Re: [PATCH v8 5/5] selftests/sgx: Refine the test enclave to have storage

[Jarkko Sakkinen <jarkko@kernel.org>]

On Tue, Jun 15, 2021 at 04:14:02PM +0300, Jarkko Sakkinen wrote:
> On Mon, Jun 14, 2021 at 02:16:15PM -0600, Shuah Khan wrote:
> > On 6/10/21 2:30 AM, Jarkko Sakkinen wrote:
> > > Extend the enclave to have two operations: ENCL_OP_PUT and ENCL_OP_GET.
> > > ENCL_OP_PUT stores value inside the enclave address space and
> > > ENCL_OP_GET reads it. The internal buffer can be later extended to be
> > > variable size, and allow reclaimer tests.
> > > 
> > > Signed-off-by: Jarkko Sakkinen <jarkko@kernel.org>
> > > ---
> > >   tools/testing/selftests/sgx/defines.h     | 10 ++++
> > >   tools/testing/selftests/sgx/main.c        | 57 ++++++++++++++++++-----
> > >   tools/testing/selftests/sgx/test_encl.c   | 19 +++++++-
> > >   tools/testing/selftests/sgx/test_encl.lds |  3 +-
> > >   4 files changed, 74 insertions(+), 15 deletions(-)
> > > 
> > 
> > Test output before applying the series:
> > 
> > TAP version 13
> > 1..1
> > # selftests: sgx: test_sgx
> > # Unable to open /dev/sgx_enclave: No such file or directory
> > # 1..0 # SKIP cannot load enclaves
> > ok 1 selftests: sgx: test_sgx # SKIP
> > 
> > Test output after applying second patch
> > 
> > selftests/sgx: Migrate to kselftest harness
> > 
> > Output changes to the following. It doesn't look like the second
> > patch adds any new tests. What is the point in running the tests
> > that fail if /dev/sgx_enclave is missing.
> > 
> > Unfortunately this series doesn't have a cover letter that explains
> > what this series is doing. I don't like the fact that the test
> > output and behavior changes when migrating the test to kselftest
> > harness. Shouldn't the output stay the same as in skip the tests
> > if /dev/sgx_enclave fails.
> 
> I get what you are saying but actually I do not know how with
> fixtures I can skip "the rest" when FIXTURE_SETUP() fails.
> 
> The reason for the output below is that with fixtures for all
> tests enclave is initialized for each test case. And it kind of
> makes sense because all tests start from the clean expected
> state.
> 
> I don't how to do that with zero change in the output.
> 
> The reason to do this change is to make it easy to add more tests,
> and return correct status codes to the framework.

To add: everything I did I based purely to the existing kernel
documentation, following the examples on how to use fixture.

/Jarkko