diff options
| -rw-r--r-- | fs/proc/task_mmu.c | 24 |
1 files changed, 20 insertions, 4 deletions
diff --git a/fs/proc/task_mmu.c b/fs/proc/task_mmu.c index ef2eb12906da..a6f88cbfb689 100644 --- a/fs/proc/task_mmu.c +++ b/fs/proc/task_mmu.c @@ -1982,15 +1982,31 @@ static int pagemap_scan_test_walk(unsigned long start, unsigned long end, struct pagemap_scan_private *p = walk->private; struct vm_area_struct *vma = walk->vma; unsigned long vma_category = 0; + bool wp_allowed = userfaultfd_wp_async(vma) && + userfaultfd_wp_use_markers(vma); - if (userfaultfd_wp_async(vma) && userfaultfd_wp_use_markers(vma)) - vma_category |= PAGE_IS_WPALLOWED; - else if (p->arg.flags & PM_SCAN_CHECK_WPASYNC) - return -EPERM; + if (!wp_allowed) { + /* User requested explicit failure over wp-async capability */ + if (p->arg.flags & PM_SCAN_CHECK_WPASYNC) + return -EPERM; + /* + * User requires wr-protect, and allows silently skipping + * unsupported vmas. + */ + if (p->arg.flags & PM_SCAN_WP_MATCHING) + return 1; + /* + * Then the request doesn't involve wr-protects at all, + * fall through to the rest checks, and allow vma walk. + */ + } if (vma->vm_flags & VM_PFNMAP) return 1; + if (wp_allowed) + vma_category |= PAGE_IS_WPALLOWED; + if (!pagemap_scan_is_interesting_vma(vma_category, p)) return 1; |