cifs_write_back_from_locked_folio() should return the number of bytes read, but returns the result of ->async_writev(), which will be 0 on success. As it happens, this doesn't prevent cifs_writepages_region() from working as it will then examine and ignore the pages that are no longer dirty rather than just skipping over them. Fixes: d08089f649a0 ("cifs: Change the I/O paths to use an iterator rather than a page list") Signed-off-by: David Howells <dhowells@xxxxxxxxxx> cc: Steve French <sfrench@xxxxxxxxx> cc: Shyam Prasad N <nspmangalore@xxxxxxxxx> cc: Rohith Surabattula <rohiths.msft@xxxxxxxxx> cc: Tom Talpey <tom@xxxxxxxxxx> cc: Jeff Layton <jlayton@xxxxxxxxxx> cc: linux-cifs@xxxxxxxxxxxxxxx --- fs/cifs/file.c | 1 + 1 file changed, 1 insertion(+) diff --git a/fs/cifs/file.c b/fs/cifs/file.c index ebfcaae8c437..f8cc68ce9d8a 100644 --- a/fs/cifs/file.c +++ b/fs/cifs/file.c @@ -2839,6 +2839,7 @@ static ssize_t cifs_write_back_from_locked_folio(struct address_space *mapping, free_xid(xid); if (rc == 0) { wbc->nr_to_write = count; + rc = len; } else if (is_retryable_error(rc)) { cifs_pages_write_redirty(inode, start, len); } else {