Re: [PATCH 09/10] test/py: avb: Add sandbox AVB testing with dedicated mmc12 device

[Mattijs Korpershoek <mkorpershoek@kernel.org>]

Hi Igor,

On Mon, Oct 19, 2026 at 12:26, Igor Opaniuk <igor.opaniuk@oss.qualcomm.com> wrote:

> Hi Mattijs,
>
> On Thu, Oct 15, 2026 at 3:55 PM Mattijs Korpershoek
> <mkorpershoek@kernel.org> wrote:
>>
>> Right now, sandbox runs the AVB tests using mmc1.img, which contains a
>> fedora image.
>> This does not really make sense. We should test on an mmc device which
>> has a proper vbmeta partition instead.
>>
>> Add a new mmc12 in sandbox which contains all required partitions for
>> proper AVB testing.
>> Use the mmc12 device in the avb tests only when running in sandbox.
>> The mmc12 DT node gets enabled by the avb_device_id fixture if CMD_BIND
>> is available.
>>
>> Note: the vbmeta.img has been generated using:
>>
>>     $ ./avbtool.py add_hash_footer \
>>                    --image boot.img \
>>                    --partition_name boot \
>>                    --partition_size 4194304
>>
>>     $ ./avbtool.py make_vbmeta_image \
>>                    --key test/data/testkey_rsa4096.pem \
>>                    --algorithm SHA256_RSA4096 \
>>                    --include_descriptors_from_image boot.img \
>>                    --padding_size 4096 --flags 1 \
>>                    --output vbmeta.img
>>
>>      $ gzip -9 vbmeta.img
>>      $ xxd -p vbmeta.img.gz > vbmeta.img.gz.hex
>>
>> Signed-off-by: Mattijs Korpershoek <mkorpershoek@kernel.org>
>> ---
>>  arch/sandbox/dts/test.dts                   |  8 +++
>>  test/py/tests/test_android/android_image.py | 15 ++++++
>>  test/py/tests/test_android/test_abootimg.py | 77 +++++++++++++++++++++++++++++
>>  test/py/tests/test_android/test_avb.py      | 20 ++++++++
>>  4 files changed, 120 insertions(+)
>>
>> diff --git a/arch/sandbox/dts/test.dts b/arch/sandbox/dts/test.dts
>> index 25c99ef81472..80f505083cd9 100644
>> --- a/arch/sandbox/dts/test.dts
>> +++ b/arch/sandbox/dts/test.dts
>> @@ -50,6 +50,7 @@
>>                 mmc9 = "/mmc9";
>>                 mmc10 = "/mmc10";
>>                 mmc11 = "/mmc11";
>> +               mmc12 = "/mmc12";
>>                 pci0 = &pci0;
>>                 pci1 = &pci1;
>>                 pci2 = &pci2;
>> @@ -1398,6 +1399,13 @@
>>                 filename = "mmc11.img";
>>         };
>>
>> +       /* This is used for Android AVB tests */
>> +       mmc12 {
>> +               status = "disabled";
>> +               compatible = "sandbox,mmc";
>> +               filename = "mmc12.img";
>> +       };
>> +
>>         pch {
>>                 compatible = "sandbox,pch";
>>         };
>> diff --git a/test/py/tests/test_android/android_image.py b/test/py/tests/test_android/android_image.py
>> index abdc6cd28744..72725ac9044c 100644
>> --- a/test/py/tests/test_android/android_image.py
>> +++ b/test/py/tests/test_android/android_image.py
>> @@ -83,7 +83,22 @@ def setup_android_v2_image(ubman):
>>      ]
>>      create_gpt_image(ubman, 8, required_parts, images)
>>
>> +def setup_android_avb_image(ubman):
>> +    """Create mmc12.img: boot image v2 with vbmeta.img."""
>> +
>> +    required_parts = [
>> +        {'num': 1, 'label':'boot', 'size': '4M'},
>> +        {'num': 2, 'label':'system', 'size': '4M'},
>> +        {'num': 3, 'label':'vbmeta', 'size': '4M'},
>> +    ]
>> +    images = [
>> +        (1, 'boot.img', test_abootimg.img_hex),
>> +        (3, 'vbmeta.img', test_abootimg.vbmeta_img_hex),
>> +    ]
>> +    create_gpt_image(ubman, 12, required_parts, images)
>> +
>>  def setup_android_image(ubman):
>>      """Create disk images with Android partitions."""
>>      setup_android_v4_image(ubman)
>>      setup_android_v2_image(ubman)
>> +    setup_android_avb_image(ubman)
>> diff --git a/test/py/tests/test_android/test_abootimg.py b/test/py/tests/test_android/test_abootimg.py
>> index ff54a8318a12..a54e09bb09ba 100644
>> --- a/test/py/tests/test_android/test_abootimg.py
>> +++ b/test/py/tests/test_android/test_abootimg.py
>> @@ -49,6 +49,18 @@ using the same steps above :
>>                  --pagesize 4096  --vendor_ramdisk ./ramdisk.img \
>>                  --header_version 4 --vendor_boot ./vboot.img \
>>
>> +3- vbmeta.img
>> +    $ ./avbtool.py add_hash_footer \
>> +                   --image boot.img \
>> +                   --partition_name boot \
>> +                   --partition_size 4194304
>> +
>> +    $ ./avbtool.py make_vbmeta_image \
>> +                   --key test/data/testkey_rsa4096.pem \
>> +                   --algorithm SHA256_RSA4096 \
>> +                   --include_descriptors_from_image boot.img \
>> +                   --padding_size 4096 --flags 1 \
>> +                   --output vbmeta.img
>>  """
>>
>>  # boot.img.gz hex dump
>> @@ -81,6 +93,71 @@ fae68747835d6dec42bc0df6d74d1fc5a0bfac6e89331797b9564926663a
>>  000080fa912fcae854c55adbeb2769d4ab34c9ad4d16963f010000000000
>>  a88d2fb468951800500000"""
>>
>> +vbmeta_img_hex = """
>> +1f8b0808f36fcf6a020376626d6574612e696d6700edd369301bea1a07f0
>> +7062dfb758521a55b4b650722807572d41ab2d5a6a4b90a225b64aad69c5
>> +d67063b968a9725b91632bb12fb11faa45c4762c8928557b7a6c557b0fee
>> +ccd9e69e993b77eecc9db91feef87df9bfcfbcf3cefbe5f99b385cd10400
>> +006c803fb0ffe5d7e4f86500fc19e4cff9c775efaf01e4fe2d8701ff5aef
>> +3f9d7ff9d323d413131888866869e8686802fef7025c122d02b16f9c05b1
>> +3fd89904c6054cb993631550b20e3d36f0fc97a5fab3e3ab1813c7059894
>> +3024ec1e6a4c412f9d71de37ebb3132b8f25858b29e0a98d19820724a8ad
>> +11ef74e93b156edc57630f18b6788530b0de2f661a5f755bda6b28cc5367
>> +f41f67dc7c008db14b0f961539b149a94adc44317ab0f55f257d50addbb2
>> +6ca967eb2f0240832e33ad34f0165457652a752b30e1a9ea60bb64458785
>> +4d17bf22cc1fc07b777210d3f3e139b0377020d02b59ac2d84ccb5f3ac4a
>> +eeb60e1322f9445a259a6b3c79f2a563e7e16a9c54886ac6323659f8ef85
>> +82e36fd1b7728f1d645495422df053249da0d2c58fe44b24a250cb8f7306
>> +faa26fb8231abdb6ce657cf416e183cb4a111de2a8363c1d8a61b5673f86
>> +01ef83ddc1059b3a370c8a23a5560bd9433d664dde352db09412cab2272f
>> +5a145b363c347439a13b1ecc535e95f53ea79c401b48efa277065eb21467
>> +6f104b19d15d8f4790cce128dd673132db7edc29bb63b0899e25ab1778ce
>> +f14622bd6d9ff0e486336968f432b3c107e9e0fa75044c19e8474936cfec
>> +c85b0a1cad94ac579b390a995d312280a6d3b0dc2224da514ef5965f2749
>> +4733a4324d40ec6bb8b8c7ec2d0bbad1a8ffdbf3743231b1125be6ffe07d
>> +bbf14e2e7c3c7cba09be7b0486e22b708b40cc39d88176eb190bcbb9905c
>> +09cf1c8dbd282817c483f5b7f7b1cc6147f935fb65c5b7d42ad70b5cb49a
>> +667f3d51fd70d38a5dcb017c8df917df58c27485c47fb846bf1781f27b3d
>> +42ee795c827dfb6fdf007feb11e4bfdd61cfc0404cc5d6f032473f5cc44e
>> +f49025bc09950a607ad7114cf1da446413f27b3fc1c875231c6ba6c5d629
>> +179c169fd52add2237fc48f17ee770a9b15ca6ade3094e1c001006dc9e04
>> +9219c0caf9d178f4638124c3aee451d1db2ccfbecf42081ae841991956cd
>> +cbfa693d4815d0c2b921c6657fede06ed3854870fcf34486cff70a07c557
>> +df5b0bede94b55dc2a9138ae2297c3980664e5d6ca9551a8aece84ad2ada
>> +59999ec559e947c1510f35ebaa136a6d5ebf7e03d291a12cf71c1ef08495
>> +6567fe6456310469ddc4894c29f0c3839bfc27a2dce1789043666397ca8b
>> +aa6b6cfc9a8c4cfce65a00a15dd365b7a8721a873547a4a56722cc8e29b1
>> +5ceb11d40ead10cf3bf303ddad5d22b244eb8e63e547c45d1809417def08
>> +35daec737be2bb5fe95dbc36405923229b731364c6792a9e5e3718ea77ed
>> +8bc0edd18aac4b7c19a35a2207bbec281519f511196f30c8a4ad6dcfe607
>> +eb45652b64f49d7965f5c53e6f413b3d90de57d04ff6c64b47ac0284a213
>> +23c2fce49b6b4a0500e7d42e5ba2c441d4b66b4cae141cc650e760918560
>> +1809522a81a6ccc4ba2d1c024739f89af56baccca1f01e0113e36c9c8d71
>> +677d4b10b258b7d2f29ca8b9c68e103e632e9eed4054485ce2fc6052ce7a
>> +53b7645090c4a7f677e8b39eb5dbea20fc570739f3b28a4b0b88f4357b6f
>> +44db1a7949f4b2405cdf8a1f5abd70bddbd9bb22399b2e80b6ead9e9ced0
>> +22f0ac6b334b751baca4f605ddcd7bb5d337208ec2ede1ea714a13548f03
>> +e86c0787a69db3e81940b11b0dabf1f6198164b069aa8198064c09d4eae6
>> +940ee4359aeec1cce4bb6283cb525ed79988accaa5fc2c1e9b713dce97d7
>> +0f867063b9d292672e8f58bb2051a5776779fbf928ced8377c4bedc704a1
>> +473aa9ecde18363435b41cebc30d3596295273af3d61a65044f901d1b49b
>> +44d7bbc439e425afbebcf6095e31fc772ae6707eea95d8c324afe5a4bab4
>> +3db92585c26127dd880cfaa0e1d13c916f089d90eff5c5f59d350a19a0af
>> +af42f06d80b6ecd75cf56c954957f49ebf4f75b7e2dbfd6bbb51a87d5764
>> +0950f2e1e72fdf7882136aaa3670120d63d73f04974fa900c7eae49bbd1c
>> +1c570ee30b1e890956d25fdc5121c5c4a7f0e4fb76b64cee3c296f7be8c1
>> +b3946c1856b3a6095900c866af74f400c0f2d5a065131f8d55bdd645701d
>> +a78256f019ab8150ebd06f53484904ebc86d7caf8490eee55d7f9cf4866b
>> +89f720181421ff81aea5d92d3fade3f2a38caa91dbde272a476a63bf9546
>> +fefc76b1a5b4701eb078fb02a637100551b538af242d3ba2a6e5ef7cb180
>> +b3a8c684c6ab9cc593550ef70abf67fb7c8251a49e3fb43a87d98a9dcf9e
>> +7c3cb6cf17646a581d958d9be8a74bb7a2f88e6c128f7dca29b49b8df76a
>> +5d26e4147f467e9752ad8dadb562330ebe2d68dbeca174f869b17ee5f5d0
>> +40d6ab894ea47d3a996306b26ccb7479e6b3b6bd7ec52b488c2f48fc4cdf
>> +ac3415b9231b7415cd8959add708fb88219272f2135e7e2e673c069c3a75
>> +ead4a953a7feeffd03523602d400100000
>> +"""
>> +
>>  # Expected response for "abootimg dtb_dump" command
>>  dtb_dump_resp="""## DTB area contents (concat format):
>>   - DTB #0:
>> diff --git a/test/py/tests/test_android/test_avb.py b/test/py/tests/test_android/test_avb.py
>> index 34cddc485ebc..75abf5d1b1c7 100644
>> --- a/test/py/tests/test_android/test_avb.py
>> +++ b/test/py/tests/test_android/test_avb.py
>> @@ -13,8 +13,10 @@ For configuration verification:
>>  - Corrupt boot partition and check for failure
>>  - Corrupt vbmeta partition and check for failure
> I know that it existed before, but nothing implements this
> functionality (can be a follow-up series)

Yes, this would require either another mmcX.img with corrupted data or
doing the trick that you did below.

>
> I tried iflipping one byte in the boot payload of mmc12.img makes
> sandbox report:
>
> avb_slot_verify.c:423: ERROR: boot: Hash of data does not match digest
> in descriptor.
> Verification failed, reason: Digest didn't match or signature checks failed

Thanks for testing this.

>
>>  """
>> +import os
>>
>>  import pytest
>> +from android_image import setup_android_avb_image
>>
>>  temp_addr = 0x90000000
>>  temp_addr2 = 0x90002000
>> @@ -22,7 +24,25 @@ temp_addr2 = 0x90002000
>>  @pytest.fixture(scope='function')
>>  def avb_device_id(ubman):
>>      """Returns the device id number for AVB
>> +
>> +    On sandbox, creates mmc12.img and binds the disabled mmc12 DT node.
>> +    On other boards, defaults to device 1.
>>      """
>> +    if ubman.config.buildconfig.get('config_sandbox'):
>> +        if not ubman.config.buildconfig.get('config_cmd_bind'):
>> +            pytest.skip('CMD_BIND required for AVB on sandbox')
>> +
>> +        mmc_dev = 0xc
>> +        fname = os.path.join(ubman.config.source_dir, f'mmc{mmc_dev}.img')
>> +        if not os.path.exists(fname):
>> +            setup_android_avb_image(ubman)
>> +            ubman.restart_uboot()
>
> If setup_android_avb_image() fails part way (e.g. cgpt not installed,
> this was my case :) ),
> qemu-img has already created a 20MiB mmc12.img without partitions. The
> next run then skips the setup and fails with "can't find partition
> 'vbmeta'", which hides the real cause.

I'll add error handling in setup_android_avb_image

>
> Could the image be created under
> a temporary name and renamed on success, or removed on error? Since
> test_avb.py did not need any host tool on sandbox before, a
> pytest.skip() when cgpt is not found (like the CMD_BIND one above) would
> also help people running the suite locally.

Yes, that's a good point.
I will add .skip() in the config_sandbox() conditional to help people
run the suite locally.

>
>> +
>> +        ubman.run_command(f'bind /mmc{mmc_dev} mmc_sandbox')
>> +        # Run mmc list to ensure that mmc_sandbox driver is probed
>> +        ubman.run_command('mmc list')
>> +
>> +        return mmc_dev
>>
>>      # default mmc id
>>      return 1
>>
>> --
>> 2.56.0
>>