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gfiber / kernel / quantenna / 35749ef91b70b13b4955ec5efdef79549106c35f / . / arch / x86 / kvm / lapic.c
blob: a397200281c119aabb283fce45c4a921f3f4cd24 [file] [log] [blame]
/*
* Local APIC virtualization
*
* Copyright (C) 2006 Qumranet, Inc.
* Copyright (C) 2007 Novell
* Copyright (C) 2007 Intel
* Copyright 2009 Red Hat, Inc. and/or its affiliates.
*
* Authors:
* Dor Laor <dor.laor@qumranet.com>
* Gregory Haskins <ghaskins@novell.com>
* Yaozu (Eddie) Dong <eddie.dong@intel.com>
*
* Based on Xen 3.1 code, Copyright (c) 2004, Intel Corporation.
*
* This work is licensed under the terms of the GNU GPL, version 2. See
* the COPYING file in the top-level directory.
*/
#include <linux/kvm_host.h>
#include <linux/kvm.h>
#include <linux/mm.h>
#include <linux/highmem.h>
#include <linux/smp.h>
#include <linux/hrtimer.h>
#include <linux/io.h>
#include <linux/module.h>
#include <linux/math64.h>
#include <linux/slab.h>
#include <asm/processor.h>
#include <asm/msr.h>
#include <asm/page.h>
#include <asm/current.h>
#include <asm/apicdef.h>
#include <asm/delay.h>
#include <linux/atomic.h>
#include <linux/jump_label.h>
#include "kvm_cache_regs.h"
#include "irq.h"
#include "trace.h"
#include "x86.h"
#include "cpuid.h"
#include "hyperv.h"
#ifndef CONFIG_X86_64
#define mod_64(x, y) ((x) - (y) * div64_u64(x, y))
#else
#define mod_64(x, y) ((x) % (y))
#endif
#define PRId64 "d"
#define PRIx64 "llx"
#define PRIu64 "u"
#define PRIo64 "o"
#define APIC_BUS_CYCLE_NS 1
/* #define apic_debug(fmt,arg...) printk(KERN_WARNING fmt,##arg) */
#define apic_debug(fmt, arg...)
/* 14 is the version for Xeon and Pentium 8.4.8*/
#define APIC_VERSION (0x14UL | ((KVM_APIC_LVT_NUM - 1) << 16))
#define LAPIC_MMIO_LENGTH (1 << 12)
/* followed define is not in apicdef.h */
#define APIC_SHORT_MASK 0xc0000
#define APIC_DEST_NOSHORT 0x0
#define APIC_DEST_MASK 0x800
#define MAX_APIC_VECTOR 256
#define APIC_VECTORS_PER_REG 32
#define APIC_BROADCAST 0xFF
#define X2APIC_BROADCAST 0xFFFFFFFFul
static inline int apic_test_vector(int vec, void *bitmap)
{
return test_bit(VEC_POS(vec), (bitmap) + REG_POS(vec));
}
bool kvm_apic_pending_eoi(struct kvm_vcpu *vcpu, int vector)
{
struct kvm_lapic *apic = vcpu->arch.apic;
return apic_test_vector(vector, apic->regs + APIC_ISR) ||
apic_test_vector(vector, apic->regs + APIC_IRR);
}
static inline void apic_clear_vector(int vec, void *bitmap)
{
clear_bit(VEC_POS(vec), (bitmap) + REG_POS(vec));
}
static inline int __apic_test_and_set_vector(int vec, void *bitmap)
{
return __test_and_set_bit(VEC_POS(vec), (bitmap) + REG_POS(vec));
}
static inline int __apic_test_and_clear_vector(int vec, void *bitmap)
{
return __test_and_clear_bit(VEC_POS(vec), (bitmap) + REG_POS(vec));
}
struct static_key_deferred apic_hw_disabled __read_mostly;
struct static_key_deferred apic_sw_disabled __read_mostly;
static inline int apic_enabled(struct kvm_lapic *apic)
{
return kvm_apic_sw_enabled(apic) && kvm_apic_hw_enabled(apic);
}
#define LVT_MASK \
(APIC_LVT_MASKED | APIC_SEND_PENDING | APIC_VECTOR_MASK)
#define LINT_MASK \
(LVT_MASK | APIC_MODE_MASK | APIC_INPUT_POLARITY | \
APIC_LVT_REMOTE_IRR | APIC_LVT_LEVEL_TRIGGER)
/* The logical map is definitely wrong if we have multiple
* modes at the same time. (Physical map is always right.)
*/
static inline bool kvm_apic_logical_map_valid(struct kvm_apic_map *map)
{
return !(map->mode & (map->mode - 1));
}
static inline void
apic_logical_id(struct kvm_apic_map *map, u32 dest_id, u16 *cid, u16 *lid)
{
unsigned lid_bits;
BUILD_BUG_ON(KVM_APIC_MODE_XAPIC_CLUSTER != 4);
BUILD_BUG_ON(KVM_APIC_MODE_XAPIC_FLAT != 8);
BUILD_BUG_ON(KVM_APIC_MODE_X2APIC != 16);
lid_bits = map->mode;
*cid = dest_id >> lid_bits;
*lid = dest_id & ((1 << lid_bits) - 1);
}
static void recalculate_apic_map(struct kvm *kvm)
{
struct kvm_apic_map *new, *old = NULL;
struct kvm_vcpu *vcpu;
int i;
new = kzalloc(sizeof(struct kvm_apic_map), GFP_KERNEL);
mutex_lock(&kvm->arch.apic_map_lock);
if (!new)
goto out;
kvm_for_each_vcpu(i, vcpu, kvm) {
struct kvm_lapic *apic = vcpu->arch.apic;
u16 cid, lid;
u32 ldr, aid;
if (!kvm_apic_present(vcpu))
continue;
aid = kvm_apic_id(apic);
ldr = kvm_lapic_get_reg(apic, APIC_LDR);
if (aid < ARRAY_SIZE(new->phys_map))
new->phys_map[aid] = apic;
if (apic_x2apic_mode(apic)) {
new->mode |= KVM_APIC_MODE_X2APIC;
} else if (ldr) {
ldr = GET_APIC_LOGICAL_ID(ldr);
if (kvm_lapic_get_reg(apic, APIC_DFR) == APIC_DFR_FLAT)
new->mode |= KVM_APIC_MODE_XAPIC_FLAT;
else
new->mode |= KVM_APIC_MODE_XAPIC_CLUSTER;
}
if (!kvm_apic_logical_map_valid(new))
continue;
apic_logical_id(new, ldr, &cid, &lid);
if (lid && cid < ARRAY_SIZE(new->logical_map))
new->logical_map[cid][ffs(lid) - 1] = apic;
}
out:
old = rcu_dereference_protected(kvm->arch.apic_map,
lockdep_is_held(&kvm->arch.apic_map_lock));
rcu_assign_pointer(kvm->arch.apic_map, new);
mutex_unlock(&kvm->arch.apic_map_lock);
if (old)
kfree_rcu(old, rcu);
kvm_make_scan_ioapic_request(kvm);
}
static inline void apic_set_spiv(struct kvm_lapic *apic, u32 val)
{
bool enabled = val & APIC_SPIV_APIC_ENABLED;
kvm_lapic_set_reg(apic, APIC_SPIV, val);
if (enabled != apic->sw_enabled) {
apic->sw_enabled = enabled;
if (enabled) {
static_key_slow_dec_deferred(&apic_sw_disabled);
recalculate_apic_map(apic->vcpu->kvm);
} else
static_key_slow_inc(&apic_sw_disabled.key);
}
}
static inline void kvm_apic_set_id(struct kvm_lapic *apic, u8 id)
{
kvm_lapic_set_reg(apic, APIC_ID, id << 24);
recalculate_apic_map(apic->vcpu->kvm);
}
static inline void kvm_apic_set_ldr(struct kvm_lapic *apic, u32 id)
{
kvm_lapic_set_reg(apic, APIC_LDR, id);
recalculate_apic_map(apic->vcpu->kvm);
}
static inline void kvm_apic_set_x2apic_id(struct kvm_lapic *apic, u8 id)
{
u32 ldr = ((id >> 4) << 16) | (1 << (id & 0xf));
kvm_lapic_set_reg(apic, APIC_ID, id << 24);
kvm_lapic_set_reg(apic, APIC_LDR, ldr);
recalculate_apic_map(apic->vcpu->kvm);
}
static inline int apic_lvt_enabled(struct kvm_lapic *apic, int lvt_type)
{
return !(kvm_lapic_get_reg(apic, lvt_type) & APIC_LVT_MASKED);
}
static inline int apic_lvt_vector(struct kvm_lapic *apic, int lvt_type)
{
return kvm_lapic_get_reg(apic, lvt_type) & APIC_VECTOR_MASK;
}
static inline int apic_lvtt_oneshot(struct kvm_lapic *apic)
{
return apic->lapic_timer.timer_mode == APIC_LVT_TIMER_ONESHOT;
}
static inline int apic_lvtt_period(struct kvm_lapic *apic)
{
return apic->lapic_timer.timer_mode == APIC_LVT_TIMER_PERIODIC;
}
static inline int apic_lvtt_tscdeadline(struct kvm_lapic *apic)
{
return apic->lapic_timer.timer_mode == APIC_LVT_TIMER_TSCDEADLINE;
}
static inline int apic_lvt_nmi_mode(u32 lvt_val)
{
return (lvt_val & (APIC_MODE_MASK | APIC_LVT_MASKED)) == APIC_DM_NMI;
}
void kvm_apic_set_version(struct kvm_vcpu *vcpu)
{
struct kvm_lapic *apic = vcpu->arch.apic;
struct kvm_cpuid_entry2 *feat;
u32 v = APIC_VERSION;
if (!lapic_in_kernel(vcpu))
return;
feat = kvm_find_cpuid_entry(apic->vcpu, 0x1, 0);
if (feat && (feat->ecx & (1 << (X86_FEATURE_X2APIC & 31))))
v |= APIC_LVR_DIRECTED_EOI;
kvm_lapic_set_reg(apic, APIC_LVR, v);
}
static const unsigned int apic_lvt_mask[KVM_APIC_LVT_NUM] = {
LVT_MASK , /* part LVTT mask, timer mode mask added at runtime */
LVT_MASK | APIC_MODE_MASK, /* LVTTHMR */
LVT_MASK | APIC_MODE_MASK, /* LVTPC */
LINT_MASK, LINT_MASK, /* LVT0-1 */
LVT_MASK /* LVTERR */
};
static int find_highest_vector(void *bitmap)
{
int vec;
u32 *reg;
for (vec = MAX_APIC_VECTOR - APIC_VECTORS_PER_REG;
vec >= 0; vec -= APIC_VECTORS_PER_REG) {
reg = bitmap + REG_POS(vec);
if (*reg)
return fls(*reg) - 1 + vec;
}
return -1;
}
static u8 count_vectors(void *bitmap)
{
int vec;
u32 *reg;
u8 count = 0;
for (vec = 0; vec < MAX_APIC_VECTOR; vec += APIC_VECTORS_PER_REG) {
reg = bitmap + REG_POS(vec);
count += hweight32(*reg);
}
return count;
}
void __kvm_apic_update_irr(u32 *pir, void *regs)
{
u32 i, pir_val;
for (i = 0; i <= 7; i++) {
pir_val = xchg(&pir[i], 0);
if (pir_val)
*((u32 *)(regs + APIC_IRR + i * 0x10)) |= pir_val;
}
}
EXPORT_SYMBOL_GPL(__kvm_apic_update_irr);
void kvm_apic_update_irr(struct kvm_vcpu *vcpu, u32 *pir)
{
struct kvm_lapic *apic = vcpu->arch.apic;
__kvm_apic_update_irr(pir, apic->regs);
kvm_make_request(KVM_REQ_EVENT, vcpu);
}
EXPORT_SYMBOL_GPL(kvm_apic_update_irr);
static inline int apic_search_irr(struct kvm_lapic *apic)
{
return find_highest_vector(apic->regs + APIC_IRR);
}
static inline int apic_find_highest_irr(struct kvm_lapic *apic)
{
int result;
/*
* Note that irr_pending is just a hint. It will be always
* true with virtual interrupt delivery enabled.
*/
if (!apic->irr_pending)
return -1;
if (apic->vcpu->arch.apicv_active)
kvm_x86_ops->sync_pir_to_irr(apic->vcpu);
result = apic_search_irr(apic);
ASSERT(result == -1 || result >= 16);
return result;
}
static inline void apic_clear_irr(int vec, struct kvm_lapic *apic)
{
struct kvm_vcpu *vcpu;
vcpu = apic->vcpu;
if (unlikely(vcpu->arch.apicv_active)) {
/* try to update RVI */
apic_clear_vector(vec, apic->regs + APIC_IRR);
kvm_make_request(KVM_REQ_EVENT, vcpu);
} else {
apic->irr_pending = false;
apic_clear_vector(vec, apic->regs + APIC_IRR);
if (apic_search_irr(apic) != -1)
apic->irr_pending = true;
}
}
static inline void apic_set_isr(int vec, struct kvm_lapic *apic)
{
struct kvm_vcpu *vcpu;
if (__apic_test_and_set_vector(vec, apic->regs + APIC_ISR))
return;
vcpu = apic->vcpu;
/*
* With APIC virtualization enabled, all caching is disabled
* because the processor can modify ISR under the hood. Instead
* just set SVI.
*/
if (unlikely(vcpu->arch.apicv_active))
kvm_x86_ops->hwapic_isr_update(vcpu, vec);
else {
++apic->isr_count;
BUG_ON(apic->isr_count > MAX_APIC_VECTOR);
/*
* ISR (in service register) bit is set when injecting an interrupt.
* The highest vector is injected. Thus the latest bit set matches
* the highest bit in ISR.
*/
apic->highest_isr_cache = vec;
}
}
static inline int apic_find_highest_isr(struct kvm_lapic *apic)
{
int result;
/*
* Note that isr_count is always 1, and highest_isr_cache
* is always -1, with APIC virtualization enabled.
*/
if (!apic->isr_count)
return -1;
if (likely(apic->highest_isr_cache != -1))
return apic->highest_isr_cache;
result = find_highest_vector(apic->regs + APIC_ISR);
ASSERT(result == -1 || result >= 16);
return result;
}
static inline void apic_clear_isr(int vec, struct kvm_lapic *apic)
{
struct kvm_vcpu *vcpu;
if (!__apic_test_and_clear_vector(vec, apic->regs + APIC_ISR))
return;
vcpu = apic->vcpu;
/*
* We do get here for APIC virtualization enabled if the guest
* uses the Hyper-V APIC enlightenment. In this case we may need
* to trigger a new interrupt delivery by writing the SVI field;
* on the other hand isr_count and highest_isr_cache are unused
* and must be left alone.
*/
if (unlikely(vcpu->arch.apicv_active))
kvm_x86_ops->hwapic_isr_update(vcpu,
apic_find_highest_isr(apic));
else {
--apic->isr_count;
BUG_ON(apic->isr_count < 0);
apic->highest_isr_cache = -1;
}
}
int kvm_lapic_find_highest_irr(struct kvm_vcpu *vcpu)
{
/* This may race with setting of irr in __apic_accept_irq() and
* value returned may be wrong, but kvm_vcpu_kick() in __apic_accept_irq
* will cause vmexit immediately and the value will be recalculated
* on the next vmentry.
*/
return apic_find_highest_irr(vcpu->arch.apic);
}
static int __apic_accept_irq(struct kvm_lapic *apic, int delivery_mode,
int vector, int level, int trig_mode,
struct dest_map *dest_map);
int kvm_apic_set_irq(struct kvm_vcpu *vcpu, struct kvm_lapic_irq *irq,
struct dest_map *dest_map)
{
struct kvm_lapic *apic = vcpu->arch.apic;
return __apic_accept_irq(apic, irq->delivery_mode, irq->vector,
irq->level, irq->trig_mode, dest_map);
}
static int pv_eoi_put_user(struct kvm_vcpu *vcpu, u8 val)
{
return kvm_write_guest_cached(vcpu->kvm, &vcpu->arch.pv_eoi.data, &val,
sizeof(val));
}
static int pv_eoi_get_user(struct kvm_vcpu *vcpu, u8 *val)
{
return kvm_read_guest_cached(vcpu->kvm, &vcpu->arch.pv_eoi.data, val,
sizeof(*val));
}
static inline bool pv_eoi_enabled(struct kvm_vcpu *vcpu)
{
return vcpu->arch.pv_eoi.msr_val & KVM_MSR_ENABLED;
}
static bool pv_eoi_get_pending(struct kvm_vcpu *vcpu)
{
u8 val;
if (pv_eoi_get_user(vcpu, &val) < 0)
apic_debug("Can't read EOI MSR value: 0x%llx\n",
(unsigned long long)vcpu->arch.pv_eoi.msr_val);
return val & 0x1;
}
static void pv_eoi_set_pending(struct kvm_vcpu *vcpu)
{
if (pv_eoi_put_user(vcpu, KVM_PV_EOI_ENABLED) < 0) {
apic_debug("Can't set EOI MSR value: 0x%llx\n",
(unsigned long long)vcpu->arch.pv_eoi.msr_val);
return;
}
__set_bit(KVM_APIC_PV_EOI_PENDING, &vcpu->arch.apic_attention);
}
static void pv_eoi_clr_pending(struct kvm_vcpu *vcpu)
{
if (pv_eoi_put_user(vcpu, KVM_PV_EOI_DISABLED) < 0) {
apic_debug("Can't clear EOI MSR value: 0x%llx\n",
(unsigned long long)vcpu->arch.pv_eoi.msr_val);
return;
}
__clear_bit(KVM_APIC_PV_EOI_PENDING, &vcpu->arch.apic_attention);
}
static void apic_update_ppr(struct kvm_lapic *apic)
{
u32 tpr, isrv, ppr, old_ppr;
int isr;
old_ppr = kvm_lapic_get_reg(apic, APIC_PROCPRI);
tpr = kvm_lapic_get_reg(apic, APIC_TASKPRI);
isr = apic_find_highest_isr(apic);
isrv = (isr != -1) ? isr : 0;
if ((tpr & 0xf0) >= (isrv & 0xf0))
ppr = tpr & 0xff;
else
ppr = isrv & 0xf0;
apic_debug("vlapic %p, ppr 0x%x, isr 0x%x, isrv 0x%x",
apic, ppr, isr, isrv);
if (old_ppr != ppr) {
kvm_lapic_set_reg(apic, APIC_PROCPRI, ppr);
if (ppr < old_ppr)
kvm_make_request(KVM_REQ_EVENT, apic->vcpu);
}
}
static void apic_set_tpr(struct kvm_lapic *apic, u32 tpr)
{
kvm_lapic_set_reg(apic, APIC_TASKPRI, tpr);
apic_update_ppr(apic);
}
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;
}
static bool kvm_apic_match_physical_addr(struct kvm_lapic *apic, u32 mda)
{
if (kvm_apic_broadcast(apic, mda))
return true;
if (apic_x2apic_mode(apic))
return mda == kvm_apic_id(apic);
return mda == SET_APIC_DEST_FIELD(kvm_apic_id(apic));
}
static bool kvm_apic_match_logical_addr(struct kvm_lapic *apic, u32 mda)
{
u32 logical_id;
if (kvm_apic_broadcast(apic, mda))
return true;
logical_id = kvm_lapic_get_reg(apic, APIC_LDR);
if (apic_x2apic_mode(apic))
return ((logical_id >> 16) == (mda >> 16))
&& (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:
return (logical_id & mda) != 0;
case APIC_DFR_CLUSTER:
return ((logical_id >> 4) == (mda >> 4))
&& (logical_id & mda & 0xf) != 0;
default:
apic_debug("Bad DFR vcpu %d: %08x\n",
apic->vcpu->vcpu_id, kvm_lapic_get_reg(apic, APIC_DFR));
return false;
}
}
/* KVM APIC implementation has two quirks
* - dest always begins at 0 while xAPIC MDA has offset 24,
* - IOxAPIC messages have to be delivered (directly) to x2APIC.
*/
static u32 kvm_apic_mda(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 (!ipi && dest_id == APIC_BROADCAST && x2apic_mda)
return X2APIC_BROADCAST;
return x2apic_mda ? dest_id : SET_APIC_DEST_FIELD(dest_id);
}
bool kvm_apic_match_dest(struct kvm_vcpu *vcpu, struct kvm_lapic *source,
int short_hand, unsigned int dest, int dest_mode)
{
struct kvm_lapic *target = vcpu->arch.apic;
u32 mda = kvm_apic_mda(dest, source, target);
apic_debug("target %p, source %p, dest 0x%x, "
"dest_mode 0x%x, short_hand 0x%x\n",
target, source, dest, dest_mode, short_hand);
ASSERT(target);
switch (short_hand) {
case APIC_DEST_NOSHORT:
if (dest_mode == APIC_DEST_PHYSICAL)
return kvm_apic_match_physical_addr(target, mda);
else
return kvm_apic_match_logical_addr(target, mda);
case APIC_DEST_SELF:
return target == source;
case APIC_DEST_ALLINC:
return true;
case APIC_DEST_ALLBUT:
return target != source;
default:
apic_debug("kvm: apic: Bad dest shorthand value %x\n",
short_hand);
return false;
}
}
EXPORT_SYMBOL_GPL(kvm_apic_match_dest);
int kvm_vector_to_index(u32 vector, u32 dest_vcpus,
const unsigned long *bitmap, u32 bitmap_size)
{
u32 mod;
int i, idx = -1;
mod = vector % dest_vcpus;
for (i = 0; i <= mod; i++) {
idx = find_next_bit(bitmap, bitmap_size, idx + 1);
BUG_ON(idx == bitmap_size);
}
return idx;
}
static void kvm_apic_disabled_lapic_found(struct kvm *kvm)
{
if (!kvm->arch.disabled_lapic_found) {
kvm->arch.disabled_lapic_found = true;
printk(KERN_INFO
"Disabled LAPIC found during irq injection\n");
}
}
bool kvm_irq_delivery_to_apic_fast(struct kvm *kvm, struct kvm_lapic *src,
struct kvm_lapic_irq *irq, int *r, struct dest_map *dest_map)
{
struct kvm_apic_map *map;
unsigned long bitmap = 1;
struct kvm_lapic **dst;
int i;
bool ret, x2apic_ipi;
*r = -1;
if (irq->shorthand == APIC_DEST_SELF) {
*r = kvm_apic_set_irq(src->vcpu, irq, dest_map);
return true;
}
if (irq->shorthand)
return false;
x2apic_ipi = src && apic_x2apic_mode(src);
if (irq->dest_id == (x2apic_ipi ? X2APIC_BROADCAST : APIC_BROADCAST))
return false;
ret = true;
rcu_read_lock();
map = rcu_dereference(kvm->arch.apic_map);
if (!map) {
ret = false;
goto out;
}
if (irq->dest_mode == APIC_DEST_PHYSICAL) {
if (irq->dest_id >= ARRAY_SIZE(map->phys_map))
goto out;
dst = &map->phys_map[irq->dest_id];
} else {
u16 cid;
if (!kvm_apic_logical_map_valid(map)) {
ret = false;
goto out;
}
apic_logical_id(map, irq->dest_id, &cid, (u16 *)&bitmap);
if (cid >= ARRAY_SIZE(map->logical_map))
goto out;
dst = map->logical_map[cid];
if (!kvm_lowest_prio_delivery(irq))
goto set_irq;
if (!kvm_vector_hashing_enabled()) {
int l = -1;
for_each_set_bit(i, &bitmap, 16) {
if (!dst[i])
continue;
if (l < 0)
l = i;
else if (kvm_apic_compare_prio(dst[i]->vcpu,
dst[l]->vcpu) < 0)
l = i;
}
bitmap = (l >= 0) ? 1 << l : 0;
} else {
int idx;
unsigned int dest_vcpus;
dest_vcpus = hweight16(bitmap);
if (dest_vcpus == 0)
goto out;
idx = kvm_vector_to_index(irq->vector,
dest_vcpus, &bitmap, 16);
if (!dst[idx]) {
kvm_apic_disabled_lapic_found(kvm);
goto out;
}
bitmap = (idx >= 0) ? 1 << idx : 0;
}
}
set_irq:
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);
}
out:
rcu_read_unlock();
return ret;
}
/*
* This routine tries to handler interrupts in posted mode, here is how
* it deals with different cases:
* - For single-destination interrupts, handle it in posted mode
* - Else if vector hashing is enabled and it is a lowest-priority
* interrupt, handle it in posted mode and use the following mechanism
* to find the destinaiton vCPU.
* 1. For lowest-priority interrupts, store all the possible
* destination vCPUs in an array.
* 2. Use "guest vector % max number of destination vCPUs" to find
* the right destination vCPU in the array for the lowest-priority
* interrupt.
* - Otherwise, use remapped mode to inject the interrupt.
*/
bool kvm_intr_is_single_vcpu_fast(struct kvm *kvm, struct kvm_lapic_irq *irq,
struct kvm_vcpu **dest_vcpu)
{
struct kvm_apic_map *map;
bool ret = false;
struct kvm_lapic *dst = NULL;
if (irq->shorthand)
return false;
rcu_read_lock();
map = rcu_dereference(kvm->arch.apic_map);
if (!map)
goto out;
if (irq->dest_mode == APIC_DEST_PHYSICAL) {
if (irq->dest_id == 0xFF)
goto out;
if (irq->dest_id >= ARRAY_SIZE(map->phys_map))
goto out;
dst = map->phys_map[irq->dest_id];
if (dst && kvm_apic_present(dst->vcpu))
*dest_vcpu = dst->vcpu;
else
goto out;
} else {
u16 cid;
unsigned long bitmap = 1;
int i, r = 0;
if (!kvm_apic_logical_map_valid(map))
goto out;
apic_logical_id(map, irq->dest_id, &cid, (u16 *)&bitmap);
if (cid >= ARRAY_SIZE(map->logical_map))
goto out;
if (kvm_vector_hashing_enabled() &&
kvm_lowest_prio_delivery(irq)) {
int idx;
unsigned int dest_vcpus;
dest_vcpus = hweight16(bitmap);
if (dest_vcpus == 0)
goto out;
idx = kvm_vector_to_index(irq->vector, dest_vcpus,
&bitmap, 16);
dst = map->logical_map[cid][idx];
if (!dst) {
kvm_apic_disabled_lapic_found(kvm);
goto out;
}
*dest_vcpu = dst->vcpu;
} else {
for_each_set_bit(i, &bitmap, 16) {
dst = map->logical_map[cid][i];
if (++r == 2)
goto out;
}
if (dst && kvm_apic_present(dst->vcpu))
*dest_vcpu = dst->vcpu;
else
goto out;
}
}
ret = true;
out:
rcu_read_unlock();
return ret;
}
/*
* Add a pending IRQ into lapic.
* Return 1 if successfully added and 0 if discarded.
*/
static int __apic_accept_irq(struct kvm_lapic *apic, int delivery_mode,
int vector, int level, int trig_mode,
struct dest_map *dest_map)
{
int result = 0;
struct kvm_vcpu *vcpu = apic->vcpu;
trace_kvm_apic_accept_irq(vcpu->vcpu_id, delivery_mode,
trig_mode, vector);
switch (delivery_mode) {
case APIC_DM_LOWEST:
vcpu->arch.apic_arb_prio++;
case APIC_DM_FIXED:
if (unlikely(trig_mode && !level))
break;
/* FIXME add logic for vcpu on reset */
if (unlikely(!apic_enabled(apic)))
break;
result = 1;
if (dest_map) {
__set_bit(vcpu->vcpu_id, dest_map->map);
dest_map->vectors[vcpu->vcpu_id] = vector;
}
if (apic_test_vector(vector, apic->regs + APIC_TMR) != !!trig_mode) {
if (trig_mode)
kvm_lapic_set_vector(vector, apic->regs + APIC_TMR);
else
apic_clear_vector(vector, apic->regs + APIC_TMR);
}
if (vcpu->arch.apicv_active)
kvm_x86_ops->deliver_posted_interrupt(vcpu, vector);
else {
kvm_lapic_set_irr(vector, apic);
kvm_make_request(KVM_REQ_EVENT, vcpu);
kvm_vcpu_kick(vcpu);
}
break;
case APIC_DM_REMRD:
result = 1;
vcpu->arch.pv.pv_unhalted = 1;
kvm_make_request(KVM_REQ_EVENT, vcpu);
kvm_vcpu_kick(vcpu);
break;
case APIC_DM_SMI:
result = 1;
kvm_make_request(KVM_REQ_SMI, vcpu);
kvm_vcpu_kick(vcpu);
break;
case APIC_DM_NMI:
result = 1;
kvm_inject_nmi(vcpu);
kvm_vcpu_kick(vcpu);
break;
case APIC_DM_INIT:
if (!trig_mode || level) {
result = 1;
/* assumes that there are only KVM_APIC_INIT/SIPI */
apic->pending_events = (1UL << KVM_APIC_INIT);
/* make sure pending_events is visible before sending
* the request */
smp_wmb();
kvm_make_request(KVM_REQ_EVENT, vcpu);
kvm_vcpu_kick(vcpu);
} else {
apic_debug("Ignoring de-assert INIT to vcpu %d\n",
vcpu->vcpu_id);
}
break;
case APIC_DM_STARTUP:
apic_debug("SIPI to vcpu %d vector 0x%02x\n",
vcpu->vcpu_id, vector);
result = 1;
apic->sipi_vector = vector;
/* make sure sipi_vector is visible for the receiver */
smp_wmb();
set_bit(KVM_APIC_SIPI, &apic->pending_events);
kvm_make_request(KVM_REQ_EVENT, vcpu);
kvm_vcpu_kick(vcpu);
break;
case APIC_DM_EXTINT:
/*
* Should only be called by kvm_apic_local_deliver() with LVT0,
* before NMI watchdog was enabled. Already handled by
* kvm_apic_accept_pic_intr().
*/
break;
default:
printk(KERN_ERR "TODO: unsupported delivery mode %x\n",
delivery_mode);
break;
}
return result;
}
int kvm_apic_compare_prio(struct kvm_vcpu *vcpu1, struct kvm_vcpu *vcpu2)
{
return vcpu1->arch.apic_arb_prio - vcpu2->arch.apic_arb_prio;
}
static bool kvm_ioapic_handles_vector(struct kvm_lapic *apic, int vector)
{
return test_bit(vector, apic->vcpu->arch.ioapic_handled_vectors);
}
static void kvm_ioapic_send_eoi(struct kvm_lapic *apic, int vector)
{
int trigger_mode;
/* Eoi the ioapic only if the ioapic doesn't own the vector. */
if (!kvm_ioapic_handles_vector(apic, vector))
return;
/* Request a KVM exit to inform the userspace IOAPIC. */
if (irqchip_split(apic->vcpu->kvm)) {
apic->vcpu->arch.pending_ioapic_eoi = vector;
kvm_make_request(KVM_REQ_IOAPIC_EOI_EXIT, apic->vcpu);
return;
}
if (apic_test_vector(vector, apic->regs + APIC_TMR))
trigger_mode = IOAPIC_LEVEL_TRIG;
else
trigger_mode = IOAPIC_EDGE_TRIG;
kvm_ioapic_update_eoi(apic->vcpu, vector, trigger_mode);
}
static int apic_set_eoi(struct kvm_lapic *apic)
{
int vector = apic_find_highest_isr(apic);
trace_kvm_eoi(apic, vector);
/*
* Not every write EOI will has corresponding ISR,
* one example is when Kernel check timer on setup_IO_APIC
*/
if (vector == -1)
return vector;
apic_clear_isr(vector, apic);
apic_update_ppr(apic);
if (test_bit(vector, vcpu_to_synic(apic->vcpu)->vec_bitmap))
kvm_hv_synic_send_eoi(apic->vcpu, vector);
kvm_ioapic_send_eoi(apic, vector);
kvm_make_request(KVM_REQ_EVENT, apic->vcpu);
return vector;
}
/*
* this interface assumes a trap-like exit, which has already finished
* desired side effect including vISR and vPPR update.
*/
void kvm_apic_set_eoi_accelerated(struct kvm_vcpu *vcpu, int vector)
{
struct kvm_lapic *apic = vcpu->arch.apic;
trace_kvm_eoi(apic, vector);
kvm_ioapic_send_eoi(apic, vector);
kvm_make_request(KVM_REQ_EVENT, apic->vcpu);
}
EXPORT_SYMBOL_GPL(kvm_apic_set_eoi_accelerated);
static void apic_send_ipi(struct kvm_lapic *apic)
{
u32 icr_low = kvm_lapic_get_reg(apic, APIC_ICR);
u32 icr_high = kvm_lapic_get_reg(apic, APIC_ICR2);
struct kvm_lapic_irq irq;
irq.vector = icr_low & APIC_VECTOR_MASK;
irq.delivery_mode = icr_low & APIC_MODE_MASK;
irq.dest_mode = icr_low & APIC_DEST_MASK;
irq.level = (icr_low & APIC_INT_ASSERT) != 0;
irq.trig_mode = icr_low & APIC_INT_LEVELTRIG;
irq.shorthand = icr_low & APIC_SHORT_MASK;
irq.msi_redir_hint = false;
if (apic_x2apic_mode(apic))
irq.dest_id = icr_high;
else
irq.dest_id = GET_APIC_DEST_FIELD(icr_high);
trace_kvm_apic_ipi(icr_low, irq.dest_id);
apic_debug("icr_high 0x%x, icr_low 0x%x, "
"short_hand 0x%x, dest 0x%x, trig_mode 0x%x, level 0x%x, "
"dest_mode 0x%x, delivery_mode 0x%x, vector 0x%x, "
"msi_redir_hint 0x%x\n",
icr_high, icr_low, irq.shorthand, irq.dest_id,
irq.trig_mode, irq.level, irq.dest_mode, irq.delivery_mode,
irq.vector, irq.msi_redir_hint);
kvm_irq_delivery_to_apic(apic->vcpu->kvm, apic, &irq, NULL);
}
static u32 apic_get_tmcct(struct kvm_lapic *apic)
{
ktime_t remaining;
s64 ns;
u32 tmcct;
ASSERT(apic != NULL);
/* if initial count is 0, current count should also be 0 */
if (kvm_lapic_get_reg(apic, APIC_TMICT) == 0 ||
apic->lapic_timer.period == 0)
return 0;
remaining = hrtimer_get_remaining(&apic->lapic_timer.timer);
if (ktime_to_ns(remaining) < 0)
remaining = ktime_set(0, 0);
ns = mod_64(ktime_to_ns(remaining), apic->lapic_timer.period);
tmcct = div64_u64(ns,
(APIC_BUS_CYCLE_NS * apic->divide_count));
return tmcct;
}
static void __report_tpr_access(struct kvm_lapic *apic, bool write)
{
struct kvm_vcpu *vcpu = apic->vcpu;
struct kvm_run *run = vcpu->run;
kvm_make_request(KVM_REQ_REPORT_TPR_ACCESS, vcpu);
run->tpr_access.rip = kvm_rip_read(vcpu);
run->tpr_access.is_write = write;
}
static inline void report_tpr_access(struct kvm_lapic *apic, bool write)
{
if (apic->vcpu->arch.tpr_access_reporting)
__report_tpr_access(apic, write);
}
static u32 __apic_read(struct kvm_lapic *apic, unsigned int offset)
{
u32 val = 0;
if (offset >= LAPIC_MMIO_LENGTH)
return 0;
switch (offset) {
case APIC_ID:
if (apic_x2apic_mode(apic))
val = kvm_apic_id(apic);
else
val = kvm_apic_id(apic) << 24;
break;
case APIC_ARBPRI:
apic_debug("Access APIC ARBPRI register which is for P6\n");
break;
case APIC_TMCCT: /* Timer CCR */
if (apic_lvtt_tscdeadline(apic))
return 0;
val = apic_get_tmcct(apic);
break;
case APIC_PROCPRI:
apic_update_ppr(apic);
val = kvm_lapic_get_reg(apic, offset);
break;
case APIC_TASKPRI:
report_tpr_access(apic, false);
/* fall thru */
default:
val = kvm_lapic_get_reg(apic, offset);
break;
}
return val;
}
static inline struct kvm_lapic *to_lapic(struct kvm_io_device *dev)
{
return container_of(dev, struct kvm_lapic, dev);
}
int kvm_lapic_reg_read(struct kvm_lapic *apic, u32 offset, int len,
void *data)
{
unsigned char alignment = offset & 0xf;
u32 result;
/* this bitmask has a bit cleared for each reserved register */
static const u64 rmask = 0x43ff01ffffffe70cULL;
if ((alignment + len) > 4) {
apic_debug("KVM_APIC_READ: alignment error %x %d\n",
offset, len);
return 1;
}
if (offset > 0x3f0 || !(rmask & (1ULL << (offset >> 4)))) {
apic_debug("KVM_APIC_READ: read reserved register %x\n",
offset);
return 1;
}
result = __apic_read(apic, offset & ~0xf);
trace_kvm_apic_read(offset, result);
switch (len) {
case 1:
case 2:
case 4:
memcpy(data, (char *)&result + alignment, len);
break;
default:
printk(KERN_ERR "Local APIC read with len = %x, "
"should be 1,2, or 4 instead\n", len);
break;
}
return 0;
}
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;
}
static int apic_mmio_read(struct kvm_vcpu *vcpu, struct kvm_io_device *this,
gpa_t address, int len, void *data)
{
struct kvm_lapic *apic = to_lapic(this);
u32 offset = address - apic->base_address;
if (!apic_mmio_in_range(apic, address))
return -EOPNOTSUPP;
kvm_lapic_reg_read(apic, offset, len, data);
return 0;
}
static void update_divide_count(struct kvm_lapic *apic)
{
u32 tmp1, tmp2, tdcr;
tdcr = kvm_lapic_get_reg(apic, APIC_TDCR);
tmp1 = tdcr & 0xf;
tmp2 = ((tmp1 & 0x3) | ((tmp1 & 0x8) >> 1)) + 1;
apic->divide_count = 0x1 << (tmp2 & 0x7);
apic_debug("timer divide count is 0x%x\n",
apic->divide_count);
}
static void apic_update_lvtt(struct kvm_lapic *apic)
{
u32 timer_mode = kvm_lapic_get_reg(apic, APIC_LVTT) &
apic->lapic_timer.timer_mode_mask;
if (apic->lapic_timer.timer_mode != timer_mode) {
apic->lapic_timer.timer_mode = timer_mode;
hrtimer_cancel(&apic->lapic_timer.timer);
}
}
static void apic_timer_expired(struct kvm_lapic *apic)
{
struct kvm_vcpu *vcpu = apic->vcpu;
struct swait_queue_head *q = &vcpu->wq;
struct kvm_timer *ktimer = &apic->lapic_timer;
if (atomic_read(&apic->lapic_timer.pending))
return;
atomic_inc(&apic->lapic_timer.pending);
kvm_set_pending_timer(vcpu);
if (swait_active(q))
swake_up(q);
if (apic_lvtt_tscdeadline(apic))
ktimer->expired_tscdeadline = ktimer->tscdeadline;
}
/*
* On APICv, this test will cause a busy wait
* during a higher-priority task.
*/
static bool lapic_timer_int_injected(struct kvm_vcpu *vcpu)
{
struct kvm_lapic *apic = vcpu->arch.apic;
u32 reg = kvm_lapic_get_reg(apic, APIC_LVTT);
if (kvm_apic_hw_enabled(apic)) {
int vec = reg & APIC_VECTOR_MASK;
void *bitmap = apic->regs + APIC_ISR;
if (vcpu->arch.apicv_active)
bitmap = apic->regs + APIC_IRR;
if (apic_test_vector(vec, bitmap))
return true;
}
return false;
}
void wait_lapic_expire(struct kvm_vcpu *vcpu)
{
struct kvm_lapic *apic = vcpu->arch.apic;
u64 guest_tsc, tsc_deadline;
if (!lapic_in_kernel(vcpu))
return;
if (apic->lapic_timer.expired_tscdeadline == 0)
return;
if (!lapic_timer_int_injected(vcpu))
return;
tsc_deadline = apic->lapic_timer.expired_tscdeadline;
apic->lapic_timer.expired_tscdeadline = 0;
guest_tsc = kvm_read_l1_tsc(vcpu, rdtsc());
trace_kvm_wait_lapic_expire(vcpu->vcpu_id, guest_tsc - tsc_deadline);
/* __delay is delay_tsc whenever the hardware has TSC, thus always. */
if (guest_tsc < tsc_deadline)
__delay(min(tsc_deadline - guest_tsc,
nsec_to_cycles(vcpu, lapic_timer_advance_ns)));
}
static void start_apic_timer(struct kvm_lapic *apic)
{
ktime_t now;
atomic_set(&apic->lapic_timer.pending, 0);
if (apic_lvtt_period(apic) || apic_lvtt_oneshot(apic)) {
/* lapic timer in oneshot or periodic mode */
now = apic->lapic_timer.timer.base->get_time();
apic->lapic_timer.period = (u64)kvm_lapic_get_reg(apic, APIC_TMICT)
* APIC_BUS_CYCLE_NS * apic->divide_count;
if (!apic->lapic_timer.period)
return;
/*
* Do not allow the guest to program periodic timers with small
* interval, since the hrtimers are not throttled by the host
* scheduler.
*/
if (apic_lvtt_period(apic)) {
s64 min_period = min_timer_period_us * 1000LL;
if (apic->lapic_timer.period < min_period) {
pr_info_ratelimited(
"kvm: vcpu %i: requested %lld ns "
"lapic timer period limited to %lld ns\n",
apic->vcpu->vcpu_id,
apic->lapic_timer.period, min_period);
apic->lapic_timer.period = min_period;
}
}
hrtimer_start(&apic->lapic_timer.timer,
ktime_add_ns(now, apic->lapic_timer.period),
HRTIMER_MODE_ABS_PINNED);
apic_debug("%s: bus cycle is %" PRId64 "ns, now 0x%016"
PRIx64 ", "
"timer initial count 0x%x, period %lldns, "
"expire @ 0x%016" PRIx64 ".\n", __func__,
APIC_BUS_CYCLE_NS, ktime_to_ns(now),
kvm_lapic_get_reg(apic, APIC_TMICT),
apic->lapic_timer.period,
ktime_to_ns(ktime_add_ns(now,
apic->lapic_timer.period)));
} else if (apic_lvtt_tscdeadline(apic)) {
/* lapic timer in tsc deadline mode */
u64 guest_tsc, tscdeadline = apic->lapic_timer.tscdeadline;
u64 ns = 0;
ktime_t expire;
struct kvm_vcpu *vcpu = apic->vcpu;
unsigned long this_tsc_khz = vcpu->arch.virtual_tsc_khz;
unsigned long flags;
if (unlikely(!tscdeadline || !this_tsc_khz))
return;
local_irq_save(flags);
now = apic->lapic_timer.timer.base->get_time();
guest_tsc = kvm_read_l1_tsc(vcpu, rdtsc());
if (likely(tscdeadline > guest_tsc)) {
ns = (tscdeadline - guest_tsc) * 1000000ULL;
do_div(ns, this_tsc_khz);
expire = ktime_add_ns(now, ns);
expire = ktime_sub_ns(expire, lapic_timer_advance_ns);
hrtimer_start(&apic->lapic_timer.timer,
expire, HRTIMER_MODE_ABS_PINNED);
} else
apic_timer_expired(apic);
local_irq_restore(flags);
}
}
static void apic_manage_nmi_watchdog(struct kvm_lapic *apic, u32 lvt0_val)
{
bool lvt0_in_nmi_mode = apic_lvt_nmi_mode(lvt0_val);
if (apic->lvt0_in_nmi_mode != lvt0_in_nmi_mode) {
apic->lvt0_in_nmi_mode = lvt0_in_nmi_mode;
if (lvt0_in_nmi_mode) {
apic_debug("Receive NMI setting on APIC_LVT0 "
"for cpu %d\n", apic->vcpu->vcpu_id);
atomic_inc(&apic->vcpu->kvm->arch.vapics_in_nmi_mode);
} else
atomic_dec(&apic->vcpu->kvm->arch.vapics_in_nmi_mode);
}
}
int kvm_lapic_reg_write(struct kvm_lapic *apic, u32 reg, u32 val)
{
int ret = 0;
trace_kvm_apic_write(reg, val);
switch (reg) {
case APIC_ID: /* Local APIC ID */
if (!apic_x2apic_mode(apic))
kvm_apic_set_id(apic, val >> 24);
else
ret = 1;
break;
case APIC_TASKPRI:
report_tpr_access(apic, true);
apic_set_tpr(apic, val & 0xff);
break;
case APIC_EOI:
apic_set_eoi(apic);
break;
case APIC_LDR:
if (!apic_x2apic_mode(apic))
kvm_apic_set_ldr(apic, val & APIC_LDR_MASK);
else
ret = 1;
break;
case APIC_DFR:
if (!apic_x2apic_mode(apic)) {
kvm_lapic_set_reg(apic, APIC_DFR, val | 0x0FFFFFFF);
recalculate_apic_map(apic->vcpu->kvm);
} else
ret = 1;
break;
case APIC_SPIV: {
u32 mask = 0x3ff;
if (kvm_lapic_get_reg(apic, APIC_LVR) & APIC_LVR_DIRECTED_EOI)
mask |= APIC_SPIV_DIRECTED_EOI;
apic_set_spiv(apic, val & mask);
if (!(val & APIC_SPIV_APIC_ENABLED)) {
int i;
u32 lvt_val;
for (i = 0; i < KVM_APIC_LVT_NUM; i++) {
lvt_val = kvm_lapic_get_reg(apic,
APIC_LVTT + 0x10 * i);
kvm_lapic_set_reg(apic, APIC_LVTT + 0x10 * i,
lvt_val | APIC_LVT_MASKED);
}
apic_update_lvtt(apic);
atomic_set(&apic->lapic_timer.pending, 0);
}
break;
}
case APIC_ICR:
/* No delay here, so we always clear the pending bit */
kvm_lapic_set_reg(apic, APIC_ICR, val & ~(1 << 12));
apic_send_ipi(apic);
break;
case APIC_ICR2:
if (!apic_x2apic_mode(apic))
val &= 0xff000000;
kvm_lapic_set_reg(apic, APIC_ICR2, val);
break;
case APIC_LVT0:
apic_manage_nmi_watchdog(apic, val);
case APIC_LVTTHMR:
case APIC_LVTPC:
case APIC_LVT1:
case APIC_LVTERR:
/* TODO: Check vector */
if (!kvm_apic_sw_enabled(apic))
val |= APIC_LVT_MASKED;
val &= apic_lvt_mask[(reg - APIC_LVTT) >> 4];
kvm_lapic_set_reg(apic, reg, val);
break;
case APIC_LVTT:
if (!kvm_apic_sw_enabled(apic))
val |= APIC_LVT_MASKED;
val &= (apic_lvt_mask[0] | apic->lapic_timer.timer_mode_mask);
kvm_lapic_set_reg(apic, APIC_LVTT, val);
apic_update_lvtt(apic);
break;
case APIC_TMICT:
if (apic_lvtt_tscdeadline(apic))
break;
hrtimer_cancel(&apic->lapic_timer.timer);
kvm_lapic_set_reg(apic, APIC_TMICT, val);
start_apic_timer(apic);
break;
case APIC_TDCR:
if (val & 4)
apic_debug("KVM_WRITE:TDCR %x\n", val);
kvm_lapic_set_reg(apic, APIC_TDCR, val);
update_divide_count(apic);
break;
case APIC_ESR:
if (apic_x2apic_mode(apic) && val != 0) {
apic_debug("KVM_WRITE:ESR not zero %x\n", val);
ret = 1;
}
break;
case APIC_SELF_IPI:
if (apic_x2apic_mode(apic)) {
kvm_lapic_reg_write(apic, APIC_ICR, 0x40000 | (val & 0xff));
} else
ret = 1;
break;
default:
ret = 1;
break;
}
if (ret)
apic_debug("Local APIC Write to read-only register %x\n", reg);
return ret;
}
EXPORT_SYMBOL_GPL(kvm_lapic_reg_write);
static int apic_mmio_write(struct kvm_vcpu *vcpu, struct kvm_io_device *this,
gpa_t address, int len, const void *data)
{
struct kvm_lapic *apic = to_lapic(this);
unsigned int offset = address - apic->base_address;
u32 val;
if (!apic_mmio_in_range(apic, address))
return -EOPNOTSUPP;
/*
* APIC register must be aligned on 128-bits boundary.
* 32/64/128 bits registers must be accessed thru 32 bits.
* Refer SDM 8.4.1
*/
if (len != 4 || (offset & 0xf)) {
/* Don't shout loud, $infamous_os would cause only noise. */
apic_debug("apic write: bad size=%d %lx\n", len, (long)address);
return 0;
}
val = *(u32*)data;
/* too common printing */
if (offset != APIC_EOI)
apic_debug("%s: offset 0x%x with length 0x%x, and value is "
"0x%x\n", __func__, offset, len, val);
kvm_lapic_reg_write(apic, offset & 0xff0, val);
return 0;
}
void kvm_lapic_set_eoi(struct kvm_vcpu *vcpu)
{
kvm_lapic_reg_write(vcpu->arch.apic, APIC_EOI, 0);
}
EXPORT_SYMBOL_GPL(kvm_lapic_set_eoi);
/* emulate APIC access in a trap manner */
void kvm_apic_write_nodecode(struct kvm_vcpu *vcpu, u32 offset)
{
u32 val = 0;
/* hw has done the conditional check and inst decode */
offset &= 0xff0;
kvm_lapic_reg_read(vcpu->arch.apic, offset, 4, &val);
/* TODO: optimize to just emulate side effect w/o one more write */
kvm_lapic_reg_write(vcpu->arch.apic, offset, val);
}
EXPORT_SYMBOL_GPL(kvm_apic_write_nodecode);
void kvm_free_lapic(struct kvm_vcpu *vcpu)
{
struct kvm_lapic *apic = vcpu->arch.apic;
if (!vcpu->arch.apic)
return;
hrtimer_cancel(&apic->lapic_timer.timer);
if (!(vcpu->arch.apic_base & MSR_IA32_APICBASE_ENABLE))
static_key_slow_dec_deferred(&apic_hw_disabled);
if (!apic->sw_enabled)
static_key_slow_dec_deferred(&apic_sw_disabled);
if (apic->regs)
free_page((unsigned long)apic->regs);
kfree(apic);
}
/*
*----------------------------------------------------------------------
* LAPIC interface
*----------------------------------------------------------------------
*/
u64 kvm_get_lapic_tscdeadline_msr(struct kvm_vcpu *vcpu)
{
struct kvm_lapic *apic = vcpu->arch.apic;
if (!lapic_in_kernel(vcpu) || apic_lvtt_oneshot(apic) ||
apic_lvtt_period(apic))
return 0;
return apic->lapic_timer.tscdeadline;
}
void kvm_set_lapic_tscdeadline_msr(struct kvm_vcpu *vcpu, u64 data)
{
struct kvm_lapic *apic = vcpu->arch.apic;
if (!lapic_in_kernel(vcpu) || apic_lvtt_oneshot(apic) ||
apic_lvtt_period(apic))
return;
hrtimer_cancel(&apic->lapic_timer.timer);
apic->lapic_timer.tscdeadline = data;
start_apic_timer(apic);
}
void kvm_lapic_set_tpr(struct kvm_vcpu *vcpu, unsigned long cr8)
{
struct kvm_lapic *apic = vcpu->arch.apic;
apic_set_tpr(apic, ((cr8 & 0x0f) << 4)
| (kvm_lapic_get_reg(apic, APIC_TASKPRI) & 4));
}
u64 kvm_lapic_get_cr8(struct kvm_vcpu *vcpu)
{
u64 tpr;
tpr = (u64) kvm_lapic_get_reg(vcpu->arch.apic, APIC_TASKPRI);
return (tpr & 0xf0) >> 4;
}
void kvm_lapic_set_base(struct kvm_vcpu *vcpu, u64 value)
{
u64 old_value = vcpu->arch.apic_base;
struct kvm_lapic *apic = vcpu->arch.apic;
if (!apic) {
value |= MSR_IA32_APICBASE_BSP;
vcpu->arch.apic_base = value;
return;
}
vcpu->arch.apic_base = value;
/* update jump label if enable bit changes */
if ((old_value ^ value) & MSR_IA32_APICBASE_ENABLE) {
if (value & MSR_IA32_APICBASE_ENABLE)
static_key_slow_dec_deferred(&apic_hw_disabled);
else
static_key_slow_inc(&apic_hw_disabled.key);
recalculate_apic_map(vcpu->kvm);
}
if ((old_value ^ value) & X2APIC_ENABLE) {
if (value & X2APIC_ENABLE) {
kvm_apic_set_x2apic_id(apic, vcpu->vcpu_id);
kvm_x86_ops->set_virtual_x2apic_mode(vcpu, true);
} else
kvm_x86_ops->set_virtual_x2apic_mode(vcpu, false);
}
apic->base_address = apic->vcpu->arch.apic_base &
MSR_IA32_APICBASE_BASE;
if ((value & MSR_IA32_APICBASE_ENABLE) &&
apic->base_address != APIC_DEFAULT_PHYS_BASE)
pr_warn_once("APIC base relocation is unsupported by KVM");
/* with FSB delivery interrupt, we can restart APIC functionality */
apic_debug("apic base msr is 0x%016" PRIx64 ", and base address is "
"0x%lx.\n", apic->vcpu->arch.apic_base, apic->base_address);
}
void kvm_lapic_reset(struct kvm_vcpu *vcpu, bool init_event)
{
struct kvm_lapic *apic;
int i;
apic_debug("%s\n", __func__);
ASSERT(vcpu);
apic = vcpu->arch.apic;
ASSERT(apic != NULL);
/* Stop the timer in case it's a reset to an active apic */
hrtimer_cancel(&apic->lapic_timer.timer);
if (!init_event)
kvm_apic_set_id(apic, vcpu->vcpu_id);
kvm_apic_set_version(apic->vcpu);
for (i = 0; i < KVM_APIC_LVT_NUM; i++)
kvm_lapic_set_reg(apic, APIC_LVTT + 0x10 * i, APIC_LVT_MASKED);
apic_update_lvtt(apic);
if (kvm_check_has_quirk(vcpu->kvm, KVM_X86_QUIRK_LINT0_REENABLED))
kvm_lapic_set_reg(apic, APIC_LVT0,
SET_APIC_DELIVERY_MODE(0, APIC_MODE_EXTINT));
apic_manage_nmi_watchdog(apic, kvm_lapic_get_reg(apic, APIC_LVT0));
kvm_lapic_set_reg(apic, APIC_DFR, 0xffffffffU);
apic_set_spiv(apic, 0xff);
kvm_lapic_set_reg(apic, APIC_TASKPRI, 0);
if (!apic_x2apic_mode(apic))
kvm_apic_set_ldr(apic, 0);
kvm_lapic_set_reg(apic, APIC_ESR, 0);
kvm_lapic_set_reg(apic, APIC_ICR, 0);
kvm_lapic_set_reg(apic, APIC_ICR2, 0);
kvm_lapic_set_reg(apic, APIC_TDCR, 0);
kvm_lapic_set_reg(apic, APIC_TMICT, 0);
for (i = 0; i < 8; i++) {
kvm_lapic_set_reg(apic, APIC_IRR + 0x10 * i, 0);
kvm_lapic_set_reg(apic, APIC_ISR + 0x10 * i, 0);
kvm_lapic_set_reg(apic, APIC_TMR + 0x10 * i, 0);
}
apic->irr_pending = vcpu->arch.apicv_active;
apic->isr_count = vcpu->arch.apicv_active ? 1 : 0;
apic->highest_isr_cache = -1;
update_divide_count(apic);
atomic_set(&apic->lapic_timer.pending, 0);
if (kvm_vcpu_is_bsp(vcpu))
kvm_lapic_set_base(vcpu,
vcpu->arch.apic_base | MSR_IA32_APICBASE_BSP);
vcpu->arch.pv_eoi.msr_val = 0;
apic_update_ppr(apic);
vcpu->arch.apic_arb_prio = 0;
vcpu->arch.apic_attention = 0;
apic_debug("%s: vcpu=%p, id=%d, base_msr="
"0x%016" PRIx64 ", base_address=0x%0lx.\n", __func__,
vcpu, kvm_apic_id(apic),
vcpu->arch.apic_base, apic->base_address);
}
/*
*----------------------------------------------------------------------
* timer interface
*----------------------------------------------------------------------
*/
static bool lapic_is_periodic(struct kvm_lapic *apic)
{
return apic_lvtt_period(apic);
}
int apic_has_pending_timer(struct kvm_vcpu *vcpu)
{
struct kvm_lapic *apic = vcpu->arch.apic;
if (apic_enabled(apic) && apic_lvt_enabled(apic, APIC_LVTT))
return atomic_read(&apic->lapic_timer.pending);
return 0;
}
int kvm_apic_local_deliver(struct kvm_lapic *apic, int lvt_type)
{
u32 reg = kvm_lapic_get_reg(apic, lvt_type);
int vector, mode, trig_mode;
if (kvm_apic_hw_enabled(apic) && !(reg & APIC_LVT_MASKED)) {
vector = reg & APIC_VECTOR_MASK;
mode = reg & APIC_MODE_MASK;
trig_mode = reg & APIC_LVT_LEVEL_TRIGGER;
return __apic_accept_irq(apic, mode, vector, 1, trig_mode,
NULL);
}
return 0;
}
void kvm_apic_nmi_wd_deliver(struct kvm_vcpu *vcpu)
{
struct kvm_lapic *apic = vcpu->arch.apic;
if (apic)
kvm_apic_local_deliver(apic, APIC_LVT0);
}
static const struct kvm_io_device_ops apic_mmio_ops = {
.read = apic_mmio_read,
.write = apic_mmio_write,
};
static enum hrtimer_restart apic_timer_fn(struct hrtimer *data)
{
struct kvm_timer *ktimer = container_of(data, struct kvm_timer, timer);
struct kvm_lapic *apic = container_of(ktimer, struct kvm_lapic, lapic_timer);
apic_timer_expired(apic);
if (lapic_is_periodic(apic)) {
hrtimer_add_expires_ns(&ktimer->timer, ktimer->period);
return HRTIMER_RESTART;
} else
return HRTIMER_NORESTART;
}
int kvm_create_lapic(struct kvm_vcpu *vcpu)
{
struct kvm_lapic *apic;
ASSERT(vcpu != NULL);
apic_debug("apic_init %d\n", vcpu->vcpu_id);
apic = kzalloc(sizeof(*apic), GFP_KERNEL);
if (!apic)
goto nomem;
vcpu->arch.apic = apic;
apic->regs = (void *)get_zeroed_page(GFP_KERNEL);
if (!apic->regs) {
printk(KERN_ERR "malloc apic regs error for vcpu %x\n",
vcpu->vcpu_id);
goto nomem_free_apic;
}
apic->vcpu = vcpu;
hrtimer_init(&apic->lapic_timer.timer, CLOCK_MONOTONIC,
HRTIMER_MODE_ABS_PINNED);
apic->lapic_timer.timer.function = apic_timer_fn;
/*
* APIC is created enabled. This will prevent kvm_lapic_set_base from
* thinking that APIC satet has changed.
*/
vcpu->arch.apic_base = MSR_IA32_APICBASE_ENABLE;
kvm_lapic_set_base(vcpu,
APIC_DEFAULT_PHYS_BASE | MSR_IA32_APICBASE_ENABLE);
static_key_slow_inc(&apic_sw_disabled.key); /* sw disabled at reset */
kvm_lapic_reset(vcpu, false);
kvm_iodevice_init(&apic->dev, &apic_mmio_ops);
return 0;
nomem_free_apic:
kfree(apic);
nomem:
return -ENOMEM;
}
int kvm_apic_has_interrupt(struct kvm_vcpu *vcpu)
{
struct kvm_lapic *apic = vcpu->arch.apic;
int highest_irr;
if (!apic_enabled(apic))
return -1;
apic_update_ppr(apic);
highest_irr = apic_find_highest_irr(apic);
if ((highest_irr == -1) ||
((highest_irr & 0xF0) <= kvm_lapic_get_reg(apic, APIC_PROCPRI)))
return -1;
return highest_irr;
}
int kvm_apic_accept_pic_intr(struct kvm_vcpu *vcpu)
{
u32 lvt0 = kvm_lapic_get_reg(vcpu->arch.apic, APIC_LVT0);
int r = 0;
if (!kvm_apic_hw_enabled(vcpu->arch.apic))
r = 1;
if ((lvt0 & APIC_LVT_MASKED) == 0 &&
GET_APIC_DELIVERY_MODE(lvt0) == APIC_MODE_EXTINT)
r = 1;
return r;
}
void kvm_inject_apic_timer_irqs(struct kvm_vcpu *vcpu)
{
struct kvm_lapic *apic = vcpu->arch.apic;
if (atomic_read(&apic->lapic_timer.pending) > 0) {
kvm_apic_local_deliver(apic, APIC_LVTT);
if (apic_lvtt_tscdeadline(apic))
apic->lapic_timer.tscdeadline = 0;
atomic_set(&apic->lapic_timer.pending, 0);
}
}
int kvm_get_apic_interrupt(struct kvm_vcpu *vcpu)
{
int vector = kvm_apic_has_interrupt(vcpu);
struct kvm_lapic *apic = vcpu->arch.apic;
if (vector == -1)
return -1;
/*
* We get here even with APIC virtualization enabled, if doing
* nested virtualization and L1 runs with the "acknowledge interrupt
* on exit" mode. Then we cannot inject the interrupt via RVI,
* because the process would deliver it through the IDT.
*/
apic_set_isr(vector, apic);
apic_update_ppr(apic);
apic_clear_irr(vector, apic);
if (test_bit(vector, vcpu_to_synic(vcpu)->auto_eoi_bitmap)) {
apic_clear_isr(vector, apic);
apic_update_ppr(apic);
}
return vector;
}
void kvm_apic_post_state_restore(struct kvm_vcpu *vcpu,
struct kvm_lapic_state *s)
{
struct kvm_lapic *apic = vcpu->arch.apic;
kvm_lapic_set_base(vcpu, vcpu->arch.apic_base);
/* set SPIV separately to get count of SW disabled APICs right */
apic_set_spiv(apic, *((u32 *)(s->regs + APIC_SPIV)));
memcpy(vcpu->arch.apic->regs, s->regs, sizeof *s);
/* call kvm_apic_set_id() to put apic into apic_map */
kvm_apic_set_id(apic, kvm_apic_id(apic));
kvm_apic_set_version(vcpu);
apic_update_ppr(apic);
hrtimer_cancel(&apic->lapic_timer.timer);
apic_update_lvtt(apic);
apic_manage_nmi_watchdog(apic, kvm_lapic_get_reg(apic, APIC_LVT0));
update_divide_count(apic);
start_apic_timer(apic);
apic->irr_pending = true;
apic->isr_count = vcpu->arch.apicv_active ?
1 : count_vectors(apic->regs + APIC_ISR);
apic->highest_isr_cache = -1;
if (vcpu->arch.apicv_active) {
if (kvm_x86_ops->apicv_post_state_restore)
kvm_x86_ops->apicv_post_state_restore(vcpu);
kvm_x86_ops->hwapic_irr_update(vcpu,
apic_find_highest_irr(apic));
kvm_x86_ops->hwapic_isr_update(vcpu,
apic_find_highest_isr(apic));
}
kvm_make_request(KVM_REQ_EVENT, vcpu);
if (ioapic_in_kernel(vcpu->kvm))
kvm_rtc_eoi_tracking_restore_one(vcpu);
vcpu->arch.apic_arb_prio = 0;
}
void __kvm_migrate_apic_timer(struct kvm_vcpu *vcpu)
{
struct hrtimer *timer;
if (!lapic_in_kernel(vcpu))
return;
timer = &vcpu->arch.apic->lapic_timer.timer;
if (hrtimer_cancel(timer))
hrtimer_start_expires(timer, HRTIMER_MODE_ABS_PINNED);
}
/*
* apic_sync_pv_eoi_from_guest - called on vmexit or cancel interrupt
*
* Detect whether guest triggered PV EOI since the
* last entry. If yes, set EOI on guests's behalf.
* Clear PV EOI in guest memory in any case.
*/
static void apic_sync_pv_eoi_from_guest(struct kvm_vcpu *vcpu,
struct kvm_lapic *apic)
{
bool pending;
int vector;
/*
* PV EOI state is derived from KVM_APIC_PV_EOI_PENDING in host
* and KVM_PV_EOI_ENABLED in guest memory as follows:
*
* KVM_APIC_PV_EOI_PENDING is unset:
* -> host disabled PV EOI.
* KVM_APIC_PV_EOI_PENDING is set, KVM_PV_EOI_ENABLED is set:
* -> host enabled PV EOI, guest did not execute EOI yet.
* KVM_APIC_PV_EOI_PENDING is set, KVM_PV_EOI_ENABLED is unset:
* -> host enabled PV EOI, guest executed EOI.
*/
BUG_ON(!pv_eoi_enabled(vcpu));
pending = pv_eoi_get_pending(vcpu);
/*
* Clear pending bit in any case: it will be set again on vmentry.
* While this might not be ideal from performance point of view,
* this makes sure pv eoi is only enabled when we know it's safe.
*/
pv_eoi_clr_pending(vcpu);
if (pending)
return;
vector = apic_set_eoi(apic);
trace_kvm_pv_eoi(apic, vector);
}
void kvm_lapic_sync_from_vapic(struct kvm_vcpu *vcpu)
{
u32 data;
if (test_bit(KVM_APIC_PV_EOI_PENDING, &vcpu->arch.apic_attention))
apic_sync_pv_eoi_from_guest(vcpu, vcpu->arch.apic);
if (!test_bit(KVM_APIC_CHECK_VAPIC, &vcpu->arch.apic_attention))
return;
if (kvm_read_guest_cached(vcpu->kvm, &vcpu->arch.apic->vapic_cache, &data,
sizeof(u32)))
return;
apic_set_tpr(vcpu->arch.apic, data & 0xff);
}
/*
* apic_sync_pv_eoi_to_guest - called before vmentry
*
* Detect whether it's safe to enable PV EOI and
* if yes do so.
*/
static void apic_sync_pv_eoi_to_guest(struct kvm_vcpu *vcpu,
struct kvm_lapic *apic)
{
if (!pv_eoi_enabled(vcpu) ||
/* IRR set or many bits in ISR: could be nested. */
apic->irr_pending ||
/* Cache not set: could be safe but we don't bother. */
apic->highest_isr_cache == -1 ||
/* Need EOI to update ioapic. */
kvm_ioapic_handles_vector(apic, apic->highest_isr_cache)) {
/*
* PV EOI was disabled by apic_sync_pv_eoi_from_guest
* so we need not do anything here.
*/
return;
}
pv_eoi_set_pending(apic->vcpu);
}
void kvm_lapic_sync_to_vapic(struct kvm_vcpu *vcpu)
{
u32 data, tpr;
int max_irr, max_isr;
struct kvm_lapic *apic = vcpu->arch.apic;
apic_sync_pv_eoi_to_guest(vcpu, apic);
if (!test_bit(KVM_APIC_CHECK_VAPIC, &vcpu->arch.apic_attention))
return;
tpr = kvm_lapic_get_reg(apic, APIC_TASKPRI) & 0xff;
max_irr = apic_find_highest_irr(apic);
if (max_irr < 0)
max_irr = 0;
max_isr = apic_find_highest_isr(apic);
if (max_isr < 0)
max_isr = 0;
data = (tpr & 0xff) | ((max_isr & 0xf0) << 8) | (max_irr << 24);
kvm_write_guest_cached(vcpu->kvm, &vcpu->arch.apic->vapic_cache, &data,
sizeof(u32));
}
int kvm_lapic_set_vapic_addr(struct kvm_vcpu *vcpu, gpa_t vapic_addr)
{
if (vapic_addr) {
if (kvm_gfn_to_hva_cache_init(vcpu->kvm,
&vcpu->arch.apic->vapic_cache,
vapic_addr, sizeof(u32)))
return -EINVAL;
__set_bit(KVM_APIC_CHECK_VAPIC, &vcpu->arch.apic_attention);
} else {
__clear_bit(KVM_APIC_CHECK_VAPIC, &vcpu->arch.apic_attention);
}
vcpu->arch.apic->vapic_addr = vapic_addr;
return 0;
}
int kvm_x2apic_msr_write(struct kvm_vcpu *vcpu, u32 msr, u64 data)
{
struct kvm_lapic *apic = vcpu->arch.apic;
u32 reg = (msr - APIC_BASE_MSR) << 4;
if (!lapic_in_kernel(vcpu) || !apic_x2apic_mode(apic))
return 1;
if (reg == APIC_ICR2)
return 1;
/* if this is ICR write vector before command */
if (reg == APIC_ICR)
kvm_lapic_reg_write(apic, APIC_ICR2, (u32)(data >> 32));
return kvm_lapic_reg_write(apic, reg, (u32)data);
}
int kvm_x2apic_msr_read(struct kvm_vcpu *vcpu, u32 msr, u64 *data)
{
struct kvm_lapic *apic = vcpu->arch.apic;
u32 reg = (msr - APIC_BASE_MSR) << 4, low, high = 0;
if (!lapic_in_kernel(vcpu) || !apic_x2apic_mode(apic))
return 1;
if (reg == APIC_DFR || reg == APIC_ICR2) {
apic_debug("KVM_APIC_READ: read x2apic reserved register %x\n",
reg);
return 1;
}
if (kvm_lapic_reg_read(apic, reg, 4, &low))
return 1;
if (reg == APIC_ICR)
kvm_lapic_reg_read(apic, APIC_ICR2, 4, &high);
*data = (((u64)high) << 32) | low;
return 0;
}
int kvm_hv_vapic_msr_write(struct kvm_vcpu *vcpu, u32 reg, u64 data)
{
struct kvm_lapic *apic = vcpu->arch.apic;
if (!lapic_in_kernel(vcpu))
return 1;
/* if this is ICR write vector before command */
if (reg == APIC_ICR)
kvm_lapic_reg_write(apic, APIC_ICR2, (u32)(data >> 32));
return kvm_lapic_reg_write(apic, reg, (u32)data);
}
int kvm_hv_vapic_msr_read(struct kvm_vcpu *vcpu, u32 reg, u64 *data)
{
struct kvm_lapic *apic = vcpu->arch.apic;
u32 low, high = 0;
if (!lapic_in_kernel(vcpu))
return 1;
if (kvm_lapic_reg_read(apic, reg, 4, &low))
return 1;
if (reg == APIC_ICR)
kvm_lapic_reg_read(apic, APIC_ICR2, 4, &high);
*data = (((u64)high) << 32) | low;
return 0;
}
int kvm_lapic_enable_pv_eoi(struct kvm_vcpu *vcpu, u64 data)
{
u64 addr = data & ~KVM_MSR_ENABLED;
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));
}
void kvm_apic_accept_events(struct kvm_vcpu *vcpu)
{
struct kvm_lapic *apic = vcpu->arch.apic;
u8 sipi_vector;
unsigned long pe;
if (!lapic_in_kernel(vcpu) || !apic->pending_events)
return;
/*
* INITs are latched while in SMM. Because an SMM CPU cannot
* be in KVM_MP_STATE_INIT_RECEIVED state, just eat SIPIs
* and delay processing of INIT until the next RSM.
*/
if (is_smm(vcpu)) {
WARN_ON_ONCE(vcpu->arch.mp_state == KVM_MP_STATE_INIT_RECEIVED);
if (test_bit(KVM_APIC_SIPI, &apic->pending_events))
clear_bit(KVM_APIC_SIPI, &apic->pending_events);
return;
}
pe = xchg(&apic->pending_events, 0);
if (test_bit(KVM_APIC_INIT, &pe)) {
kvm_lapic_reset(vcpu, true);
kvm_vcpu_reset(vcpu, true);
if (kvm_vcpu_is_bsp(apic->vcpu))
vcpu->arch.mp_state = KVM_MP_STATE_RUNNABLE;
else
vcpu->arch.mp_state = KVM_MP_STATE_INIT_RECEIVED;
}
if (test_bit(KVM_APIC_SIPI, &pe) &&
vcpu->arch.mp_state == KVM_MP_STATE_INIT_RECEIVED) {
/* evaluate pending_events before reading the vector */
smp_rmb();
sipi_vector = apic->sipi_vector;
apic_debug("vcpu %d received sipi with vector # %x\n",
vcpu->vcpu_id, sipi_vector);
kvm_vcpu_deliver_sipi_vector(vcpu, sipi_vector);
vcpu->arch.mp_state = KVM_MP_STATE_RUNNABLE;
}
}
void kvm_lapic_init(void)
{
/* do not patch jump label more than once per second */
jump_label_rate_limit(&apic_hw_disabled, HZ);
jump_label_rate_limit(&apic_sw_disabled, HZ);
}