lazy-pages: start handling remaining pages if IOVs list is not empty

The copied_pages and total_pages may be different because the process may
drop parts of its address space. And the IOVs list will be empty iff we are
done with the process.

travis-ci: success for lazy-pages: add non-#PF events handling (rev2)
Signed-off-by: Mike Rapoport <rppt@linux.vnet.ibm.com>
Signed-off-by: Pavel Emelyanov <xemul@virtuozzo.com>

criu/uffd.c

@@ -659,9 +659,6 @@ static int handle_remaining_pages(struct lazy_pages_info *lpi)
 	struct lazy_iov *iov;
 	int nr_pages, err;
 
-	if (list_empty(&lpi->iovs))
-		return 0;
-
 	iov = list_first_entry(&lpi->iovs, struct lazy_iov, l);
 	nr_pages = iov->len / PAGE_SIZE;
 
@@ -777,7 +774,7 @@ static int handle_requests(int epollfd, struct epoll_event *events, int nr_fds)
 
 		poll_timeout = 0;
 		list_for_each_entry(lpi, &lpis, l) {
-			if (lpi->copied_pages < lpi->total_pages) {
+			if (!list_empty(&lpi->iovs)) {
 				remaining = true;
 				ret = handle_remaining_pages(lpi);
 				if (ret < 0)