Hi David,
On Wed, Jul 19, 2023 at 05:13:45PM +0800, David Gow wrote:
On Wed, 28 Jun 2023 at 17:49, Maxime Ripard mripard@kernel.org wrote:
The root devices show some odd behaviours compared to regular "bus" devices that have been probed through the usual mechanism, so let's create kunit tests to exercise those paths and odd cases.
Signed-off-by: Maxime Ripard maxime@cerno.tech
Reviewed-by: David Gow davidgow@google.com
Thanks!
There's definitely an argument that root devices are not supposed to be like regular devices, and so devm_ managed resources aren't supposed to work with them. Either way:
- It needs to be documented somewhere (and this test makes for good
documentation, IMO).
- It should be consistent: if devm_ isn't to be used with root
devices, it should fail everywhere, and if it is, it should work in all the cases below.
So I'm all in favour of including this test and making root devices work.
I agree 100%. I've reworded the commit log a bit to make it clearer that's what we should strive for, and that this is what this patch is doing.
That being said, I am planning to send out a patchset adding a struct kunit_device for use in tests, which will be attached to a "kunit" bus. I think the combination of "fix devm_ with root devices" and "don't recommend root devices as a 'fake' device for testing" is probably the longer-term solution everyone can agree upon?
Yeah, that sounds reasonable to me
Maxime