X-Git-Url: http://git.cascardo.info/?a=blobdiff_plain;f=mm%2Fmemory.c;h=deb679c31f2ab897cafebf72643aec4f66233308;hb=8605c02205bfcaaf7dcc59c5f9bd3f6acd63e086;hp=9cb27470fee991cb874676bb0cbc0f694b5e1d36;hpb=06a660ada2064bbdcd09aeb8173f2ad128c71978;p=cascardo%2Flinux.git

diff --git a/mm/memory.c b/mm/memory.c
index 9cb27470fee9..deb679c31f2a 100644
--- a/mm/memory.c
+++ b/mm/memory.c
@@ -2426,6 +2426,8 @@ void unmap_mapping_range(struct address_space *mapping,
 	if (details.last_index < details.first_index)
 		details.last_index = ULONG_MAX;
 
+
+	/* DAX uses i_mmap_lock to serialise file truncate vs page fault */
 	i_mmap_lock_write(mapping);
 	if (unlikely(!RB_EMPTY_ROOT(&mapping->i_mmap)))
 		unmap_mapping_range_tree(&mapping->i_mmap, &details);