From mboxrd@z Thu Jan  1 00:00:00 1970
From: "Jan Beulich" <JBeulich@novell.com>
Subject: x2apic mode vs. interrupt remapping
Date: Wed, 03 Mar 2010 13:12:08 +0000
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To: Dexuan Cui <dexuan.cui@intel.com>
Cc: xen-devel@lists.xensource.com
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Hi,

while the Linux kernel enters x2apic mode only when it was able to
initialize interrupt remapping (leaving aside a KVM special case), Xen
treats the two features as independent ones. We're having a report
where interrupt delivery doesn't work in x2apic mode (i.e. no-x2apic
makes the system boot successfully), and hence I'm wondering why
Xen would use this mode on a wider range of machines than Linux.

Thanks, Jan