diff --git a/mm/readahead.c b/mm/readahead.c
index 406756d34309..d68b75e0848b 100644
--- a/mm/readahead.c
+++ b/mm/readahead.c
@@ -462,7 +462,7 @@ void page_cache_ra_order(struct readahead_control *ractl,
 	struct address_space *mapping = ractl->mapping;
 	pgoff_t start = readahead_index(ractl);
 	pgoff_t index = start;
-	unsigned int min_order = mapping_min_folio_order(mapping);
+	unsigned int min_order;
 	pgoff_t limit = (i_size_read(mapping->host) - 1) >> PAGE_SHIFT;
 	pgoff_t mark = index + ra->size - ra->async_size;
 	unsigned int nofs;
@@ -477,6 +477,10 @@ void page_cache_ra_order(struct readahead_control *ractl,
 
 	limit = min(limit, index + ra->size - 1);
 
+	filemap_invalidate_lock_shared(mapping);
+
+	min_order = mapping_min_folio_order(mapping);
+
 	new_order = min(mapping_max_folio_order(mapping), new_order);
 	new_order = min_t(unsigned int, new_order, ilog2(ra->size));
 	new_order = max(new_order, min_order);
@@ -485,7 +489,6 @@ void page_cache_ra_order(struct readahead_control *ractl,
 
 	/* See comment in page_cache_ra_unbounded() */
 	nofs = memalloc_nofs_save();
-	filemap_invalidate_lock_shared(mapping);
 	/*
 	 * If the new_order is greater than min_order and index is
 	 * already aligned to new_order, then this will be noop as index