Messages in this thread | | | Date | Fri, 25 Jan 2008 23:11:05 +0100 | From | Pavel Machek <> | Subject | Re: [PATCH] x86: Construct 32 bit boot time page tables in native format. |
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Hi!
> > > >>I just looked at the ACPI suspend code, and it looks > > > >>like it hacks its own identity map at runtime. Pavel, > > > >>am I reading that code right? > > > > > > > >Yes, I think so, I believe we do it on both 32 and 64 > > > >bit now. > > > > > > > > > > So the background to this... we need an identity map to > > > trampoline at early boot, obviously, but we'd like it to > > > not stick around more than necessary. We have > > > zap_low_mappings() now but it's not really sufficient. > > > > > > Secondary SMP processors need these mappings during > > > trampolining -- presumably including CPU hotplug -- and > > > I'm suspecting it might simply make sense to use a > > > separate set of page tables (with both the identity and > > > the kernel map) for trampolining and just keep them > > > around. That way they would be usable for ACPI as well. > > > > That would enable some cleanups, yes. > > Speaking of cleanups, the following one is applicable IMO.
ACK... and BTW ack for that deferred device removal series.
Pavel -- (english) http://www.livejournal.com/~pavelmachek (cesky, pictures) http://atrey.karlin.mff.cuni.cz/~pavel/picture/horses/blog.html
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