diff options
| -rw-r--r-- | mm/gup.c | 14 |
1 files changed, 8 insertions, 6 deletions
@@ -1653,20 +1653,22 @@ long populate_vma_page_range(struct vm_area_struct *vma, if (vma->vm_flags & VM_LOCKONFAULT) return nr_pages; + /* ... similarly, we've never faulted in PROT_NONE pages */ + if (!vma_is_accessible(vma)) + return -EFAULT; + gup_flags = FOLL_TOUCH; /* * We want to touch writable mappings with a write fault in order * to break COW, except for shared mappings because these don't COW * and we would not want to dirty them for nothing. + * + * Otherwise, do a read fault, and use FOLL_FORCE in case it's not + * readable (ie write-only or executable). */ if ((vma->vm_flags & (VM_WRITE | VM_SHARED)) == VM_WRITE) gup_flags |= FOLL_WRITE; - - /* - * We want mlock to succeed for regions that have any permissions - * other than PROT_NONE. - */ - if (vma_is_accessible(vma)) + else gup_flags |= FOLL_FORCE; if (locked) |