Re: [PATCH 0/5] [RFC] printk/ia64/ppc64/parisc64: let's deprecate %pF/%pf printk specifiers

[Helge Deller <deller@gmx.de>]

On 20.09.2017 10:41, David Laight wrote:
> From: Helge Deller
>> Sent: 19 September 2017 21:08
> ...
>>> Using 'unsigned long' for any kind of pointer is an accident
>>> waiting do happen.
>>> It also makes it difficult to typecheck the function calls.
>>> Using 'void *' isn't any better.
>>> Either a pointer to an undefined struct, or a struct containing
>>> a single 'char' member, is likely to be safest.
>>
>> David, you might be right in most cases, but in this case I'd prefer
>> unsigned long too. I think this will create the least amount of
>> typecasts here.
> 
> I've not looked at the specifics case...
> 
> Another option is using a struct with a single member and
> passing it by value.

Actually, we do already have correct structs which could be referenced:
parisc: struct Elf64_Fdesc
ia64:	struct fdesc
ppc64:	struct ppc64_opd_entry

One could "#define platform_opd_entry" to each of those depending on the platform and use it.
It might be misleading though, because the pointer which is handed over to
dereference_function_descriptor() can be such a pointer but isn't necessary.
I'll leave it up to Sergey to decide.

Helge