Re: [PATCH v2 07/12] arm64, execmem: extend execmem_params for generated code definitions

Kent Overstreet
2023-06-17T15:37:12Z

On Sat, Jun 17, 2023 at 09:57:59AM +0300, Mike Rapoport wrote:
> > This is growing fast. :) We have 3 now: text, data, jit. And it will be
> > 5 when we split data into rw data, ro data, ro after init data. I wonder
> > whether we should still do some type enum here. But we can revisit
> > this topic later.
>
> I don't think we'd need 5. Four at most :)
>
> I don't know yet what would be the best way to differentiate RW and RO
> data, but ro_after_init surely won't need a new type. It either will be
> allocated as RW and then the caller will have to set it RO after
> initialization is done, or it will be allocated as RO and the caller will
> have to do something like text_poke to update it.

Perhaps ro_after_init could use the same allocation interface and share
pages with ro pages - if we just added a refcount for "this page
currently needs to be rw, module is still loading?"

text_poke() approach wouldn't be workable, you'd have to audit and fix
all module init code in the entire kernel.