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[Xen-devel] x2apic mode vs. interrupt remapping

To: "Dexuan Cui" <dexuan.cui@xxxxxxxxx>
Subject: [Xen-devel] x2apic mode vs. interrupt remapping
From: "Jan Beulich" <JBeulich@xxxxxxxxxx>
Date: Wed, 03 Mar 2010 13:12:08 +0000
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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

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