[PATCH v2 06/17] mm: doc comment for scary spot in write_one_page

From: Jeff Layton
Date: Wed Apr 12 2017 - 08:06:40 EST


Not sure what to do here just yet.

Signed-off-by: Jeff Layton <jlayton@xxxxxxxxxx>
---
mm/page-writeback.c | 6 ++++++
1 file changed, 6 insertions(+)

diff --git a/mm/page-writeback.c b/mm/page-writeback.c
index de0dbf12e2c1..3ac8399dc984 100644
--- a/mm/page-writeback.c
+++ b/mm/page-writeback.c
@@ -2388,6 +2388,12 @@ int write_one_page(struct page *page)
ret = mapping->a_ops->writepage(page, &wbc);
if (ret == 0) {
wait_on_page_writeback(page);
+ /*
+ * FIXME: is this racy? What guarantees that PG_error
+ * will still be set once we get around to checking it?
+ * What if writeback fails, but then a read is issued
+ * before we check this, and that calls ClearPageError?
+ */
if (PageError(page))
ret = -EIO;
}
--
2.9.3