Re: fixing usb suspend/resuming

[Pavel Machek]

Hi!

> > Well, its more complicated, I believe. You can't just leave those
> > devices running, because they could DMA and damage the image... So you
> 
> I'm assuming (and believe I have achieved) that the only process doing
> anything significant is suspend, in which case the image isn't going to
> get damaged.

Well, only suspend is doing something significant, but driver might
take arbitrary time to do its DMA... Like

Freeing some memory... [write starts]
Suspending devices... [but you did not suspend disk!]
Atomic copy... [oops, that disk was *still* doing DMA]

> > need something like
> > 
> > suspend_fast_ill_resume_you_soon().
> 
> Don't understand what you're saying here, sorry.

Well, I believe we really need to suspend *all* devices. We just do
not need to spin the disks down and make screens blank; we still need
drivers to be stopped so that no activity happens during atomic copy.

								Pavel
-- 
People were complaining that M$ turns users into beta-testers...
...jr ghea gurz vagb qrirybcref, naq gurl frrz gb yvxr vg gung jnl!
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