Re: [PATCH] Use x2apic_supported() in the default_apic_id_valid()function.

From: Steffen Persvold
Date: Thu Mar 15 2012 - 19:44:26 EST


On 3/16/2012 00:33, Steffen Persvold wrote:
On 3/16/2012 00:04, Suresh Siddha wrote:
On Thu, 2012-03-15 at 23:34 +0100, Steffen Persvold wrote:
Is my understanding of your suggestion correct that in
x2apic_phys/cluster.c we add the following apic_id_valid() function :

static int x2apic_apic_id_valid(int apicid)
{
return x2apic_mode || (apicid< 255);
}

Steffen, We can have something like:

static int x2apic_apic_id_valid(int apicid)
{
return 1;
}

and

static int xapic_apic_id_valid(int apicid)
{
return apicid< 255;
}

If we have selected x2apic driver, then we know we are already in x2apic
mode. And also x2apic_uv_x need to use the x2apic version above.


If you specify "nox2apic" option, will it choose the xapic driver
instead (and early enough) ? Otherwise I think we might break Yinghai's
commit (a35fd28256e7736cc84af8931a16224f0bfaaf6c).


Answering myself here, my apologies, but yes it looks like both x2apic drivers will be de-activated if the "nox2apic" option is specified (x2apic_enabled() will return false).


Cheers,
Steffen
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