diff options
Diffstat (limited to 'arch/x86/mm')
| -rw-r--r-- | arch/x86/mm/pgtable.c | 20 |
1 files changed, 20 insertions, 0 deletions
diff --git a/arch/x86/mm/pgtable.c b/arch/x86/mm/pgtable.c index 217c436acfd3..4bfbe4cb6978 100644 --- a/arch/x86/mm/pgtable.c +++ b/arch/x86/mm/pgtable.c @@ -886,3 +886,23 @@ pmd_t pmd_mkwrite(pmd_t pmd, struct vm_area_struct *vma) return pmd_clear_saveddirty(pmd); } + +void arch_check_zapped_pte(struct vm_area_struct *vma, pte_t pte) +{ + /* + * Hardware before shadow stack can (rarely) set Dirty=1 + * on a Write=0 PTE. So the below condition + * only indicates a software bug when shadow stack is + * supported by the HW. This checking is covered in + * pte_shstk(). + */ + VM_WARN_ON_ONCE(!(vma->vm_flags & VM_SHADOW_STACK) && + pte_shstk(pte)); +} + +void arch_check_zapped_pmd(struct vm_area_struct *vma, pmd_t pmd) +{ + /* See note in arch_check_zapped_pte() */ + VM_WARN_ON_ONCE(!(vma->vm_flags & VM_SHADOW_STACK) && + pmd_shstk(pmd)); +} |