From b4535b58ae0df8b7cf0fe92a0c23aa3cf862e3cc Mon Sep 17 00:00:00 2001 From: =?utf8?q?Radim=20Kr=C4=8Dm=C3=A1=C5=99?= Date: Thu, 15 Dec 2016 18:06:47 +0100 Subject: [PATCH] KVM: x86: make interrupt delivery fast and slow path behave the same MIME-Version: 1.0 Content-Type: text/plain; charset=utf8 Content-Transfer-Encoding: 8bit Slow path tried to prevent IPIs from x2APIC VCPUs from being delivered to xAPIC VCPUs and vice-versa. Make slow path behave like fast path, which never distinguished that. Reviewed-by: David Hildenbrand Signed-off-by: Radim Krčmář Signed-off-by: Paolo Bonzini --- arch/x86/kvm/lapic.c | 20 ++++++++------------ 1 file changed, 8 insertions(+), 12 deletions(-) diff --git a/arch/x86/kvm/lapic.c b/arch/x86/kvm/lapic.c index 7c142f0fe9fd..3ebef53d20a0 100644 --- a/arch/x86/kvm/lapic.c +++ b/arch/x86/kvm/lapic.c @@ -592,10 +592,8 @@ static void apic_set_tpr(struct kvm_lapic *apic, u32 tpr) static bool kvm_apic_broadcast(struct kvm_lapic *apic, u32 mda) { - if (apic_x2apic_mode(apic)) - return mda == X2APIC_BROADCAST; - - return GET_APIC_DEST_FIELD(mda) == APIC_BROADCAST; + return mda == (apic_x2apic_mode(apic) ? + X2APIC_BROADCAST : APIC_BROADCAST); } static bool kvm_apic_match_physical_addr(struct kvm_lapic *apic, u32 mda) @@ -606,7 +604,7 @@ static bool kvm_apic_match_physical_addr(struct kvm_lapic *apic, u32 mda) if (apic_x2apic_mode(apic)) return mda == kvm_x2apic_id(apic); - return mda == SET_APIC_DEST_FIELD(kvm_xapic_id(apic)); + return mda == kvm_xapic_id(apic); } static bool kvm_apic_match_logical_addr(struct kvm_lapic *apic, u32 mda) @@ -623,7 +621,6 @@ static bool kvm_apic_match_logical_addr(struct kvm_lapic *apic, u32 mda) && (logical_id & mda & 0xffff) != 0; logical_id = GET_APIC_LOGICAL_ID(logical_id); - mda = GET_APIC_DEST_FIELD(mda); switch (kvm_lapic_get_reg(apic, APIC_DFR)) { case APIC_DFR_FLAT: @@ -640,9 +637,9 @@ static bool kvm_apic_match_logical_addr(struct kvm_lapic *apic, u32 mda) /* The KVM local APIC implementation has two quirks: * - * - the xAPIC MDA stores the destination at bits 24-31, while this - * is not true of struct kvm_lapic_irq's dest_id field. This is - * just a quirk in the API and is not problematic. + * - Real hardware delivers interrupts destined to x2APIC ID > 0xff to LAPICs + * in xAPIC mode if the "destination & 0xff" matches its xAPIC ID. + * KVM doesn't do that aliasing. * * - in-kernel IOAPIC messages have to be delivered directly to * x2APIC, because the kernel does not support interrupt remapping. @@ -658,13 +655,12 @@ static u32 kvm_apic_mda(struct kvm_vcpu *vcpu, unsigned int dest_id, struct kvm_lapic *source, struct kvm_lapic *target) { bool ipi = source != NULL; - bool x2apic_mda = apic_x2apic_mode(ipi ? source : target); if (!vcpu->kvm->arch.x2apic_broadcast_quirk_disabled && - !ipi && dest_id == APIC_BROADCAST && x2apic_mda) + !ipi && dest_id == APIC_BROADCAST && apic_x2apic_mode(target)) return X2APIC_BROADCAST; - return x2apic_mda ? dest_id : SET_APIC_DEST_FIELD(dest_id); + return dest_id; } bool kvm_apic_match_dest(struct kvm_vcpu *vcpu, struct kvm_lapic *source, -- 2.20.1