/* -*- mode: c; c-basic-offset: 8; -*-
* vim: noexpandtab sw=8 ts=8 sts=0:
*
* slotmap.h
*
* description here
*
* Copyright (C) 2002, 2004 Oracle. All rights reserved.
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public
* License as published by the Free Software Foundation; either
* version 2 of the License, or (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* General Public License for more details.
*
* You should have received a copy of the GNU General Public
* License along with this program; if not, write to the
* Free Software Foundation, Inc., 59 Temple Place - Suite 330,
* Boston, MA 021110-1307, USA.
*/
#ifndef SLOTMAP_H
#define SLOTMAP_H
int ocfs2_init_slot_info(struct ocfs2_super *osb);
void ocfs2_free_slot_info(struct ocfs2_super *osb);
int ocfs2_find_slot(struct ocfs2_super *osb);
void ocfs2_put_slot(struct ocfs2_super *osb);
int ocfs2_refresh_slot_info(struct ocfs2_super *osb);
int ocfs2_node_num_to_slot(struct ocfs2_super *osb, unsigned int node_num);
int ocfs2_slot_to_node_num_locked(struct ocfs2_super *osb, int slot_num,
unsigned int *node_num);
int ocfs2_clear_slot(struct ocfs2_super *osb, int slot_num);
#endif
cgroup: don't online subsystems before cgroup_name/path() are operational
While refactoring cgroup creation, a5bca2152036 ("cgroup: factor out
cgroup_create() out of cgroup_mkdir()") incorrectly onlined subsystems
before the new cgroup is associated with it kernfs_node. This is fine
for cgroup proper but cgroup_name/path() depend on the associated
kernfs_node and if a subsystem makes the new cgroup_subsys_state
visible, which they're allowed to after onlining, it can lead to NULL
dereference.
The current code performs cgroup creation and subsystem onlining in
cgroup_create() and cgroup_mkdir() makes the cgroup and subsystems
visible afterwards. There's no reason to online the subsystems early
and we can simply drop cgroup_apply_control_enable() call from
cgroup_create() so that the subsystems are onlined and made visible at
the same time.
Signed-off-by: Tejun Heo <tj@kernel.org>
Reported-by: Konstantin Khlebnikov <khlebnikov@yandex-team.ru>
Fixes: a5bca2152036 ("cgroup: factor out cgroup_create() out of cgroup_mkdir()")
Cc: stable@vger.kernel.org # v4.6+