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

Pavel Machek
2006-06-15T20:03:34Z

Hi!

> > Okay, console switches are really needed -- so that X gets it chance
> > to save graphics state. Try your version from accelerated X -- it
> > would break AFAICS.
> >
> > So we basically need the old code -- to switch consoles -- and then
> > your new code -- to prevent writing to console that is suspended.
>
> No.
>
> You're DOING THE SAME MISTAKE AGAIN!
>
> You're confusing "shutdown" with "save state". The two are totally
> separate, and they MUST be separate. Trying to combine the two is wrong,
> wrong, wrong.
>
> Repeat after me: we must save the state of a device before we shut _any_
> device down.

Why? We are saving state to memory, we should not need any other
devices to do that.

Well, for devices that are so complex that userspace support is
needed... yes, you are right, separate pass would be
needed. Fortunately, such devices are not too common.

> That is as true for X and the console as it is for _any_ other device.
>
> So it's a slight improvement (because now the functions are at least
> separate), but by putting the console state saving in the path that does
> the suspend, you're again mixing up the issue of suspending the devices,
> and actually saving their state.
>
> The console switch itself is actually wrong, but at least it works (we
> should just initiate the "give me back the console" part, not the actual
> _switching_, but that would require some cleanup in vt_ioctl.c), but the
> _position_ is wrong.

Well, doing half-switch would be cleaner in s2ram case, agreed. For
s2disk, having console to write on is actually very nice.

Pavel
--
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