diff options
| -rw-r--r-- | arch/x86/mm/pgtable.c | 9 |
1 files changed, 5 insertions, 4 deletions
diff --git a/arch/x86/mm/pgtable.c b/arch/x86/mm/pgtable.c index 027e1d32925c..ca07db510d26 100644 --- a/arch/x86/mm/pgtable.c +++ b/arch/x86/mm/pgtable.c @@ -121,16 +121,17 @@ static void pgd_dtor(pgd_t *pgd) * processor notices the update. Since this is expensive, and * all 4 top-level entries are used almost immediately in a * new process's life, we just pre-populate them here. - * - * Also, if we're in a paravirt environment where the kernel pmd is - * not shared between pagetables (!SHARED_KERNEL_PMDS), we allocate - * and initialize the kernel pmds here. */ #define PREALLOCATED_PMDS (static_cpu_has(X86_FEATURE_PTI) ? \ PTRS_PER_PGD : KERNEL_PGD_BOUNDARY) #define MAX_PREALLOCATED_PMDS PTRS_PER_PGD /* + * "USER_PMDS" are the PMDs for the user copy of the page tables when + * PTI is enabled. They do not exist when PTI is disabled. Note that + * this is distinct from the user _portion_ of the kernel page tables + * which always exists. + * * We allocate separate PMDs for the kernel part of the user page-table * when PTI is enabled. We need them to map the per-process LDT into the * user-space page-table. |