KVM: x86: some apic broadcast modes does not work
KVM does not deliver x2APIC broadcast messages with physical mode. Intel SDM (10.12.9 ICR Operation in x2APIC Mode) states: "A destination ID value of FFFF_FFFFH is used for broadcast of interrupts in both logical destination and physical destination modes." In addition, the local-apic enables cluster mode broadcast. As Intel SDM 10.6.2.2 says: "Broadcast to all local APICs is achieved by setting all destination bits to one." This patch enables cluster mode broadcast. The fix tries to combine broadcast in different modes through a unified code. One rare case occurs when the source of IPI has its APIC disabled. In such case, the source can still issue IPIs, but since the source is not obliged to have the same LAPIC mode as the enabled ones, we cannot rely on it. Since it is a rare case, it is unoptimized and done on the slow-path. Signed-off-by:Nadav Amit <namit@cs.technion.ac.il> Reviewed-by:
Radim Krčmář <rkrcmar@redhat.com> Reviewed-by:
Wanpeng Li <wanpeng.li@linux.intel.com> [As per Radim's review, use unsigned int for X2APIC_BROADCAST, return bool from kvm_apic_broadcast. - Paolo] Signed-off-by:
Paolo Bonzini <pbonzini@redhat.com>
parent
52ce3c21
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