From ba95a6225b02c24d99f39fd930b6a388e5fd7b48 Mon Sep 17 00:00:00 2001 From: Stefano Garzarella Date: Thu, 14 Oct 2021 17:20:45 +0200 Subject: [PATCH] vsock_diag_test: remove free_sock_stat() call in test_no_sockets MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit In `test_no_sockets` we don't expect any sockets, indeed check_no_sockets() prints an error and exits if `sockets` list is not empty, so free_sock_stat() call is unnecessary since it would only be called when the `sockets` list is empty. This was discovered by a strange warning printed by gcc v11.2.1: In file included from ../../include/linux/list.h:7, from vsock_diag_test.c:18: vsock_diag_test.c: In function ‘test_no_sockets’: ../../include/linux/kernel.h:35:45: error: array subscript ‘struct vsock_stat[0]’ is partly outside array bound s of ‘struct list_head[1]’ [-Werror=array-bounds] 35 | const typeof(((type *)0)->member) * __mptr = (ptr); \ | ^~~~~~ ../../include/linux/list.h:352:9: note: in expansion of macro ‘container_of’ 352 | container_of(ptr, type, member) | ^~~~~~~~~~~~ ../../include/linux/list.h:393:9: note: in expansion of macro ‘list_entry’ 393 | list_entry((pos)->member.next, typeof(*(pos)), member) | ^~~~~~~~~~ ../../include/linux/list.h:522:21: note: in expansion of macro ‘list_next_entry’ 522 | n = list_next_entry(pos, member); \ | ^~~~~~~~~~~~~~~ vsock_diag_test.c:325:9: note: in expansion of macro ‘list_for_each_entry_safe’ 325 | list_for_each_entry_safe(st, next, sockets, list) { | ^~~~~~~~~~~~~~~~~~~~~~~~ In file included from vsock_diag_test.c:18: vsock_diag_test.c:333:19: note: while referencing ‘sockets’ 333 | LIST_HEAD(sockets); | ^~~~~~~ ../../include/linux/list.h:23:26: note: in definition of macro ‘LIST_HEAD’ 23 | struct list_head name = LIST_HEAD_INIT(name) It seems related to some compiler optimization and assumption about the empty `sockets` list, since this warning is printed only with -02 or -O3. Also removing `exit(1)` from check_no_sockets() makes the warning disappear since in that case free_sock_stat() can be reached also when the list is not empty. Reported-by: Marc-André Lureau Signed-off-by: Stefano Garzarella Link: https://lore.kernel.org/r/20211014152045.173872-1-sgarzare@redhat.com Signed-off-by: Jakub Kicinski --- tools/testing/vsock/vsock_diag_test.c | 2 -- 1 file changed, 2 deletions(-) diff --git a/tools/testing/vsock/vsock_diag_test.c b/tools/testing/vsock/vsock_diag_test.c index cec6f5a738e1..fa927ad16f8a 100644 --- a/tools/testing/vsock/vsock_diag_test.c +++ b/tools/testing/vsock/vsock_diag_test.c @@ -332,8 +332,6 @@ static void test_no_sockets(const struct test_opts *opts) read_vsock_stat(&sockets); check_no_sockets(&sockets); - - free_sock_stat(&sockets); } static void test_listen_socket_server(const struct test_opts *opts)