mode 100644 tools/testing/selftests/liveupdate/luo_test_utils.h

-- 
Sincerely yours,
Mike.