From mboxrd@z Thu Jan  1 00:00:00 1970
From: Jan Kiszka <jan.kiszka@siemens.com>
Subject: Re: APIC_ID in apic_reg_write()
Date: Wed, 29 Apr 2015 20:34:27 +0200
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To: Bandan Das <bsd@redhat.com>, kvm@vger.kernel.org
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Am 2015-04-29 um 18:47 schrieb Bandan Das:
> 
> Why do we allow writes to APIC_ID ? On all _newer_ processors, it's
> read only. The spec doesn't explicitly mention it though, or atleast
> I couldn't find it. Does userspace have a reason to modify it ?

The APIC ID is read-only for x2APIC. It remains R/W for xAPIC.

Jan

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