sync mm-stable with mm-hotfixes-stable to pick up depended-upon changes

1 files changed, 9 insertions, 0 deletions

diff --git a/mm/filemap.c b/mm/filemap.c
index c0d7e1d7eea2..67ba56ecdd32 100644
--- a/mm/filemap.c
+++ b/mm/filemap.c
@@ -2608,6 +2608,15 @@ ssize_t filemap_read(struct kiocb *iocb, struct iov_iter *iter,
 		end_offset = min_t(loff_t, isize, iocb->ki_pos + iter->count);
 
 		/*
+		 * Pairs with a barrier in
+		 * block_write_end()->mark_buffer_dirty() or other page
+		 * dirtying routines like iomap_write_end() to ensure
+		 * changes to page contents are visible before we see
+		 * increased inode size.
+		 */
+		smp_rmb();
+
+		/*
 		 * Once we start copying data, we don't want to be touching any
 		 * cachelines that might be contended:
 		 */