fix mm-add-and-use-find_lock_entries.patch

Link: https://lkml.kernel.org/r/20201124041507.28996-3-willy@infradead.org
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

diff --git a/mm/filemap.c b/mm/filemap.c
index 9a1ac0b1610543bce662d960f869f699505950a4..682a0d3f0a78731917ee9cddaa707df1223afd39 100644 (file)
--- a/mm/filemap.c
+++ b/mm/filemap.c
@@ -1972,6 +1972,8 @@ unsigned find_lock_entries(struct address_space *mapping, pgoff_t start,
                                goto put;
                        if (page->mapping != mapping || PageWriteback(page))
                                goto unlock;
+                       VM_BUG_ON_PAGE(!thp_contains(page, xas.xa_index),
+                                       page);
                }
                indices[pvec->nr] = xas.xa_index;
                if (!pagevec_add(pvec, page))