Re: [PATCH 3/5] powerpc64: Add .opd based function descriptor dereference

Naveen N. Rao
2017-09-16T09:55:45Z

On 2017/09/16 12:53PM, Sergey Senozhatsky wrote:
> We are moving towards separate kernel and module function descriptor
> dereference callbacks. This patch enables it for powerpc64.
>
> For pointers that belong to the kernel
> - Added __start_opd and __end_opd pointers, to track the kernel
> .opd section address range;
>
> - Added dereference_kernel_function_descriptor(). Now we
> will dereference only function pointers that are within
> [__start_opd, __end_opd];
>
> For pointers that belong to a module
> - Added dereference_module_function_descriptor() to handle module
> function descriptor dereference. Now we will dereference only
> pointers that are within [module->opd.start, module->opd.end].

Would it be simpler to just use kernel_text_address() and dereference
everything else? See commit 83e840c770f2c5 ("powerpc64/elfv1: Only
dereference function descriptor for non-text symbols") for a related
patch.

- Naveen