Re: [PATCH] memcg: fix oops in mem_cgroup_shrink_usage

Balbir Singh
2008-08-06T16:22:33Z

Hugh Dickins wrote:
> Got an oops in mem_cgroup_shrink_usage() when testing loop over tmpfs:
> yes, of course, loop0 has no mm: other entry points check but this didn't.
>
> Signed-off-by: Hugh Dickins <hugh@veritas.com>
> ---
>
> mm/memcontrol.c | 2 ++
> 1 file changed, 2 insertions(+)
>
> --- 2.6.27-rc2/mm/memcontrol.c 2008-08-06 08:36:20.000000000 +0100
> +++ linux/mm/memcontrol.c 2008-08-06 09:05:26.000000000 +0100
> @@ -796,6 +796,8 @@ int mem_cgroup_shrink_usage(struct mm_st
>
> if (mem_cgroup_subsys.disabled)
> return 0;
> + if (!mm)
> + return 0;
>
> rcu_read_lock();
> mem = mem_cgroup_from_task(rcu_dereference(mm->owner));

Looks good

Acked-by: Balbir Singh <balbir@linux.vnet.ibm.com>

--
Warm Regards,
Balbir Singh
Linux Technology Center
IBM, ISTL