KVM: X86: Filter out the broadcast dest for IPI fastpath

Except destination shorthand, a destination value 0xffffffff is used to
broadcast interrupts, let's also filter out this for single target IPI
fastpath.

Reviewed-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Signed-off-by: Wanpeng Li <wanpengli@tencent.com>
Message-Id: <1585815626-28370-1-git-send-email-wanpengli@tencent.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

diff --git a/arch/x86/kvm/lapic.c b/arch/x86/kvm/lapic.c
index ca80daf..9af25c9 100644 (file)
--- a/arch/x86/kvm/lapic.c
+++ b/arch/x86/kvm/lapic.c
@@ -59,9 +59,6 @@
 #define MAX_APIC_VECTOR                        256
 #define APIC_VECTORS_PER_REG           32
 
-#define APIC_BROADCAST                 0xFF
-#define X2APIC_BROADCAST               0xFFFFFFFFul
-
 static bool lapic_timer_advance_dynamic __read_mostly;
 #define LAPIC_TIMER_ADVANCE_ADJUST_MIN 100     /* clock cycles */
 #define LAPIC_TIMER_ADVANCE_ADJUST_MAX 10000   /* clock cycles */

diff --git a/arch/x86/kvm/lapic.h b/arch/x86/kvm/lapic.h
index 40ed6ed..a0ffb43 100644 (file)
--- a/arch/x86/kvm/lapic.h
+++ b/arch/x86/kvm/lapic.h
@@ -17,6 +17,9 @@
 #define APIC_BUS_CYCLE_NS       1
 #define APIC_BUS_FREQUENCY      (1000000000ULL / APIC_BUS_CYCLE_NS)
 
+#define APIC_BROADCAST                 0xFF
+#define X2APIC_BROADCAST               0xFFFFFFFFul
+
 enum lapic_mode {
        LAPIC_MODE_DISABLED = 0,
        LAPIC_MODE_INVALID = X2APIC_ENABLE,

diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index b8124b5..027dfd2 100644 (file)
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -1586,7 +1586,8 @@ static int handle_fastpath_set_x2apic_icr_irqoff(struct kvm_vcpu *vcpu, u64 data
 
        if (((data & APIC_SHORT_MASK) == APIC_DEST_NOSHORT) &&
                ((data & APIC_DEST_MASK) == APIC_DEST_PHYSICAL) &&
-               ((data & APIC_MODE_MASK) == APIC_DM_FIXED)) {
+               ((data & APIC_MODE_MASK) == APIC_DM_FIXED) &&
+               ((u32)(data >> 32) != X2APIC_BROADCAST)) {
 
                data &= ~(1 << 12);
                kvm_apic_send_ipi(vcpu->arch.apic, (u32)data, (u32)(data >> 32));