[uml-devel] Re: Race condition in ptrace

[Nick P. <nic...@ya...>]

Bodo Stroesser wrote:
> Nick Piggin wrote:
> 
>> Bodo Stroesser wrote:

>> I don't see how this could help because AFAIKS, child->saving is only
>> set and cleared while the runqueue is locked. And the same runqueue lock
>> is taken by wait_task_inactive.
>>
> 
> Sorry, that not right. There are some routines called by sched(), that 
> release
> and reacquire the runqueue lock.
> 

Oh yeah, it is the wake_sleeping_dependent / dependent_sleeper crap.
Sorry, you are right. And that's definitely a bug in sched.c, because
it breaks wait_task_inactive, as you've rightly observed.

Andrew, IMO this is another bug to hold 2.6.11 for.