Tetsuo Handa 5db17805b6 cgroup: Add missing cpus_read_lock() to cgroup_attach_task_all()
commit 43626dade36fa74d3329046f4ae2d7fdefe401c6 upstream.

syzbot is hitting percpu_rwsem_assert_held(&cpu_hotplug_lock) warning at
cpuset_attach() [1], for commit 4f7e7236435ca0ab ("cgroup: Fix
threadgroup_rwsem <-> cpus_read_lock() deadlock") missed that
cpuset_attach() is also called from cgroup_attach_task_all().
Add cpus_read_lock() like what cgroup_procs_write_start() does.

Link: https://syzkaller.appspot.com/bug?extid=29d3a3b4d86c8136ad9e [1]
Reported-by: syzbot <syzbot+29d3a3b4d86c8136ad9e@syzkaller.appspotmail.com>
Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Fixes: 4f7e7236435ca0ab ("cgroup: Fix threadgroup_rwsem <-> cpus_read_lock() deadlock")
Signed-off-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-09-23 14:15:52 +02:00
..
2021-09-02 13:00:15 -07:00
2021-09-08 15:32:35 -07:00
2021-06-18 11:43:08 +02:00
2021-09-08 15:32:34 -07:00
2021-05-07 00:26:33 -07:00
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