Subject: don't allow transparent hugepage support without PSE From: Andrea Arcangeli Archs implementing Transparent Hugepage Support must implement a function called has_transparent_hugepage to be sure the virtual or physical CPU supports Transparent Hugepages. Signed-off-by: Andrea Arcangeli --- diff --git a/arch/x86/include/asm/pgtable.h b/arch/x86/include/asm/pgtable.h --- a/arch/x86/include/asm/pgtable.h +++ b/arch/x86/include/asm/pgtable.h @@ -158,6 +158,11 @@ static inline int pmd_trans_huge(pmd_t p { return pmd_val(pmd) & _PAGE_PSE; } + +static inline int has_transparent_hugepage(void) +{ + return cpu_has_pse; +} #endif /* CONFIG_TRANSPARENT_HUGEPAGE */ static inline pte_t pte_set_flags(pte_t pte, pteval_t set) diff --git a/mm/huge_memory.c b/mm/huge_memory.c --- a/mm/huge_memory.c +++ b/mm/huge_memory.c @@ -487,7 +487,15 @@ static int __init hugepage_init(void) int err; #ifdef CONFIG_SYSFS static struct kobject *hugepage_kobj; +#endif + err = -EINVAL; + if (!has_transparent_hugepage()) { + transparent_hugepage_flags = 0; + goto out; + } + +#ifdef CONFIG_SYSFS err = -ENOMEM; hugepage_kobj = kobject_create_and_add("transparent_hugepage", mm_kobj); if (unlikely(!hugepage_kobj)) {