diff options
Diffstat (limited to 'arch/x86/boot/compressed/pgtable_64.c')
| -rw-r--r-- | arch/x86/boot/compressed/pgtable_64.c | 16 |
1 files changed, 16 insertions, 0 deletions
diff --git a/arch/x86/boot/compressed/pgtable_64.c b/arch/x86/boot/compressed/pgtable_64.c index 7d0394f4ebf9..5def1674d6f1 100644 --- a/arch/x86/boot/compressed/pgtable_64.c +++ b/arch/x86/boot/compressed/pgtable_64.c @@ -8,6 +8,13 @@ #define BIOS_START_MIN 0x20000U /* 128K, less than this is insane */ #define BIOS_START_MAX 0x9f000U /* 640K, absolute maximum */ +#ifdef CONFIG_X86_5LEVEL +/* __pgtable_l5_enabled needs to be in .data to avoid being cleared along with .bss */ +unsigned int __section(.data) __pgtable_l5_enabled; +unsigned int __section(.data) pgdir_shift = 39; +unsigned int __section(.data) ptrs_per_p4d = 1; +#endif + struct paging_config { unsigned long trampoline_start; unsigned long l5_required; @@ -198,4 +205,13 @@ void cleanup_trampoline(void *pgtable) /* Restore trampoline memory */ memcpy(trampoline_32bit, trampoline_save, TRAMPOLINE_32BIT_SIZE); + + /* Initialize variables for 5-level paging */ +#ifdef CONFIG_X86_5LEVEL + if (__read_cr4() & X86_CR4_LA57) { + __pgtable_l5_enabled = 1; + pgdir_shift = 48; + ptrs_per_p4d = 512; + } +#endif } |