find_get_pages_range() and find_get_pages_range_tag() already correctly increment reference count on head when seeing compound page, but they may still use page index from tail. Page index from tail is always zero, so these functions don't work on huge shmem. This hasn't been a problem because, AFAIK, nobody calls these functions on (huge) shmem. Fix them anyway just in case. Signed-off-by: Yu Zhao <yuzhao@xxxxxxxxxx> --- mm/filemap.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/mm/filemap.c b/mm/filemap.c index 81adec8ee02c..cf5fd773314a 100644 --- a/mm/filemap.c +++ b/mm/filemap.c @@ -1704,7 +1704,7 @@ unsigned find_get_pages_range(struct address_space *mapping, pgoff_t *start, pages[ret] = page; if (++ret == nr_pages) { - *start = page->index + 1; + *start = xas.xa_index + 1; goto out; } continue; @@ -1850,7 +1850,7 @@ unsigned find_get_pages_range_tag(struct address_space *mapping, pgoff_t *index, pages[ret] = page; if (++ret == nr_pages) { - *index = page->index + 1; + *index = xas.xa_index + 1; goto out; } continue; -- 2.20.1.97.g81188d93c3-goog