Re: [PATCH] isa: switch to dynamic root device

[Greg Kroah-Hartman <gregkh@linuxfoundation.org>]

On Mon, May 04, 2026 at 03:35:17PM +0900, William Breathitt Gray wrote:
> On Sun, May 03, 2026 at 05:50:17PM +0200, Danilo Krummrich wrote:
> > On Sun May 3, 2026 at 7:08 AM CEST, William Breathitt Gray wrote:
> > > Would you resend with a Fixes tag
> > 
> > Devices should generally be allocated dynamically for various reasons (e.g. I
> > recently had a case where adding a dynamic lock class key to struct device for
> > debugging purposes caused warnings for all the static devices).
> > 
> > While it clearly should be improved, I don't think this causes a bug in the ISA
> > code -- there is no "real" leak as the device is static anyway and there's no
> > spurious WARN() as release() is never hit, since ISA is always built-in.
> > 
> > I'd assume this is why Johan did not add it in the first place.
> > 
> > That said, if you mean to add a Fixes: tag anyway to indicate the technically
> > wrong usage pattern of struct device, that seems reasonable to me.
> 
> Okay that makes sense, this is improvement of the code rather than a
> true bug fix, so we don't need a Fixes tag.
> 
> Johan, I do have another request. Would you refactor the changes in
> isa_bus_init() to avoid the nested blocks? For example:
> 
> 	error = bus_register(&isa_bus_type);
> 	if (error)
> 		return error;
> 
> 	isa_bus = root_device_register("isa");
> 	if (IS_ERR(isa_bus)) {
> 		bus_unregister(&isa_bus_type);
> 		return PTR_ERR(isa_bus);
> 	}
> 
> 	return 0;
> 
> I believe that makes the logic easier to understand when reading the
> code here.

Nah, for now, it's fine, if you wish to touch this isa code in the
future to "clean it up", that's great, but it should be done in a
separate change.

thanks,

greg k-h