1 files changed, 77 insertions, 17 deletions

diff --git a/arch/x86/kvm/lapic.c b/arch/x86/kvm/lapic.c
index 0cefba28c864..3cd227ff807f 100644
--- a/arch/x86/kvm/lapic.c
+++ b/arch/x86/kvm/lapic.c
@@ -70,6 +70,11 @@
 #define APIC_BROADCAST			0xFF
 #define X2APIC_BROADCAST		0xFFFFFFFFul
 
+static bool lapic_timer_advance_adjust_done = false;
+#define LAPIC_TIMER_ADVANCE_ADJUST_DONE 100
+/* step-by-step approximation to mitigate fluctuation */
+#define LAPIC_TIMER_ADVANCE_ADJUST_STEP 8
+
 static inline int apic_test_vector(int vec, void *bitmap)
 {
 	return test_bit(VEC_POS(vec), (bitmap) + REG_POS(vec));
@@ -548,7 +553,7 @@ int kvm_apic_set_irq(struct kvm_vcpu *vcpu, struct kvm_lapic_irq *irq,
 }
 
 int kvm_pv_send_ipi(struct kvm *kvm, unsigned long ipi_bitmap_low,
-    		    unsigned long ipi_bitmap_high, int min,
+		    unsigned long ipi_bitmap_high, u32 min,
 		    unsigned long icr, int op_64_bit)
 {
 	int i;
@@ -571,18 +576,31 @@ int kvm_pv_send_ipi(struct kvm *kvm, unsigned long ipi_bitmap_low,
 	rcu_read_lock();
 	map = rcu_dereference(kvm->arch.apic_map);
 
+	if (min > map->max_apic_id)
+		goto out;
 	/* Bits above cluster_size are masked in the caller.  */
-	for_each_set_bit(i, &ipi_bitmap_low, BITS_PER_LONG) {
-		vcpu = map->phys_map[min + i]->vcpu;
-		count += kvm_apic_set_irq(vcpu, &irq, NULL);
+	for_each_set_bit(i, &ipi_bitmap_low,
+		min((u32)BITS_PER_LONG, (map->max_apic_id - min + 1))) {
+		if (map->phys_map[min + i]) {
+			vcpu = map->phys_map[min + i]->vcpu;
+			count += kvm_apic_set_irq(vcpu, &irq, NULL);
+		}
 	}
 
 	min += cluster_size;
-	for_each_set_bit(i, &ipi_bitmap_high, BITS_PER_LONG) {
-		vcpu = map->phys_map[min + i]->vcpu;
-		count += kvm_apic_set_irq(vcpu, &irq, NULL);
+
+	if (min > map->max_apic_id)
+		goto out;
+
+	for_each_set_bit(i, &ipi_bitmap_high,
+		min((u32)BITS_PER_LONG, (map->max_apic_id - min + 1))) {
+		if (map->phys_map[min + i]) {
+			vcpu = map->phys_map[min + i]->vcpu;
+			count += kvm_apic_set_irq(vcpu, &irq, NULL);
+		}
 	}
 
+out:
 	rcu_read_unlock();
 	return count;
 }
@@ -942,14 +960,14 @@ bool kvm_irq_delivery_to_apic_fast(struct kvm *kvm, struct kvm_lapic *src,
 	map = rcu_dereference(kvm->arch.apic_map);
 
 	ret = kvm_apic_map_get_dest_lapic(kvm, &src, irq, map, &dst, &bitmap);
-	if (ret)
+	if (ret) {
+		*r = 0;
 		for_each_set_bit(i, &bitmap, 16) {
 			if (!dst[i])
 				continue;
-			if (*r < 0)
-				*r = 0;
 			*r += kvm_apic_set_irq(dst[i]->vcpu, irq, dest_map);
 		}
+	}
 
 	rcu_read_unlock();
 	return ret;
@@ -1331,9 +1349,8 @@ EXPORT_SYMBOL_GPL(kvm_lapic_reg_read);
 
 static int apic_mmio_in_range(struct kvm_lapic *apic, gpa_t addr)
 {
-	return kvm_apic_hw_enabled(apic) &&
-	    addr >= apic->base_address &&
-	    addr < apic->base_address + LAPIC_MMIO_LENGTH;
+	return addr >= apic->base_address &&
+		addr < apic->base_address + LAPIC_MMIO_LENGTH;
 }
 
 static int apic_mmio_read(struct kvm_vcpu *vcpu, struct kvm_io_device *this,
@@ -1345,6 +1362,15 @@ static int apic_mmio_read(struct kvm_vcpu *vcpu, struct kvm_io_device *this,
 	if (!apic_mmio_in_range(apic, address))
 		return -EOPNOTSUPP;
 
+	if (!kvm_apic_hw_enabled(apic) || apic_x2apic_mode(apic)) {
+		if (!kvm_check_has_quirk(vcpu->kvm,
+					 KVM_X86_QUIRK_LAPIC_MMIO_HOLE))
+			return -EOPNOTSUPP;
+
+		memset(data, 0xff, len);
+		return 0;
+	}
+
 	kvm_lapic_reg_read(apic, offset, len, data);
 
 	return 0;
@@ -1451,7 +1477,7 @@ static bool lapic_timer_int_injected(struct kvm_vcpu *vcpu)
 void wait_lapic_expire(struct kvm_vcpu *vcpu)
 {
 	struct kvm_lapic *apic = vcpu->arch.apic;
-	u64 guest_tsc, tsc_deadline;
+	u64 guest_tsc, tsc_deadline, ns;
 
 	if (!lapic_in_kernel(vcpu))
 		return;
@@ -1471,6 +1497,24 @@ void wait_lapic_expire(struct kvm_vcpu *vcpu)
 	if (guest_tsc < tsc_deadline)
 		__delay(min(tsc_deadline - guest_tsc,
 			nsec_to_cycles(vcpu, lapic_timer_advance_ns)));
+
+	if (!lapic_timer_advance_adjust_done) {
+		/* too early */
+		if (guest_tsc < tsc_deadline) {
+			ns = (tsc_deadline - guest_tsc) * 1000000ULL;
+			do_div(ns, vcpu->arch.virtual_tsc_khz);
+			lapic_timer_advance_ns -= min((unsigned int)ns,
+				lapic_timer_advance_ns / LAPIC_TIMER_ADVANCE_ADJUST_STEP);
+		} else {
+		/* too late */
+			ns = (guest_tsc - tsc_deadline) * 1000000ULL;
+			do_div(ns, vcpu->arch.virtual_tsc_khz);
+			lapic_timer_advance_ns += min((unsigned int)ns,
+				lapic_timer_advance_ns / LAPIC_TIMER_ADVANCE_ADJUST_STEP);
+		}
+		if (abs(guest_tsc - tsc_deadline) < LAPIC_TIMER_ADVANCE_ADJUST_DONE)
+			lapic_timer_advance_adjust_done = true;
+	}
 }
 
 static void start_sw_tscdeadline(struct kvm_lapic *apic)
@@ -1904,6 +1948,14 @@ static int apic_mmio_write(struct kvm_vcpu *vcpu, struct kvm_io_device *this,
 	if (!apic_mmio_in_range(apic, address))
 		return -EOPNOTSUPP;
 
+	if (!kvm_apic_hw_enabled(apic) || apic_x2apic_mode(apic)) {
+		if (!kvm_check_has_quirk(vcpu->kvm,
+					 KVM_X86_QUIRK_LAPIC_MMIO_HOLE))
+			return -EOPNOTSUPP;
+
+		return 0;
+	}
+
 	/*
 	 * APIC register must be aligned on 128-bits boundary.
 	 * 32/64/128 bits registers must be accessed thru 32 bits.
@@ -2592,17 +2644,25 @@ int kvm_hv_vapic_msr_read(struct kvm_vcpu *vcpu, u32 reg, u64 *data)
 	return 0;
 }
 
-int kvm_lapic_enable_pv_eoi(struct kvm_vcpu *vcpu, u64 data)
+int kvm_lapic_enable_pv_eoi(struct kvm_vcpu *vcpu, u64 data, unsigned long len)
 {
 	u64 addr = data & ~KVM_MSR_ENABLED;
+	struct gfn_to_hva_cache *ghc = &vcpu->arch.pv_eoi.data;
+	unsigned long new_len;
+
 	if (!IS_ALIGNED(addr, 4))
 		return 1;
 
 	vcpu->arch.pv_eoi.msr_val = data;
 	if (!pv_eoi_enabled(vcpu))
 		return 0;
-	return kvm_gfn_to_hva_cache_init(vcpu->kvm, &vcpu->arch.pv_eoi.data,
-					 addr, sizeof(u8));
+
+	if (addr == ghc->gpa && len <= ghc->len)
+		new_len = ghc->len;
+	else
+		new_len = len;
+
+	return kvm_gfn_to_hva_cache_init(vcpu->kvm, ghc, addr, new_len);
 }
 
 void kvm_apic_accept_events(struct kvm_vcpu *vcpu)