Re: [PATCH v4 4/4] iommu/io-pgtable-arm-selftests: Use KUnit

[Pranjal Shrivastava <praan@google.com>]

On Mon, Sep 22, 2025 at 08:59:28AM +0000, Mostafa Saleh wrote:
> Integrate the selftests as part of kunit.
> 
> Now instead of the test only being run at boot, it can run:
> 
> - With CONFIG_IOMMU_IO_PGTABLE_LPAE_KUNIT_TEST=y
>   It will automatically run at boot as before.
> 
> - Otherwise with CONFIG_IOMMU_IO_PGTABLE_KUNIT_TEST=m:
>   1) on module load:
>      Once the module load the self test will run
>      # modprobe io-pgtable-arm-selftests
> 
>   2) debugfs
>      With CONFIG_KUNIT_DEBUGFS=y You can run the test with
>      # echo 1 > /sys/kernel/debug/kunit/io-pgtable-arm-test/run
> 
>   3) Using kunit.py
>      You can also use the helper script which uses Qemu in the background
> 
>      # ./tools/testing/kunit/kunit.py run --build_dir build_kunit_arm64 --arch arm64 \
>        --make_options LLVM=1 --kunitconfig ./kunit/kunitconfig
>       [18:01:09] ============= io-pgtable-arm-test (1 subtest) ==============
>       [18:01:09] [PASSED] arm_lpae_do_selftests
>       [18:01:09] =============== [PASSED] io-pgtable-arm-test ===============
>       [18:01:09] ============================================================
> 
> Suggested-by: Jason Gunthorpe <jgg@ziepe.ca>
> Reviewed-by: Jason Gunthorpe <jgg@nvidia.com>
> Signed-off-by: Mostafa Saleh <smostafa@google.com>
> ---
>  drivers/iommu/Kconfig                    | 11 ++--
>  drivers/iommu/Makefile                   |  2 +-
>  drivers/iommu/io-pgtable-arm-selftests.c | 82 +++++++++++++-----------
>  3 files changed, 51 insertions(+), 44 deletions(-)
> 

Reviewed-by: Pranjal Shrivastava <praan@google.com>

Moving the io-pgtable selftests out of the main driver code and
the integration with the KUnit framework looks good to me.

I was able to apply, build and test the series with multiple configs on
QEMU virt. 

   # arm_lpae_do_selftests: selftest: pgsize_bitmap 0x20010000, IAS 40 OAS 44
   # arm_lpae_do_selftests: selftest: pgsize_bitmap 0x20010000, IAS 42 OAS 44
   # arm_lpae_do_selftests: selftest: pgsize_bitmap 0x20010000, IAS 44 OAS 44
   # arm_lpae_do_selftests: selftest: pgsize_bitmap 0x20010000, IAS 32 OAS 48
   # arm_lpae_do_selftests: selftest: pgsize_bitmap 0x20010000, IAS 36 OAS 48
   # arm_lpae_do_selftests: selftest: pgsize_bitmap 0x20010000, IAS 40 OAS 48
   # arm_lpae_do_selftests: selftest: pgsize_bitmap 0x20010000, IAS 42 OAS 48
   # arm_lpae_do_selftests: selftest: pgsize_bitmap 0x20010000, IAS 44 OAS 48
   # arm_lpae_do_selftests: selftest: pgsize_bitmap 0x20010000, IAS 48 OAS 48
   # arm_lpae_do_selftests: selftest: completed with 63 PASS 0 FAIL
   ok 1 arm_lpae_do_selftests
 ok 1 io-pgtable-arm-test

Thanks,
Praan