mirrors/linux-stable
1
0
Fork 0
mirror of https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git synced 2024-11-01 00:48:50 +00:00
Code Issues Releases Wiki Activity
linux-stable/arch/x86/kvm/lapic.c
Gleb Natapov 17d68b763f KVM: x86: fix guest-initiated crash with x2apic (CVE-2013-6376) 
A guest can cause a BUG_ON() leading to a host kernel crash.
When the guest writes to the ICR to request an IPI, while in x2apic
mode the following things happen, the destination is read from
ICR2, which is a register that the guest can control.

kvm_irq_delivery_to_apic_fast uses the high 16 bits of ICR2 as the
cluster id.  A BUG_ON is triggered, which is a protection against
accessing map->logical_map with an out-of-bounds access and manages
to avoid that anything really unsafe occurs.

The logic in the code is correct from real HW point of view. The problem
is that KVM supports only one cluster with ID 0 in clustered mode, but
the code that has the bug does not take this into account.

Reported-by: Lars Bull <larsbull@google.com>
Cc: stable@vger.kernel.org
Signed-off-by: Gleb Natapov <gleb@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2013-12-12 22:46:18 +01:00

1889 lines
46 KiB
C
Raw Blame History

/*
* 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 <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"
#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...)
#define APIC_LVT_NUM 6
/* 14 is the version for Xeon and Pentium 8.4.8*/
#define APIC_VERSION (0x14UL | ((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 VEC_POS(v) ((v) & (32 - 1))
#define REG_POS(v) (((v) >> 5) << 4)
static unsigned int min_timer_period_us = 500;
module_param(min_timer_period_us, uint, S_IRUGO | S_IWUSR);
static inline void apic_set_reg(struct kvm_lapic *apic, int reg_off, u32 val)
{
*((u32 *) (apic->regs + reg_off)) = val;
}
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_set_vector(int vec, void *bitmap)
{
set_bit(VEC_POS(vec), (bitmap) + REG_POS(vec));
}
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 void apic_set_spiv(struct kvm_lapic *apic, u32 val)
{
if ((kvm_apic_get_reg(apic, APIC_SPIV) ^ val) & APIC_SPIV_APIC_ENABLED) {
if (val & APIC_SPIV_APIC_ENABLED)
static_key_slow_dec_deferred(&apic_sw_disabled);
else
static_key_slow_inc(&apic_sw_disabled.key);
}
apic_set_reg(apic, APIC_SPIV, val);
}
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)
static inline int kvm_apic_id(struct kvm_lapic *apic)
{
return (kvm_apic_get_reg(apic, APIC_ID) >> 24) & 0xff;
}
#define KVM_X2APIC_CID_BITS 0
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;
new->ldr_bits = 8;
/* flat mode is default */
new->cid_shift = 8;
new->cid_mask = 0;
new->lid_mask = 0xff;
kvm_for_each_vcpu(i, vcpu, kvm) {
struct kvm_lapic *apic = vcpu->arch.apic;
u16 cid, lid;
u32 ldr;
if (!kvm_apic_present(vcpu))
continue;
/*
* All APICs have to be configured in the same mode by an OS.
* We take advatage of this while building logical id loockup
* table. After reset APICs are in xapic/flat mode, so if we
* find apic with different setting we assume this is the mode
* OS wants all apics to be in; build lookup table accordingly.
*/
if (apic_x2apic_mode(apic)) {
new->ldr_bits = 32;
new->cid_shift = 16;
new->cid_mask = (1 << KVM_X2APIC_CID_BITS) - 1;
new->lid_mask = 0xffff;
} else if (kvm_apic_sw_enabled(apic) &&
!new->cid_mask /* flat mode */ &&
kvm_apic_get_reg(apic, APIC_DFR) == APIC_DFR_CLUSTER) {
new->cid_shift = 4;
new->cid_mask = 0xf;
new->lid_mask = 0xf;
}
new->phys_map[kvm_apic_id(apic)] = apic;
ldr = kvm_apic_get_reg(apic, APIC_LDR);
cid = apic_cluster_id(new, ldr);
lid = apic_logical_id(new, ldr);
if (lid)
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_vcpu_request_scan_ioapic(kvm);
}
static inline void kvm_apic_set_id(struct kvm_lapic *apic, u8 id)
{
apic_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)
{
apic_set_reg(apic, APIC_LDR, id);
recalculate_apic_map(apic->vcpu->kvm);
}
static inline int apic_lvt_enabled(struct kvm_lapic *apic, int lvt_type)
{
return !(kvm_apic_get_reg(apic, lvt_type) & APIC_LVT_MASKED);
}
static inline int apic_lvt_vector(struct kvm_lapic *apic, int lvt_type)
{
return kvm_apic_get_reg(apic, lvt_type) & APIC_VECTOR_MASK;
}
static inline int apic_lvtt_oneshot(struct kvm_lapic *apic)
{
return ((kvm_apic_get_reg(apic, APIC_LVTT) &
apic->lapic_timer.timer_mode_mask) == APIC_LVT_TIMER_ONESHOT);
}
static inline int apic_lvtt_period(struct kvm_lapic *apic)
{
return ((kvm_apic_get_reg(apic, APIC_LVTT) &
apic->lapic_timer.timer_mode_mask) == APIC_LVT_TIMER_PERIODIC);
}
static inline int apic_lvtt_tscdeadline(struct kvm_lapic *apic)
{
return ((kvm_apic_get_reg(apic, APIC_LVTT) &
apic->lapic_timer.timer_mode_mask) ==
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 (!kvm_vcpu_has_lapic(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;
apic_set_reg(apic, APIC_LVR, v);
}
static const unsigned int apic_lvt_mask[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(struct kvm_vcpu *vcpu, u32 *pir)
{
u32 i, pir_val;
struct kvm_lapic *apic = vcpu->arch.apic;
for (i = 0; i <= 7; i++) {
pir_val = xchg(&pir[i], 0);
if (pir_val)
*((u32 *)(apic->regs + APIC_IRR + i * 0x10)) |= pir_val;
}
}
EXPORT_SYMBOL_GPL(kvm_apic_update_irr);
static inline void apic_set_irr(int vec, struct kvm_lapic *apic)
{
apic->irr_pending = true;
apic_set_vector(vec, apic->regs + APIC_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;
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)
{
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)
{
if (!__apic_test_and_set_vector(vec, apic->regs + APIC_ISR))
++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 void apic_clear_isr(int vec, struct kvm_lapic *apic)
{
if (__apic_test_and_clear_vector(vec, apic->regs + APIC_ISR))
--apic->isr_count;
BUG_ON(apic->isr_count < 0);
apic->highest_isr_cache = -1;
}
int kvm_lapic_find_highest_irr(struct kvm_vcpu *vcpu)
{
int highest_irr;
/* 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.
*/
if (!kvm_vcpu_has_lapic(vcpu))
return 0;
highest_irr = apic_find_highest_irr(vcpu->arch.apic);
return highest_irr;
}
static int __apic_accept_irq(struct kvm_lapic *apic, int delivery_mode,
int vector, int level, int trig_mode,
unsigned long *dest_map);
int kvm_apic_set_irq(struct kvm_vcpu *vcpu, struct kvm_lapic_irq *irq,
unsigned long *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)vcpi->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)vcpi->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)vcpi->arch.pv_eoi.msr_val);
return;
}
__clear_bit(KVM_APIC_PV_EOI_PENDING, &vcpu->arch.apic_attention);
}
static inline int apic_find_highest_isr(struct kvm_lapic *apic)
{
int result;
/* Note that isr_count is always 1 with vid 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;
}
void kvm_apic_update_tmr(struct kvm_vcpu *vcpu, u32 *tmr)
{
struct kvm_lapic *apic = vcpu->arch.apic;
int i;
for (i = 0; i < 8; i++)
apic_set_reg(apic, APIC_TMR + 0x10 * i, tmr[i]);
}
static void apic_update_ppr(struct kvm_lapic *apic)
{
u32 tpr, isrv, ppr, old_ppr;
int isr;
old_ppr = kvm_apic_get_reg(apic, APIC_PROCPRI);
tpr = kvm_apic_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) {
apic_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)
{
apic_set_reg(apic, APIC_TASKPRI, tpr);
apic_update_ppr(apic);
}
int kvm_apic_match_physical_addr(struct kvm_lapic *apic, u16 dest)
{
return dest == 0xff || kvm_apic_id(apic) == dest;
}
int kvm_apic_match_logical_addr(struct kvm_lapic *apic, u8 mda)
{
int result = 0;
u32 logical_id;
if (apic_x2apic_mode(apic)) {
logical_id = kvm_apic_get_reg(apic, APIC_LDR);
return logical_id & mda;
}
logical_id = GET_APIC_LOGICAL_ID(kvm_apic_get_reg(apic, APIC_LDR));
switch (kvm_apic_get_reg(apic, APIC_DFR)) {
case APIC_DFR_FLAT:
if (logical_id & mda)
result = 1;
break;
case APIC_DFR_CLUSTER:
if (((logical_id >> 4) == (mda >> 0x4))
&& (logical_id & mda & 0xf))
result = 1;
break;
default:
apic_debug("Bad DFR vcpu %d: %08x\n",
apic->vcpu->vcpu_id, kvm_apic_get_reg(apic, APIC_DFR));
break;
}
return result;
}
int kvm_apic_match_dest(struct kvm_vcpu *vcpu, struct kvm_lapic *source,
int short_hand, int dest, int dest_mode)
{
int result = 0;
struct kvm_lapic *target = vcpu->arch.apic;
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 == 0)
/* Physical mode. */
result = kvm_apic_match_physical_addr(target, dest);
else
/* Logical mode. */
result = kvm_apic_match_logical_addr(target, dest);
break;
case APIC_DEST_SELF:
result = (target == source);
break;
case APIC_DEST_ALLINC:
result = 1;
break;
case APIC_DEST_ALLBUT:
result = (target != source);
break;
default:
apic_debug("kvm: apic: Bad dest shorthand value %x\n",
short_hand);
break;
}
return result;
}
bool kvm_irq_delivery_to_apic_fast(struct kvm *kvm, struct kvm_lapic *src,
struct kvm_lapic_irq *irq, int *r, unsigned long *dest_map)
{
struct kvm_apic_map *map;
unsigned long bitmap = 1;
struct kvm_lapic **dst;
int i;
bool ret = false;
*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;
rcu_read_lock();
map = rcu_dereference(kvm->arch.apic_map);
if (!map)
goto out;
if (irq->dest_mode == 0) { /* physical mode */
if (irq->delivery_mode == APIC_DM_LOWEST ||
irq->dest_id == 0xff)
goto out;
dst = &map->phys_map[irq->dest_id & 0xff];
} else {
u32 mda = irq->dest_id << (32 - map->ldr_bits);
dst = map->logical_map[apic_cluster_id(map, mda)];
bitmap = apic_logical_id(map, mda);
if (irq->delivery_mode == APIC_DM_LOWEST) {
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;
}
}
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);
}
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,
unsigned long *dest_map)
{
int result = 0;
struct kvm_vcpu *vcpu = apic->vcpu;
switch (delivery_mode) {
case APIC_DM_LOWEST:
vcpu->arch.apic_arb_prio++;
case APIC_DM_FIXED:
/* 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);
if (kvm_x86_ops->deliver_posted_interrupt)
kvm_x86_ops->deliver_posted_interrupt(vcpu, vector);
else {
apic_set_irr(vector, apic);
kvm_make_request(KVM_REQ_EVENT, vcpu);
kvm_vcpu_kick(vcpu);
}
trace_kvm_apic_accept_irq(vcpu->vcpu_id, delivery_mode,
trig_mode, vector, false);
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:
apic_debug("Ignoring guest SMI\n");
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 void kvm_ioapic_send_eoi(struct kvm_lapic *apic, int vector)
{
if (!(kvm_apic_get_reg(apic, APIC_SPIV) & APIC_SPIV_DIRECTED_EOI) &&
kvm_ioapic_handles_vector(apic->vcpu->kvm, vector)) {
int trigger_mode;
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);
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_apic_get_reg(apic, APIC_ICR);
u32 icr_high = kvm_apic_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;
irq.trig_mode = icr_low & APIC_INT_LEVELTRIG;
irq.shorthand = icr_low & APIC_SHORT_MASK;
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\n",
icr_high, icr_low, irq.shorthand, irq.dest_id,
irq.trig_mode, irq.level, irq.dest_mode, irq.delivery_mode,
irq.vector);
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_apic_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_apic_get_reg(apic, offset);
break;
case APIC_TASKPRI:
report_tpr_access(apic, false);
/* fall thru */
default:
val = kvm_apic_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);
}
static int apic_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;
}
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_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;
apic_reg_read(apic, offset, len, data);
return 0;
}
static void update_divide_count(struct kvm_lapic *apic)
{
u32 tmp1, tmp2, tdcr;
tdcr = kvm_apic_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 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_apic_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);
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_apic_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;
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_x86_ops->read_l1_tsc(vcpu, native_read_tsc());
if (likely(tscdeadline > guest_tsc)) {
ns = (tscdeadline - guest_tsc) * 1000000ULL;
do_div(ns, this_tsc_khz);
}
hrtimer_start(&apic->lapic_timer.timer,
ktime_add_ns(now, ns), HRTIMER_MODE_ABS);
local_irq_restore(flags);
}
}
static void apic_manage_nmi_watchdog(struct kvm_lapic *apic, u32 lvt0_val)
{
int nmi_wd_enabled = apic_lvt_nmi_mode(kvm_apic_get_reg(apic, APIC_LVT0));
if (apic_lvt_nmi_mode(lvt0_val)) {
if (!nmi_wd_enabled) {
apic_debug("Receive NMI setting on APIC_LVT0 "
"for cpu %d\n", apic->vcpu->vcpu_id);
apic->vcpu->kvm->arch.vapics_in_nmi_mode++;
}
} else if (nmi_wd_enabled)
apic->vcpu->kvm->arch.vapics_in_nmi_mode--;
}
static int apic_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)) {
apic_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_apic_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 < APIC_LVT_NUM; i++) {
lvt_val = kvm_apic_get_reg(apic,
APIC_LVTT + 0x10 * i);
apic_set_reg(apic, APIC_LVTT + 0x10 * i,
lvt_val | APIC_LVT_MASKED);
}
atomic_set(&apic->lapic_timer.pending, 0);
}
break;
}
case APIC_ICR:
/* No delay here, so we always clear the pending bit */
apic_set_reg(apic, APIC_ICR, val & ~(1 << 12));
apic_send_ipi(apic);
break;
case APIC_ICR2:
if (!apic_x2apic_mode(apic))
val &= 0xff000000;
apic_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];
apic_set_reg(apic, reg, val);
break;
case APIC_LVTT:
if ((kvm_apic_get_reg(apic, APIC_LVTT) &
apic->lapic_timer.timer_mode_mask) !=
(val & apic->lapic_timer.timer_mode_mask))
hrtimer_cancel(&apic->lapic_timer.timer);
if (!kvm_apic_sw_enabled(apic))
val |= APIC_LVT_MASKED;
val &= (apic_lvt_mask[0] | apic->lapic_timer.timer_mode_mask);
apic_set_reg(apic, APIC_LVTT, val);
break;
case APIC_TMICT:
if (apic_lvtt_tscdeadline(apic))
break;
hrtimer_cancel(&apic->lapic_timer.timer);
apic_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);
apic_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)) {
apic_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;
}
static int apic_mmio_write(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);
apic_reg_write(apic, offset & 0xff0, val);
return 0;
}
void kvm_lapic_set_eoi(struct kvm_vcpu *vcpu)
{
if (kvm_vcpu_has_lapic(vcpu))
apic_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;
apic_reg_read(vcpu->arch.apic, offset, 4, &val);
/* TODO: optimize to just emulate side effect w/o one more write */
apic_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 (!(kvm_apic_get_reg(apic, APIC_SPIV) & APIC_SPIV_APIC_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 (!kvm_vcpu_has_lapic(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 (!kvm_vcpu_has_lapic(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;
if (!kvm_vcpu_has_lapic(vcpu))
return;
apic_set_tpr(apic, ((cr8 & 0x0f) << 4)
| (kvm_apic_get_reg(apic, APIC_TASKPRI) & 4));
}
u64 kvm_lapic_get_cr8(struct kvm_vcpu *vcpu)
{
u64 tpr;
if (!kvm_vcpu_has_lapic(vcpu))
return 0;
tpr = (u64) kvm_apic_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;
}
/* update jump label if enable bit changes */
if ((vcpu->arch.apic_base ^ 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 (!kvm_vcpu_is_bsp(apic->vcpu))
value &= ~MSR_IA32_APICBASE_BSP;
vcpu->arch.apic_base = value;
if ((old_value ^ value) & X2APIC_ENABLE) {
if (value & X2APIC_ENABLE) {
u32 id = kvm_apic_id(apic);
u32 ldr = ((id >> 4) << 16) | (1 << (id & 0xf));
kvm_apic_set_ldr(apic, ldr);
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;
/* 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)
{
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);
kvm_apic_set_id(apic, vcpu->vcpu_id);
kvm_apic_set_version(apic->vcpu);
for (i = 0; i < APIC_LVT_NUM; i++)
apic_set_reg(apic, APIC_LVTT + 0x10 * i, APIC_LVT_MASKED);
apic_set_reg(apic, APIC_LVT0,
SET_APIC_DELIVERY_MODE(0, APIC_MODE_EXTINT));
apic_set_reg(apic, APIC_DFR, 0xffffffffU);
apic_set_spiv(apic, 0xff);
apic_set_reg(apic, APIC_TASKPRI, 0);
kvm_apic_set_ldr(apic, 0);
apic_set_reg(apic, APIC_ESR, 0);
apic_set_reg(apic, APIC_ICR, 0);
apic_set_reg(apic, APIC_ICR2, 0);
apic_set_reg(apic, APIC_TDCR, 0);
apic_set_reg(apic, APIC_TMICT, 0);
for (i = 0; i < 8; i++) {
apic_set_reg(apic, APIC_IRR + 0x10 * i, 0);
apic_set_reg(apic, APIC_ISR + 0x10 * i, 0);
apic_set_reg(apic, APIC_TMR + 0x10 * i, 0);
}
apic->irr_pending = kvm_apic_vid_enabled(vcpu->kvm);
apic->isr_count = kvm_apic_vid_enabled(vcpu->kvm);
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(KERN_INFO "%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 (kvm_vcpu_has_lapic(vcpu) && 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_apic_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);
struct kvm_vcpu *vcpu = apic->vcpu;
wait_queue_head_t *q = &vcpu->wq;
/*
* There is a race window between reading and incrementing, but we do
* not care about potentially losing timer events in the !reinject
* case anyway. Note: KVM_REQ_PENDING_TIMER is implicitly checked
* in vcpu_enter_guest.
*/
if (!atomic_read(&ktimer->pending)) {
atomic_inc(&ktimer->pending);
/* FIXME: this code should not know anything about vcpus */
kvm_make_request(KVM_REQ_PENDING_TIMER, vcpu);
}
if (waitqueue_active(q))
wake_up_interruptible(q);
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);
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);
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 (!kvm_vcpu_has_lapic(vcpu) || !apic_enabled(apic))
return -1;
apic_update_ppr(apic);
highest_irr = apic_find_highest_irr(apic);
if ((highest_irr == -1) ||
((highest_irr & 0xF0) <= kvm_apic_get_reg(apic, APIC_PROCPRI)))
return -1;
return highest_irr;
}
int kvm_apic_accept_pic_intr(struct kvm_vcpu *vcpu)
{
u32 lvt0 = kvm_apic_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 (!kvm_vcpu_has_lapic(vcpu))
return;
if (atomic_read(&apic->lapic_timer.pending) > 0) {
kvm_apic_local_deliver(apic, APIC_LVTT);
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;
apic_set_isr(vector, apic);
apic_update_ppr(apic);
apic_clear_irr(vector, 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);
update_divide_count(apic);
start_apic_timer(apic);
apic->irr_pending = true;
apic->isr_count = kvm_apic_vid_enabled(vcpu->kvm) ?
1 : count_vectors(apic->regs + APIC_ISR);
apic->highest_isr_cache = -1;
kvm_x86_ops->hwapic_isr_update(vcpu->kvm, apic_find_highest_isr(apic));
kvm_make_request(KVM_REQ_EVENT, vcpu);
kvm_rtc_eoi_tracking_restore_one(vcpu);
}
void __kvm_migrate_apic_timer(struct kvm_vcpu *vcpu)
{
struct hrtimer *timer;
if (!kvm_vcpu_has_lapic(vcpu))
return;
timer = &vcpu->arch.apic->lapic_timer.timer;
if (hrtimer_cancel(timer))
hrtimer_start_expires(timer, HRTIMER_MODE_ABS);
}
/*
* 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;
kvm_read_guest_cached(vcpu->kvm, &vcpu->arch.apic->vapic_cache, &data,
sizeof(u32));
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(vcpu->kvm, 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_apic_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 (!irqchip_in_kernel(vcpu->kvm) || !apic_x2apic_mode(apic))
return 1;
/* if this is ICR write vector before command */
if (msr == 0x830)
apic_reg_write(apic, APIC_ICR2, (u32)(data >> 32));
return apic_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 (!irqchip_in_kernel(vcpu->kvm) || !apic_x2apic_mode(apic))
return 1;
if (apic_reg_read(apic, reg, 4, &low))
return 1;
if (msr == 0x830)
apic_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 (!kvm_vcpu_has_lapic(vcpu))
return 1;
/* if this is ICR write vector before command */
if (reg == APIC_ICR)
apic_reg_write(apic, APIC_ICR2, (u32)(data >> 32));
return apic_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 (!kvm_vcpu_has_lapic(vcpu))
return 1;
if (apic_reg_read(apic, reg, 4, &low))
return 1;
if (reg == APIC_ICR)
apic_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;
unsigned int sipi_vector;
unsigned long pe;
if (!kvm_vcpu_has_lapic(vcpu) || !apic->pending_events)
return;
pe = xchg(&apic->pending_events, 0);
if (test_bit(KVM_APIC_INIT, &pe)) {
kvm_lapic_reset(vcpu);
kvm_vcpu_reset(vcpu);
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;
pr_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);
}
Reference in a new issue View git blame Copy permalink