From 9ea369b032d87b88f1a47187b51ad4321dea5766 Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Radim=20Kr=C4=8Dm=C3=A1=C5=99?= Date: Thu, 12 Feb 2015 19:41:32 +0100 Subject: KVM: x86: fix mixed APIC mode broadcast MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Broadcast allowed only one global APIC mode, but mixed modes are theoretically possible. x2APIC IPI doesn't mean 0xff as broadcast, the rest does. x2APIC broadcasts are accepted by xAPIC. If we take SDM to be logical, even addreses beginning with 0xff should be accepted, but real hardware disagrees. This patch aims for simple code by considering most of real behavior as undefined. Signed-off-by: Radim Krčmář Message-Id: <1423766494-26150-3-git-send-email-rkrcmar@redhat.com> Signed-off-by: Paolo Bonzini --- arch/x86/kvm/lapic.c | 9 ++++----- 1 file changed, 4 insertions(+), 5 deletions(-) (limited to 'arch/x86/kvm/lapic.c') diff --git a/arch/x86/kvm/lapic.c b/arch/x86/kvm/lapic.c index 69569744745d..d45f00ba7440 100644 --- a/arch/x86/kvm/lapic.c +++ b/arch/x86/kvm/lapic.c @@ -151,7 +151,6 @@ static void recalculate_apic_map(struct kvm *kvm) new->cid_shift = 8; new->cid_mask = 0; new->lid_mask = 0xff; - new->broadcast = APIC_BROADCAST; kvm_for_each_vcpu(i, vcpu, kvm) { struct kvm_lapic *apic = vcpu->arch.apic; @@ -163,7 +162,6 @@ static void recalculate_apic_map(struct kvm *kvm) new->ldr_bits = 32; new->cid_shift = 16; new->cid_mask = new->lid_mask = 0xffff; - new->broadcast = X2APIC_BROADCAST; } else if (kvm_apic_get_reg(apic, APIC_LDR)) { if (kvm_apic_get_reg(apic, APIC_DFR) == APIC_DFR_CLUSTER) { @@ -690,6 +688,7 @@ bool kvm_irq_delivery_to_apic_fast(struct kvm *kvm, struct kvm_lapic *src, struct kvm_lapic **dst; int i; bool ret = false; + bool x2apic_ipi = src && apic_x2apic_mode(src); *r = -1; @@ -701,15 +700,15 @@ bool kvm_irq_delivery_to_apic_fast(struct kvm *kvm, struct kvm_lapic *src, if (irq->shorthand) return false; + if (irq->dest_id == (x2apic_ipi ? X2APIC_BROADCAST : APIC_BROADCAST)) + return false; + rcu_read_lock(); map = rcu_dereference(kvm->arch.apic_map); if (!map) goto out; - if (irq->dest_id == map->broadcast) - goto out; - ret = true; if (irq->dest_mode == APIC_DEST_PHYSICAL) { -- cgit v1.2.1