From: "Pan, Jacob jun" <jacob.jun.pan@intel.com>
To: "Eric W. Biederman" <ebiederm@xmission.com>, Ingo Molnar <mingo@elte.hu>
CC: Jeremy Fitzhardinge <jeremy@goop.org>,
       "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
       "H. Peter Anvin" <hpa@linux.intel.com>
Date: Fri, 26 Jun 2009 13:59:02 -0700
Subject: RE: [PATCH 8/9] x86/apic: match destination id with destination mode
Thread-Topic: [PATCH 8/9] x86/apic: match destination id with destination
 mode
Thread-Index: Acn2l/afl49OjUQqSfmTDpWfPVPjeQAB1M7Q
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References: <43F901BD926A4E43B106BF17856F07556412B7E7@orsmsx508.amr.corp.intel.com>
	<20090626071725.GE14078@elte.hu> <m1hby293fh.fsf@fess.ebiederm.org>
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>Ingo Molnar <mingo@elte.hu> writes:
>
>> The question here is whether this should layer on top of Jeremy's
>> IO-APIC driverization patches. I think it should.
>
>The patch is a bad hack that is totally misdocumented.  A bit
>like the Xen apic changes in that respect.
>
>I haven't seen Jeremy's IO-APIC driverization patches.
>
>I am stumped why we need any driverization in this area.  x86_64 and has
>had for years a mechanism that is perfectly fine for abstracting this.
>i386 also has had something similar and last I looked we just about
>had that code merged.
>
>Xen doesn't have ioapics so it doesn't need us faking writes to
>ioapics.  Xen either needs to parse the ioapic tables itself
>or Xen needs a proper interface to be given the table information.
>
>I this patch can be replaced by a 2 line change to the apic mode
>logic to force us into physflat mode on moorestown.
>
>Eric
>

[[JPAN]] For Moorestown production silicon, we will use apic_default which uses
 logical dest mode. This patch is not required.
But, I think it is wrong to assign destination ID without looking at the mode 
bit. If we have a new apic_xxxx with phy dest mode, we would have logical APIC 
ID assigned to physical mode.
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