From: Herton Ronaldo Krzesinski Subject: [PATCH] ext4: remove static from struct match_token used in token2str Date: Fri, 21 Sep 2012 22:21:00 -0300 Message-ID: <1348276860-21705-1-git-send-email-herton.krzesinski@canonical.com> Cc: Andreas Dilger , linux-ext4@vger.kernel.org, linux-kernel@vger.kernel.org To: Theodore Ts'o Return-path: Received: from youngberry.canonical.com ([91.189.89.112]:55883 "EHLO youngberry.canonical.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752542Ab2IVBVH (ORCPT ); Fri, 21 Sep 2012 21:21:07 -0400 Sender: linux-ext4-owner@vger.kernel.org List-ID: There is no reason to use static there, and it will cause issues when reading /proc/fs/ext4//options concurrently. Signed-off-by: Herton Ronaldo Krzesinski Cc: stable@vger.kernel.org # 3.4+ --- fs/ext4/super.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) The problem is easy to reproduce, for example running: $ cat /proc/fs/ext4//options > options.txt $ while diff /proc/fs/ext4//options options.txt; do true; done - And concurrently on another terminal: $ while diff /proc/fs/ext4//options options.txt; do true; done One of the diff loops will get incomplete options contents because of the issue, and exit. I also believe the same problem is the cause of the following bug: https://bugs.launchpad.net/bugs/1053019, that happened while running test 234 from xfstests. diff --git a/fs/ext4/super.c b/fs/ext4/super.c index 41598ee..975405c 100644 --- a/fs/ext4/super.c +++ b/fs/ext4/super.c @@ -1748,7 +1748,7 @@ static inline void ext4_show_quota_options(struct seq_file *seq, static const char *token2str(int token) { - static const struct match_token *t; + const struct match_token *t; for (t = tokens; t->token != Opt_err; t++) if (t->token == token && !strchr(t->pattern, '=')) -- 1.7.9.5