arm64/efi/libstub: Make screen_info accessible to the UEFI stub

Unlike on 32-bit ARM, where we need to pass the stub's version of struct
screen_info to the kernel proper via a configuration table, on 64-bit ARM
it simply involves making the core kernel's copy of struct screen_info
visible to the stub by exposing an __efistub_ alias for it.

Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Matt Fleming <matt@codeblueprint.co.uk>
Acked-by: Will Deacon <will.deacon@arm.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: David Herrmann <dh.herrmann@gmail.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Peter Jones <pjones@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-efi@vger.kernel.org
Link: http://lkml.kernel.org/r/1461614832-17633-21-git-send-email-matt@codeblueprint.co.uk
Signed-off-by: Ingo Molnar <mingo@kernel.org>
This commit is contained in:
Ard Biesheuvel 2016-04-25 21:06:52 +01:00 committed by Ingo Molnar
parent 07ea7ec5df
commit 57fdb89aeb
3 changed files with 7 additions and 0 deletions

View File

@ -56,6 +56,9 @@ int efi_create_mapping(struct mm_struct *mm, efi_memory_desc_t *md);
#define __efi_call_early(f, ...) f(__VA_ARGS__)
#define efi_is_64bit() (true)
#define alloc_screen_info(x...) &screen_info
#define free_screen_info(x...)
#define EFI_ALLOC_ALIGN SZ_64K
/*

View File

@ -56,6 +56,9 @@ static __init pteval_t create_mapping_protection(efi_memory_desc_t *md)
return pgprot_val(PAGE_KERNEL_EXEC);
}
/* we will fill this structure from the stub, so don't put it in .bss */
struct screen_info screen_info __section(.data);
int __init efi_create_mapping(struct mm_struct *mm, efi_memory_desc_t *md)
{
pteval_t prot_val = create_mapping_protection(md);

View File

@ -112,6 +112,7 @@ __efistub___memset = KALLSYMS_HIDE(__pi_memset);
__efistub__text = KALLSYMS_HIDE(_text);
__efistub__end = KALLSYMS_HIDE(_end);
__efistub__edata = KALLSYMS_HIDE(_edata);
__efistub_screen_info = KALLSYMS_HIDE(screen_info);
#endif