block: fix hctx checks for batch allocation

[platform/kernel/linux-starfive.git] / mm / khugepaged.c

diff --git a/mm/khugepaged.c b/mm/khugepaged.c
index 3703a56..c982b25 100644 (file)
--- a/mm/khugepaged.c
+++ b/mm/khugepaged.c
@@ -1467,14 +1467,6 @@ int collapse_pte_mapped_thp(struct mm_struct *mm, unsigned long addr,
        if (!hugepage_vma_check(vma, vma->vm_flags, false, false, false))
                return SCAN_VMA_CHECK;
 
-       /*
-        * Symmetry with retract_page_tables(): Exclude MAP_PRIVATE mappings
-        * that got written to. Without this, we'd have to also lock the
-        * anon_vma if one exists.
-        */
-       if (vma->anon_vma)
-               return SCAN_VMA_CHECK;
-
        /* Keep pmd pgtable for uffd-wp; see comment in retract_page_tables() */
        if (userfaultfd_wp(vma))
                return SCAN_PTE_UFFD_WP;
@@ -1574,8 +1566,14 @@ int collapse_pte_mapped_thp(struct mm_struct *mm, unsigned long addr,
        }
 
        /* step 4: remove pte entries */
+       /* we make no change to anon, but protect concurrent anon page lookup */
+       if (vma->anon_vma)
+               anon_vma_lock_write(vma->anon_vma);
+
        collapse_and_free_pmd(mm, vma, haddr, pmd);
 
+       if (vma->anon_vma)
+               anon_vma_unlock_write(vma->anon_vma);
        i_mmap_unlock_write(vma->vm_file->f_mapping);
 
 maybe_install_pmd:
@@ -2646,7 +2644,7 @@ int madvise_collapse(struct vm_area_struct *vma, struct vm_area_struct **prev,
                                goto out_nolock;
                        }
 
-                       hend = vma->vm_end & HPAGE_PMD_MASK;
+                       hend = min(hend, vma->vm_end & HPAGE_PMD_MASK);
                }
                mmap_assert_locked(mm);
                memset(cc->node_load, 0, sizeof(cc->node_load));