Re: possible deadlock in start_this_handle (2)

[Tetsuo Handa]

On 2021/02/12 1:41, Michal Hocko wrote:
> But I suspect we have drifted away from the original issue. I thought
> that a simple check would help us narrow down this particular case and
> somebody messing up from the IRQ context didn't sound like a completely
> off.
> 

 From my experience at https://lkml.kernel.org/r/201409192053.IHJ35462.JLOMOSOFFVtQFH@xxxxxxxxxxxxxxxxxxx ,
I think we can replace direct PF_* manipulation with macros which do not receive "struct task_struct *" argument.
Since TASK_PFA_TEST()/TASK_PFA_SET()/TASK_PFA_CLEAR() are for manipulating PFA_* flags on a remote thread, we can
define similar ones for manipulating PF_* flags on current thread. Then, auditing dangerous users becomes easier.