Re: [PATCH 2/6] x86: apic - unify lapic_resume

From: Cyrill Gorcunov
Date: Sat Aug 16 2008 - 16:12:37 EST


[Arjan van de Ven - Sat, Aug 16, 2008 at 01:00:08PM -0700]
| On Sat, 16 Aug 2008 20:52:07 +0100 (BST)
| "Maciej W. Rozycki" <macro@xxxxxxxxxxxxxx> wrote:
|
| > On Sat, 16 Aug 2008, Cyrill Gorcunov wrote:
| >
| > > +#ifdef CONFIG_X86_64
| > > + if (x2apic)
| > > + enable_x2apic();
| > > + else
| > > +#endif
| >
| > Hmm, x86-64 hardware can run a 32-bit kernel, so it might be a good
| > idea to take the opportunity of the merge and extend x2APIC support
| > to the 32-bit configuration too. It should be mostly a mechanical
| > change. Just a suggestion though -- feel free to ignore if you'd
| > rather not dive into it. ;)
|
| it's not like you can/want to go over 128 cpus on a 32 bit kernel
| though..
| --
| If you want to reach me at my work email, use arjan@xxxxxxxxxxxxxxx
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|

Arjan,

it seems this limit is not APIC related since iirc 82489DX allows
to address 2^14 bits, x2APIC - more then 128 entities too. So I suspect
it somehow cpu bitmap related. Am I wrong (I didn't _check_ the code)?

- Cyrill -
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