On Thu, Jul 09, 2020 at 11:49:21PM +0300, Mike Rapoport wrote: > > +#ifndef CONFIG_GENERIC_DEVMEM_IS_ALLOWED > > +extern int devmem_is_allowed(unsigned long pfn); > > +#endif Nit: no need for the extern here. > > +config GENERIC_LIB_DEVMEM_IS_ALLOWED > > + bool > > + select ARCH_HAS_DEVMEM_IS_ALLOWED > > This seems to work the other way around from the usual Kconfig chains. > In the most cases ARCH_HAS_SOMETHING selects GENERIC_SOMETHING. > > I believe nicer way would be to make > > config STRICT_DEVMEM > bool "Filter access to /dev/mem" > depends on MMU && DEVMEM > depends on ARCH_HAS_DEVMEM_IS_ALLOWED || GENERIC_LIB_DEVMEM_IS_ALLOWED > > config GENERIC_LIB_DEVMEM_IS_ALLOWED > bool > > and then s/select ARCH_HAS_DEVMEM_IS_ALLOWED/select GENERIC_LIB_DEVMEM_IS_ALLOWED/ > in the arch Kconfigs and drop ARCH_HAS_DEVMEM_IS_ALLOWED in the end. To take a step back: Is there any reason to not just always STRICT_DEVMEM? Maybe for a few architectures that don't currently support a strict /dev/mem the generic version isn't quite correct, but someone selecting the option and finding the issue is the best way to figure that out..
