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Diffstat (limited to 'arch/x86/platform/efi/efi_64.c')
-rw-r--r--arch/x86/platform/efi/efi_64.c41
1 files changed, 31 insertions, 10 deletions
diff --git a/arch/x86/platform/efi/efi_64.c b/arch/x86/platform/efi/efi_64.c
index 642a8698ad61..c488625c9712 100644
--- a/arch/x86/platform/efi/efi_64.c
+++ b/arch/x86/platform/efi/efi_64.c
@@ -135,6 +135,7 @@ static pgd_t *efi_pgd;
int __init efi_alloc_page_tables(void)
{
pgd_t *pgd;
+ p4d_t *p4d;
pud_t *pud;
gfp_t gfp_mask;
@@ -147,15 +148,20 @@ int __init efi_alloc_page_tables(void)
return -ENOMEM;
pgd = efi_pgd + pgd_index(EFI_VA_END);
+ p4d = p4d_alloc(&init_mm, pgd, EFI_VA_END);
+ if (!p4d) {
+ free_page((unsigned long)efi_pgd);
+ return -ENOMEM;
+ }
- pud = pud_alloc_one(NULL, 0);
+ pud = pud_alloc(&init_mm, p4d, EFI_VA_END);
if (!pud) {
+ if (CONFIG_PGTABLE_LEVELS > 4)
+ free_page((unsigned long) pgd_page_vaddr(*pgd));
free_page((unsigned long)efi_pgd);
return -ENOMEM;
}
- pgd_populate(NULL, pgd, pud);
-
return 0;
}
@@ -166,6 +172,7 @@ void efi_sync_low_kernel_mappings(void)
{
unsigned num_entries;
pgd_t *pgd_k, *pgd_efi;
+ p4d_t *p4d_k, *p4d_efi;
pud_t *pud_k, *pud_efi;
if (efi_enabled(EFI_OLD_MEMMAP))
@@ -190,23 +197,37 @@ void efi_sync_low_kernel_mappings(void)
memcpy(pgd_efi, pgd_k, sizeof(pgd_t) * num_entries);
/*
+ * As with PGDs, we share all P4D entries apart from the one entry
+ * that covers the EFI runtime mapping space.
+ */
+ BUILD_BUG_ON(p4d_index(EFI_VA_END) != p4d_index(MODULES_END));
+ BUILD_BUG_ON((EFI_VA_START & P4D_MASK) != (EFI_VA_END & P4D_MASK));
+
+ pgd_efi = efi_pgd + pgd_index(EFI_VA_END);
+ pgd_k = pgd_offset_k(EFI_VA_END);
+ p4d_efi = p4d_offset(pgd_efi, 0);
+ p4d_k = p4d_offset(pgd_k, 0);
+
+ num_entries = p4d_index(EFI_VA_END);
+ memcpy(p4d_efi, p4d_k, sizeof(p4d_t) * num_entries);
+
+ /*
* We share all the PUD entries apart from those that map the
* EFI regions. Copy around them.
*/
BUILD_BUG_ON((EFI_VA_START & ~PUD_MASK) != 0);
BUILD_BUG_ON((EFI_VA_END & ~PUD_MASK) != 0);
- pgd_efi = efi_pgd + pgd_index(EFI_VA_END);
- pud_efi = pud_offset(pgd_efi, 0);
-
- pgd_k = pgd_offset_k(EFI_VA_END);
- pud_k = pud_offset(pgd_k, 0);
+ p4d_efi = p4d_offset(pgd_efi, EFI_VA_END);
+ p4d_k = p4d_offset(pgd_k, EFI_VA_END);
+ pud_efi = pud_offset(p4d_efi, 0);
+ pud_k = pud_offset(p4d_k, 0);
num_entries = pud_index(EFI_VA_END);
memcpy(pud_efi, pud_k, sizeof(pud_t) * num_entries);
- pud_efi = pud_offset(pgd_efi, EFI_VA_START);
- pud_k = pud_offset(pgd_k, EFI_VA_START);
+ pud_efi = pud_offset(p4d_efi, EFI_VA_START);
+ pud_k = pud_offset(p4d_k, EFI_VA_START);
num_entries = PTRS_PER_PUD - pud_index(EFI_VA_START);
memcpy(pud_efi, pud_k, sizeof(pud_t) * num_entries);