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charset="us-ascii" Content-ID: Content-Transfer-Encoding: quoted-printable Precedence: bulk X-Mailing-List: linux-block@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-MS-Exchange-AntiSpam-ExternalHop-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-ExternalHop-MessageData-0: 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 X-OriginatorOrg: wdc.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-AuthSource: SN7PR04MB8532.namprd04.prod.outlook.com X-MS-Exchange-CrossTenant-Network-Message-Id: 3579e06b-0c36-47a3-80fa-08de599680ef X-MS-Exchange-CrossTenant-originalarrivaltime: 22 Jan 2026 09:13:27.5694 (UTC) X-MS-Exchange-CrossTenant-fromentityheader: Hosted X-MS-Exchange-CrossTenant-id: b61c8803-16f3-4c35-9b17-6f65f441df86 X-MS-Exchange-CrossTenant-mailboxtype: HOSTED X-MS-Exchange-CrossTenant-userprincipalname: LNYRlSxHkjEGQqpRQ9+DGqDJcBj1iZTAZ7lYFIz33u+LLfx+f4W4yns70Z/gPp3s51YsRd+DqODsoj0J5aWbI0bdnjmTziJiAUYYWA1mcH8= X-MS-Exchange-Transport-CrossTenantHeadersStamped: CO6PR04MB7844 On Jan 21, 2026 / 22:35, Christoph Hellwig wrote: > On Wed, Jan 21, 2026 at 01:48:27PM +0100, Daniel Wagner wrote: > > Sure, I'll update the documentation. > >=20 > > On this note, It took me a while to understand that using > > TEST_DEVS=3D"/dev/nvme0n1 /dev/vdb /dev/vdc" is not populating the > > TEST_DEV_ARRAY array. > >=20 > > Commit 653ace845911 ("check, new: introduce test_device_array()") > > explains why: > >=20 > > As to the test target devices defined in TEST_DEVS variable, blktes= ts > > assumes that each test case with test_device() function is run for = each > > single device defined in TEST_DEVS. On the other hand, it is sugges= ted > > to support a test case for not a single device but multiple devices= . > >=20 > > Maybe we could add a default config with all options listed and > > documented but commented out. >=20 > The default config would be useful for sure. Agreed. It can be the file named "config.example". > But I also thing the TEST_DEVS vs TEST_DEV_ARRAY thing is weird, and the > fact that you need to declare the array for multiple tests doesn't help. >=20 > IMHO having a TEST_DEV_ARRAY should imply that normal single device tests > pick the first one from it if not explicit TEST_DEVS is set, and tests > using multiple devices can grab as many as they support from it. That > would mirror what SCRATCH_DEV_POOL does in xfstests, which works very > well. >=20 > I'd love to help with this, but I'm not sure my bash abilities are > enough for this :( When I introduced TEST_DEV_ARRAY, the motivation was the test case md/003. = It was the first test case that required multiple devices for testing. It test= s "NMVe Atomic Writes with MD devices". My assumption was that users wants to specify test target devices unique to md/003 which are different devices fr= om other test cases (special NVMe with atomic write capability). Based on this understanding, I introduced the associative array config option TEST_CASE_DEV_ARRAY[X/0??]=3D"/dev/Y /dev/Z", which can specify test target devices unique to each test case (or multiple test cases specified with reg= ular expression). I think this TEST_CASE_DEV_ARRAY fits the use case of md/003. On the other hand, reading the comment above, I find there is another diffe= rent expectation for testing with multiple devices. As to bcache/* test cases, t= he test target devices can be common to other test groups. I can understand th= at something similar as SCRATCH_DEV_POOL of fstests is desired to reduce the n= umber of config options to specify. We maybe able to introduce the new config opt= ion "TEST_DEV_POOL", which will work as described above: for most of the test cases with test_device() function, blktests can pick up only the first devi= ce from TEST_DEV_POOL. If the test case has test_device_array(), all devices i= n TEST_DEV_POOL can be provided to test_device_array() through TEST_DEV_ARRAY= . The user can specify only TEST_DEV_POOL, to cover both test cases with test_device() and those with test_device_array(). I will try to find my time to prototype TEST_DEV_POOL to see if the expecta= tion can be fulfilled.=