Re: [PATCH 2/2] Fix console handling during suspend/resume

Benjamin Herrenschmidt
2006-06-24T00:29:27Z

> That's bullshit. How can USB operate without interrupts ? It can't. Thus
> the final suspend will not be useable for anything below a USB
> controller. Among others... That means that every driver that needs to
> talk to it's hardware will have to run with "interrupts off"... thus
> every driver will need some kind of demoted polled mode that they don't
> necessarily have.
>
> Thus your "final suspend" ends up only being useful for a small subset
> of drivers
>
> Also there is nothing magic about "interrupts have been turned off".
> It's no magic, it won't prevent everything from happening. How do you
> make sure you weren't in the middle of driver routine already ? You
> can't. Thus you need your driver to _also_ be able to recover of suspend
> being called at any fucking time while it was doing something and not be
> able to synchrnize with things like semaphores etc...

And the total non-applicability of this model to runtime suspend of
individual devices of course..

Ben.