Return-Path: linux-nfs-owner@vger.kernel.org Received: from mx1.redhat.com ([209.132.183.28]:20124 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753552Ab3FKLJn (ORCPT ); Tue, 11 Jun 2013 07:09:43 -0400 From: Jeff Layton To: viro@zeniv.linux.org.uk, matthew@wil.cx, bfields@fieldses.org Cc: dhowells@redhat.com, sage@inktank.com, smfrench@gmail.com, swhiteho@redhat.com, Trond.Myklebust@netapp.com, akpm@linux-foundation.org, linux-kernel@vger.kernel.org, linux-afs@lists.infradead.org, ceph-devel@vger.kernel.org, linux-cifs@vger.kernel.org, samba-technical@lists.samba.org, cluster-devel@redhat.com, linux-nfs@vger.kernel.org, linux-fsdevel@vger.kernel.org, piastryyy@gmail.com Subject: [PATCH v2 06/14] locks: don't walk inode->i_flock list in locks_show Date: Tue, 11 Jun 2013 07:09:00 -0400 Message-Id: <1370948948-31784-7-git-send-email-jlayton@redhat.com> In-Reply-To: <1370948948-31784-1-git-send-email-jlayton@redhat.com> References: <1370948948-31784-1-git-send-email-jlayton@redhat.com> Sender: linux-nfs-owner@vger.kernel.org List-ID: When we convert over to using the i_lock to protect the i_flock list, that will introduce a potential lock inversion problem in locks_show. When we want to walk the i_flock list, we'll need to take the i_lock. Rather than do that, just walk the global blocked_locks list and print out any that are blocked on the given lock. Signed-off-by: Jeff Layton --- fs/locks.c | 6 ++++-- 1 files changed, 4 insertions(+), 2 deletions(-) diff --git a/fs/locks.c b/fs/locks.c index e451d18..3fd27f0 100644 --- a/fs/locks.c +++ b/fs/locks.c @@ -2249,8 +2249,10 @@ static int locks_show(struct seq_file *f, void *v) lock_get_status(f, fl, *((loff_t *)f->private), ""); - list_for_each_entry(bfl, &fl->fl_block, fl_block) - lock_get_status(f, bfl, *((loff_t *)f->private), " ->"); + list_for_each_entry(bfl, &blocked_list, fl_link) { + if (bfl->fl_next == fl) + lock_get_status(f, bfl, *((loff_t *)f->private), " ->"); + } return 0; } -- 1.7.1