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Date: Tue, 07 May 2013 18:46:43 +0800
From: Chen Gang <gang.chen@asianux.com>
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To: tj@kernel.org, Li Zefan <lizefan@huawei.com>
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Subject: [Suggestion] kernel/cgroup.c: about kfree after 'get_new_cssid'
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Hello Maintainers:

After call get_new_cssid(), I can not find the related free function
(it seems free_css_id() is for that, but not used).

The memory location is:
  get_new_cssid() --> kzalloc() for 'struct css_id'
  get_new_cssid() --> idr_alloc() for 'ss->idr'

One work flow:
  cgroup_load_subsys() --> cgroup_init_idr() --> get_new_cssid()
  when get_new_cssid() fails, it will:
  cgroup_load_subsys() --> cgroup_unload_subsys() --> idr_destroy(),
  and also:
  cgroup_load_subsys() --> cgroup_unload_subsys() --> ss->css_free();
    ('css_free' may 'debug_css_free', or 'freezer_css_free' ...)

It seems the work flow above is not 'kfree' 'struct css_id', is it true?

BTW: I also guess, for cgroup_init_idr() in cgroup_init(), need check
the return value.

Please help check.


Thanks.

--
 Chen Gang

 Asianux Corporation