Re: [PATCH V2] driver core: auxiliary bus: Fix sysfs creation on bind

[Danilo Krummrich]

On Fri Feb 20, 2026 at 9:04 AM CET, Leon Romanovsky wrote:
> This init->add->remove->destroy pattern follows standard Linux kernel practice.
> I expect all current review tools to flag any missing function call
> among these three.

I'm not saying that the flow is not logical, goes against existing patterns,
etc., I'm saying that it is unnecessary to expose a new API to drivers, since
this is already handled internally.

I.e. we can easily fix the bug without increasing the API surface exposing a new
API to drivers.

> It is not, atomic is not a replacement for locking and this hunk is
> going to be racy as hell:

No, of course not, but it is sufficient to ensure that something runs only once.

However, you are still right, since sysfs_create_group() can still fail, we
still need the mutex, because we may need to unwind.

> In the proposed patch, locking is handled by the driver, which understands the
> flow far better than the driver core.

I don't think so, the driver core (or actually the auxiliary bus code) is
perfectly aware of the flow, i.e. create the attribute group once actually
needed by auxiliary_device_sysfs_irq_add(), remove it on driver unbind.