diff --git a/mm/readahead.c b/mm/readahead.c
index 3a4b5d58eeb6..95718f87bd43 100644
--- a/mm/readahead.c
+++ b/mm/readahead.c
@@ -467,7 +467,7 @@ 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;
@@ -483,15 +483,22 @@ void page_cache_ra_order(struct readahead_control *ractl,
 
 	limit = min(limit, index + ra->size - 1);
 
+	/* See comment in page_cache_ra_unbounded() */
+	nofs = memalloc_nofs_save();
+	filemap_invalidate_lock_shared(mapping);
+
+	/*
+	 * Re-read min_order after acquiring the invalidate_lock to avoid a
+	 * race with set_blocksize() which can change the mapping's min_order
+	 * while holding the invalidate_lock exclusively.
+	 */
+	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);
 
 	ra->order = new_order;
 
-	/* 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