Re: [PATCH v12 05/14] x86/sgx: Implement basic EPC misc cgroup functionality

[Huang, Kai]

> Documentation of task_get_css() says it always  
> returns a valid css. This function is used by get_current_misc_cg() to get  
> the css refernce.
> 
> 
> /**
>   * task_get_css - find and get the css for (task, subsys)
>   * @task: the target task
>   * @subsys_id: the target subsystem ID
>   *
>   * Find the css for the (@task, @subsys_id) combination, increment a
>   * reference on and return it.  This function is guaranteed to return a
>   * valid css.  The returned css may already have been offlined.
>   */
> static inline struct cgroup_subsys_state *
> task_get_css(struct task_struct *task, int subsys_id)

Ah, I missed this comment.

This confirms my code reading too.

> 
> 
> If you look at the code of this function, you will see it does not check  
> NULL either for task_css().
> 
> So I think we are pretty sure here it's confirmed by this documentation  
> and testing.

Yeah agreed.  Thanks.