Re: [PATCH -mm] PM: Prevent frozen user mode helpers from failing the freezing of tasks

[Oleg Nesterov]

On 06/25, Rafael J. Wysocki wrote:
>
> On Monday, 25 June 2007 12:43, Oleg Nesterov wrote:
> 
> > Second, call_usermodehelper's path should first increment the counter, and only
> > then check usermodehelper_disabled,
> 
> It does this already.

Ah, sorry, I looked at this patch without seeing the underlying code.

BTW, isn't it better to rename new_helper/helper_finished to
helper_lock/helper_unlock ?

> If I understand that correctly, it should suffice to place smp_mb() after
> usermodehelper_disabled = 1; in usermodehelper_pm_callback() and another
> smp_mb() after atomic_inc(&running_helpers); in new_helper().
> 
> Is that correct?

Afaics, yes.

Oleg.

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