On Sat, Aug 14, 2010 at 3:18 AM, Takao Indoh <indou.takao at jp.fujitsu.com> wrote:
> diff -Nurp linux-2.6.35.org/arch/x86/kernel/efi_64.c linux-2.6.35/arch/x86/kernel/efi_64.c
> --- linux-2.6.35.org/arch/x86/kernel/efi_64.c ? 2010-08-01 18:11:14.000000000 -0400
> +++ linux-2.6.35/arch/x86/kernel/efi_64.c ? ? ? 2010-08-13 14:39:25.819105004 -0400
> @@ -39,7 +39,9 @@
> ?#include <asm/fixmap.h>
>
> ?static pgd_t save_pgd __initdata;
> -static unsigned long efi_flags __initdata;
> +static unsigned long efi_flags;
> +static pgd_t efi_pgd[PTRS_PER_PGD] __page_aligned_bss;
> +static unsigned long save_cr3;
>
> ?static void __init early_mapping_set_exec(unsigned long start,
> ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ?unsigned long end,
> @@ -98,6 +100,19 @@ void __init efi_call_phys_epilog(void)
> ? ? ? ?early_runtime_code_mapping_set_exec(0);
> ?}
>
> +void efi_call_phys_prelog_in_physmode(void)
> +{
> + ? ? ? local_irq_save(efi_flags);
> + ? ? ? save_cr3 = read_cr3();
> + ? ? ? write_cr3(virt_to_phys(efi_pgd));
> +}
> +
> +void efi_call_phys_epilog_in_physmode(void)
> +{
> + ? ? ? write_cr3(save_cr3);
> + ? ? ? local_irq_restore(efi_flags);
> +}
efi_flags and save_cr3 should be per-CPU, because they now will be
used after SMP is enabled.
efi_pgd should be dynamically allocated instead of statically
allocated, because EFI may be not enabled on some platform.
And I think it is better to unify early physical mode with run-time
physical mode. Just allocate the page table with early page allocator
(lmb?).
Best Regards,
Huang Ying
