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

Linus Torvalds
2006-06-16T03:22:52Z

On Fri, 16 Jun 2006, Nigel Cunningham wrote:
> >
> > You don't _need_ to save a consistent system image. There's no "single
> > snapshot in time" needed.
>
> Yes, you do. If you save an image that has, say, pages in the lru that are
> also in the free lists or a similar situation with driver data, you're going
> to get an oops some time after resume at best, and possibly ruin your
> filesystem at worst.

Absolutely. I've acknowledged this several times. But that's not a "device
state" thing, that's a MM state thing.

I 100% agree that we must have a consistent image of free memory after
resume. That's not in question at all. What I dispute is that this is
"device state" and has anything to do with suspending devices..

The fact that this only affects STD and not STR should make people realize
that it's not a "device" issue. STR suspends/resumes devices too, so if
STR doesn't have that issue, then clearly it's not actually tied to the
notion of device suspend/resume per se.

It's really not at all different from _any_ memory allocation after the
start of writing the image to memory, is it?

Linus