From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755160AbcCBCJX (ORCPT ); Tue, 1 Mar 2016 21:09:23 -0500 Received: from mail.linuxfoundation.org ([140.211.169.12]:45938 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753399AbcCAXr3 (ORCPT ); Tue, 1 Mar 2016 18:47:29 -0500 From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Al Viro Subject: [PATCH 3.14 025/130] lift the "already marked killed" case into shrink_dentry_list() Date: Tue, 1 Mar 2016 15:44:36 -0800 Message-Id: <20160301234500.655332721@linuxfoundation.org> X-Mailer: git-send-email 2.7.2 In-Reply-To: <20160301234459.768886030@linuxfoundation.org> References: <20160301234459.768886030@linuxfoundation.org> User-Agent: quilt/0.64 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 3.14-stable review patch. If anyone has any objections, please let me know. ------------------ From: Al Viro commit 64fd72e0a44bdd62c5ca277cb24d0d02b2d8e9dc upstream. It can happen only when dentry_kill() is called with unlock_on_failure equal to 0 - other callers had dentry pinned until the moment they've got ->d_lock and DCACHE_DENTRY_KILLED is set only after lockref_mark_dead(). IOW, only one of three call sites of dentry_kill() might end up reaching that code. Just move it there. Signed-off-by: Al Viro Signed-off-by: Greg Kroah-Hartman --- fs/dcache.c | 15 +++++++++------ 1 file changed, 9 insertions(+), 6 deletions(-) --- a/fs/dcache.c +++ b/fs/dcache.c @@ -453,12 +453,6 @@ dentry_kill(struct dentry *dentry, int u struct dentry *parent = NULL; bool can_free = true; - if (unlikely(dentry->d_flags & DCACHE_DENTRY_KILLED)) { - can_free = dentry->d_flags & DCACHE_MAY_FREE; - spin_unlock(&dentry->d_lock); - goto out; - } - inode = dentry->d_inode; if (inode && !spin_trylock(&inode->i_lock)) { relock: @@ -816,6 +810,15 @@ static void shrink_dentry_list(struct li continue; } + + if (unlikely(dentry->d_flags & DCACHE_DENTRY_KILLED)) { + bool can_free = dentry->d_flags & DCACHE_MAY_FREE; + spin_unlock(&dentry->d_lock); + if (can_free) + dentry_free(dentry); + continue; + } + parent = dentry_kill(dentry, 0); /* * If dentry_kill returns NULL, we have nothing more to do.