On Fri, Apr 30, 2021 at 04:49:35PM +0800, Art Nikpal wrote:

> Yep! but

Please don't top post, reply in line with needed context.  This allows
readers to readily follow the flow of conversation and understand what
you are talking about and also helps ensure that everything in the
discussion is being addressed.

> if i try call spi_master_put(master) or spi_unregister_controller(master);
> it's made Segmentation fault for me
> 
> what's wrong - may be somebody can help me

Probably something is referencing the controller afer it was freed, I do
notice that the current version of the driver uses devm_ to register the
controller so you'd end up with a double free unless you either use devm_
when freeing or change to a normal registration.