ocfs2: Fix deadlock when allocating page
We cannot call grab_cache_page() when holding filesystem locks or with
a transaction started as grab_cache_page() calls page allocation with
GFP_KERNEL flag and thus page reclaim can recurse back into the filesystem
causing deadlocks or various assertion failures. We have to use
find_or_create_page() instead and pass it GFP_NOFS as we do with other
allocations.
Acked-by: Mark Fasheh <mfasheh@suse.com>
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Tao Ma <tao.ma@oracle.com>
diff --git a/fs/ocfs2/alloc.c b/fs/ocfs2/alloc.c
index 215e12c..592fae5 100644
--- a/fs/ocfs2/alloc.c
+++ b/fs/ocfs2/alloc.c
@@ -6672,7 +6672,7 @@
last_page_bytes = PAGE_ALIGN(end);
index = start >> PAGE_CACHE_SHIFT;
do {
- pages[numpages] = grab_cache_page(mapping, index);
+ pages[numpages] = find_or_create_page(mapping, index, GFP_NOFS);
if (!pages[numpages]) {
ret = -ENOMEM;
mlog_errno(ret);