Re: [PATCH v3 00/13] Virtually mapped stacks with guard pages (x86, core)

[Peter Zijlstra]

On Thu, Jun 23, 2016 at 08:12:16PM +0200, Oleg Nesterov wrote:
> 
> And probably kill task_struct->blocked_on? I do not see the point of
> this task->blocked_on != waiter check.

I think that came about because of PI and or deadlock detection. Of
course, the current mutex code doesn't have anything like that these
days, and rt_mutex has task_struct::pi_blocked_on.