Re: [PATCHv10 04/11] efi/x86: Implement support for unaccepted memory

[Kirill A. Shutemov]

On Tue, May 09, 2023 at 12:11:41AM +0200, Ard Biesheuvel wrote:
> > @@ -1324,13 +1325,15 @@ void __init e820__memblock_setup(void)
> >          * e820_table is not finalized and e820__end_of_ram_pfn() cannot be
> >          * used to get correct RAM size.
> >          */
> > -       if (boot_params.unaccepted_memory) {
> > +       if (efi.unaccepted != EFI_INVALID_TABLE_ADDR) {
> > +               struct efi_unaccepted_memory *unaccepted;
> >                 unsigned long size;
> >
> > -               /* One bit per 2MB */
> > -               size = DIV_ROUND_UP(e820__end_of_ram_pfn() * PAGE_SIZE,
> > -                                   PMD_SIZE * BITS_PER_BYTE);
> > -               memblock_reserve(boot_params.unaccepted_memory, size);
> > +               unaccepted = __va(efi.unaccepted);
> > +
> > +               size = sizeof(struct efi_unaccepted_memory);
> > +               size += unaccepted->size;
> > +               memblock_reserve(efi.unaccepted, size);
> >         }
> >
> 
> This could be moved to generic code (but we'll need to use early_memremap())

I don't understand why early_memremap() is needed. EFI_LOADER_DATA already
mapped into direct mapping. We only need to reserve the memory so it
could not be reallocated for other things. Hm?

-- 
  Kiryl Shutsemau / Kirill A. Shutemov