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zircon-guest/third_party/linux/refs/heads/master/./arch/x86/kvm/lapic.c
blob: ecf611845fb12d6a76a3231035b5788d47140707 [file] [edit]
// SPDX-License-Identifier: GPL-2.0-only
/*
* 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.
*/
#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
#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/export.h>
#include <linux/math64.h>
#include <linux/slab.h>
#include <asm/apic.h>
#include <asm/processor.h>
#include <asm/mce.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 "regs.h"
#include "irq.h"
#include "ioapic.h"
#include "trace.h"
#include "x86.h"
#include "xen.h"
#include "cpuid.h"
#include "hyperv.h"
#include "smm.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
/* 14 is the version for Xeon and Pentium 8.4.8*/
#define APIC_VERSION 0x14UL
#define LAPIC_MMIO_LENGTH (1 << 12)
/*
* Enable local APIC timer advancement (tscdeadline mode only) with adaptive
* tuning. When enabled, KVM programs the host timer event to fire early, i.e.
* before the deadline expires, to account for the delay between taking the
* VM-Exit (to inject the guest event) and the subsequent VM-Enter to resume
* the guest, i.e. so that the interrupt arrives in the guest with minimal
* latency relative to the deadline programmed by the guest.
*/
static bool lapic_timer_advance __read_mostly = true;
module_param(lapic_timer_advance, bool, 0444);
#define LAPIC_TIMER_ADVANCE_ADJUST_MIN 100 /* clock cycles */
#define LAPIC_TIMER_ADVANCE_ADJUST_MAX 10000 /* clock cycles */
#define LAPIC_TIMER_ADVANCE_NS_INIT 1000
#define LAPIC_TIMER_ADVANCE_NS_MAX 5000
/* step-by-step approximation to mitigate fluctuation */
#define LAPIC_TIMER_ADVANCE_ADJUST_STEP 8
/* apic attention bits */
#define KVM_APIC_CHECK_VAPIC 0
/*
* The following bit is set with PV-EOI, unset on EOI.
* We detect PV-EOI changes by guest by comparing
* this bit with PV-EOI in guest memory.
* See the implementation in apic_update_pv_eoi.
*/
#define KVM_APIC_PV_EOI_PENDING 1
static bool __read_mostly vector_hashing_enabled = true;
module_param_named(vector_hashing, vector_hashing_enabled, bool, 0444);
static int kvm_lapic_msr_read(struct kvm_lapic *apic, u32 reg, u64 *data);
static int kvm_lapic_msr_write(struct kvm_lapic *apic, u32 reg, u64 data);
static inline void kvm_lapic_set_reg(struct kvm_lapic *apic, int reg_off, u32 val)
{
apic_set_reg(apic->regs, reg_off, val);
}
static __always_inline u64 kvm_lapic_get_reg64(struct kvm_lapic *apic, int reg)
{
return apic_get_reg64(apic->regs, reg);
}
static __always_inline void kvm_lapic_set_reg64(struct kvm_lapic *apic,
int reg, u64 val)
{
apic_set_reg64(apic->regs, reg, val);
}
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 bool kvm_lapic_advertise_suppress_eoi_broadcast(struct kvm *kvm)
{
switch (kvm->arch.suppress_eoi_broadcast_mode) {
case KVM_SUPPRESS_EOI_BROADCAST_ENABLED:
return true;
case KVM_SUPPRESS_EOI_BROADCAST_DISABLED:
return false;
case KVM_SUPPRESS_EOI_BROADCAST_QUIRKED:
/*
* The default in-kernel I/O APIC emulates the 82093AA and does not
* implement an EOI register. Some guests (e.g. Windows with the
* Hyper-V role enabled) disable LAPIC EOI broadcast without
* checking the I/O APIC version, which can cause level-triggered
* interrupts to never be EOI'd.
*
* To avoid this, KVM doesn't advertise Suppress EOI Broadcast
* support when using the default in-kernel I/O APIC.
*
* Historically, in split IRQCHIP mode, KVM always advertised
* Suppress EOI Broadcast support but did not actually suppress
* EOIs, resulting in quirky behavior.
*/
return !ioapic_in_kernel(kvm);
default:
WARN_ON_ONCE(1);
return false;
}
}
bool kvm_lapic_suppress_eoi_broadcast(struct kvm_lapic *apic)
{
struct kvm *kvm = apic->vcpu->kvm;
if (!(kvm_lapic_get_reg(apic, APIC_SPIV) & APIC_SPIV_DIRECTED_EOI))
return false;
switch (kvm->arch.suppress_eoi_broadcast_mode) {
case KVM_SUPPRESS_EOI_BROADCAST_ENABLED:
return true;
case KVM_SUPPRESS_EOI_BROADCAST_DISABLED:
return false;
case KVM_SUPPRESS_EOI_BROADCAST_QUIRKED:
/*
* Historically, in split IRQCHIP mode, KVM ignored the suppress
* EOI broadcast bit set by the guest and broadcasts EOIs to the
* userspace I/O APIC. For In-kernel I/O APIC, the support itself
* is not advertised, can only be enabled via KVM_SET_APIC_STATE,
* and KVM's I/O APIC doesn't emulate Directed EOIs; but if the
* feature is enabled, it is respected (with odd behavior).
*/
return ioapic_in_kernel(kvm);
default:
WARN_ON_ONCE(1);
return false;
}
}
__read_mostly DEFINE_STATIC_KEY_FALSE(kvm_has_noapic_vcpu);
EXPORT_SYMBOL_FOR_KVM_INTERNAL(kvm_has_noapic_vcpu);
__read_mostly DEFINE_STATIC_KEY_DEFERRED_FALSE(apic_hw_disabled, HZ);
__read_mostly DEFINE_STATIC_KEY_DEFERRED_FALSE(apic_sw_disabled, HZ);
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 u32 kvm_x2apic_id(struct kvm_lapic *apic)
{
return apic->vcpu->vcpu_id;
}
static bool kvm_can_post_timer_interrupt(struct kvm_vcpu *vcpu)
{
return pi_inject_timer && kvm_vcpu_apicv_active(vcpu) &&
(kvm_mwait_in_guest(vcpu->kvm) || kvm_hlt_in_guest(vcpu->kvm));
}
static bool kvm_can_use_hv_timer(struct kvm_vcpu *vcpu)
{
return kvm_x86_ops.set_hv_timer
&& !(kvm_mwait_in_guest(vcpu->kvm) ||
kvm_can_post_timer_interrupt(vcpu));
}
static bool kvm_use_posted_timer_interrupt(struct kvm_vcpu *vcpu)
{
return kvm_can_post_timer_interrupt(vcpu) && vcpu->mode == IN_GUEST_MODE;
}
static inline u32 kvm_apic_calc_x2apic_ldr(u32 id)
{
return ((id >> 4) << 16) | (1 << (id & 0xf));
}
static inline bool kvm_apic_map_get_logical_dest(struct kvm_apic_map *map,
u32 dest_id, struct kvm_lapic ***cluster, u16 *mask) {
switch (map->logical_mode) {
case KVM_APIC_MODE_SW_DISABLED:
/* Arbitrarily use the flat map so that @cluster isn't NULL. */
*cluster = map->xapic_flat_map;
*mask = 0;
return true;
case KVM_APIC_MODE_X2APIC: {
u32 offset = (dest_id >> 16) * 16;
u32 max_apic_id = map->max_apic_id;
if (offset <= max_apic_id) {
u8 cluster_size = min(max_apic_id - offset + 1, 16U);
offset = array_index_nospec(offset, map->max_apic_id + 1);
*cluster = &map->phys_map[offset];
*mask = dest_id & (0xffff >> (16 - cluster_size));
} else {
*mask = 0;
}
return true;
}
case KVM_APIC_MODE_XAPIC_FLAT:
*cluster = map->xapic_flat_map;
*mask = dest_id & 0xff;
return true;
case KVM_APIC_MODE_XAPIC_CLUSTER:
*cluster = map->xapic_cluster_map[(dest_id >> 4) & 0xf];
*mask = dest_id & 0xf;
return true;
case KVM_APIC_MODE_MAP_DISABLED:
return false;
default:
WARN_ON_ONCE(1);
return false;
}
}
static int kvm_recalculate_phys_map(struct kvm_apic_map *new,
struct kvm_vcpu *vcpu,
bool *xapic_id_mismatch)
{
struct kvm_lapic *apic = vcpu->arch.apic;
u32 x2apic_id = kvm_x2apic_id(apic);
u32 xapic_id = kvm_xapic_id(apic);
u32 physical_id;
/*
* For simplicity, KVM always allocates enough space for all possible
* xAPIC IDs. Yell, but don't kill the VM, as KVM can continue on
* without the optimized map.
*/
if (WARN_ON_ONCE(xapic_id > new->max_apic_id))
return -EINVAL;
/*
* Bail if a vCPU was added and/or enabled its APIC between allocating
* the map and doing the actual calculations for the map. Note, KVM
* hardcodes the x2APIC ID to vcpu_id, i.e. there's no TOCTOU bug if
* the compiler decides to reload x2apic_id after this check.
*/
if (x2apic_id > new->max_apic_id)
return -E2BIG;
/*
* Deliberately truncate the vCPU ID when detecting a mismatched APIC
* ID to avoid false positives if the vCPU ID, i.e. x2APIC ID, is a
* 32-bit value. Any unwanted aliasing due to truncation results will
* be detected below.
*/
if (!apic_x2apic_mode(apic) && xapic_id != (u8)vcpu->vcpu_id)
*xapic_id_mismatch = true;
/*
* Apply KVM's hotplug hack if userspace has enable 32-bit APIC IDs.
* Allow sending events to vCPUs by their x2APIC ID even if the target
* vCPU is in legacy xAPIC mode, and silently ignore aliased xAPIC IDs
* (the x2APIC ID is truncated to 8 bits, causing IDs > 0xff to wrap
* and collide).
*
* Honor the architectural (and KVM's non-optimized) behavior if
* userspace has not enabled 32-bit x2APIC IDs. Each APIC is supposed
* to process messages independently. If multiple vCPUs have the same
* effective APIC ID, e.g. due to the x2APIC wrap or because the guest
* manually modified its xAPIC IDs, events targeting that ID are
* supposed to be recognized by all vCPUs with said ID.
*/
if (vcpu->kvm->arch.x2apic_format) {
/* See also kvm_apic_match_physical_addr(). */
if (apic_x2apic_mode(apic) || x2apic_id > 0xff)
new->phys_map[x2apic_id] = apic;
if (!apic_x2apic_mode(apic) && !new->phys_map[xapic_id])
new->phys_map[xapic_id] = apic;
} else {
/*
* Disable the optimized map if the physical APIC ID is already
* mapped, i.e. is aliased to multiple vCPUs. The optimized
* map requires a strict 1:1 mapping between IDs and vCPUs.
*/
if (apic_x2apic_mode(apic))
physical_id = x2apic_id;
else
physical_id = xapic_id;
if (new->phys_map[physical_id])
return -EINVAL;
new->phys_map[physical_id] = apic;
}
return 0;
}
static void kvm_recalculate_logical_map(struct kvm_apic_map *new,
struct kvm_vcpu *vcpu)
{
struct kvm_lapic *apic = vcpu->arch.apic;
enum kvm_apic_logical_mode logical_mode;
struct kvm_lapic **cluster;
u16 mask;
u32 ldr;
if (new->logical_mode == KVM_APIC_MODE_MAP_DISABLED)
return;
if (!kvm_apic_sw_enabled(apic))
return;
ldr = kvm_lapic_get_reg(apic, APIC_LDR);
if (!ldr)
return;
if (apic_x2apic_mode(apic)) {
logical_mode = KVM_APIC_MODE_X2APIC;
} else {
ldr = GET_APIC_LOGICAL_ID(ldr);
if (kvm_lapic_get_reg(apic, APIC_DFR) == APIC_DFR_FLAT)
logical_mode = KVM_APIC_MODE_XAPIC_FLAT;
else
logical_mode = KVM_APIC_MODE_XAPIC_CLUSTER;
}
/*
* To optimize logical mode delivery, all software-enabled APICs must
* be configured for the same mode.
*/
if (new->logical_mode == KVM_APIC_MODE_SW_DISABLED) {
new->logical_mode = logical_mode;
} else if (new->logical_mode != logical_mode) {
new->logical_mode = KVM_APIC_MODE_MAP_DISABLED;
return;
}
/*
* In x2APIC mode, the LDR is read-only and derived directly from the
* x2APIC ID, thus is guaranteed to be addressable. KVM reuses
* kvm_apic_map.phys_map to optimize logical mode x2APIC interrupts by
* reversing the LDR calculation to get cluster of APICs, i.e. no
* additional work is required.
*/
if (apic_x2apic_mode(apic))
return;
if (WARN_ON_ONCE(!kvm_apic_map_get_logical_dest(new, ldr,
&cluster, &mask))) {
new->logical_mode = KVM_APIC_MODE_MAP_DISABLED;
return;
}
if (!mask)
return;
ldr = ffs(mask) - 1;
if (!is_power_of_2(mask) || cluster[ldr])
new->logical_mode = KVM_APIC_MODE_MAP_DISABLED;
else
cluster[ldr] = apic;
}
/*
* CLEAN -> DIRTY and UPDATE_IN_PROGRESS -> DIRTY changes happen without a lock.
*
* DIRTY -> UPDATE_IN_PROGRESS and UPDATE_IN_PROGRESS -> CLEAN happen with
* apic_map_lock_held.
*/
enum {
CLEAN,
UPDATE_IN_PROGRESS,
DIRTY
};
static void kvm_recalculate_apic_map(struct kvm *kvm)
{
struct kvm_apic_map *new, *old = NULL;
struct kvm_vcpu *vcpu;
unsigned long i;
u32 max_id = 255; /* enough space for any xAPIC ID */
bool xapic_id_mismatch;
int r;
/* Read kvm->arch.apic_map_dirty before kvm->arch.apic_map. */
if (atomic_read_acquire(&kvm->arch.apic_map_dirty) == CLEAN)
return;
WARN_ONCE(!irqchip_in_kernel(kvm),
"Dirty APIC map without an in-kernel local APIC");
mutex_lock(&kvm->arch.apic_map_lock);
retry:
/*
* Read kvm->arch.apic_map_dirty before kvm->arch.apic_map (if clean)
* or the APIC registers (if dirty). Note, on retry the map may have
* not yet been marked dirty by whatever task changed a vCPU's x2APIC
* ID, i.e. the map may still show up as in-progress. In that case
* this task still needs to retry and complete its calculation.
*/
if (atomic_cmpxchg_acquire(&kvm->arch.apic_map_dirty,
DIRTY, UPDATE_IN_PROGRESS) == CLEAN) {
/* Someone else has updated the map. */
mutex_unlock(&kvm->arch.apic_map_lock);
return;
}
/*
* Reset the mismatch flag between attempts so that KVM does the right
* thing if a vCPU changes its xAPIC ID, but do NOT reset max_id, i.e.
* keep max_id strictly increasing. Disallowing max_id from shrinking
* ensures KVM won't get stuck in an infinite loop, e.g. if the vCPU
* with the highest x2APIC ID is toggling its APIC on and off.
*/
xapic_id_mismatch = false;
kvm_for_each_vcpu(i, vcpu, kvm)
if (kvm_apic_present(vcpu))
max_id = max(max_id, kvm_x2apic_id(vcpu->arch.apic));
new = kvzalloc(sizeof(struct kvm_apic_map) +
sizeof(struct kvm_lapic *) * ((u64)max_id + 1),
GFP_KERNEL_ACCOUNT);
if (!new)
goto out;
new->max_apic_id = max_id;
new->logical_mode = KVM_APIC_MODE_SW_DISABLED;
kvm_for_each_vcpu(i, vcpu, kvm) {
if (!kvm_apic_present(vcpu))
continue;
r = kvm_recalculate_phys_map(new, vcpu, &xapic_id_mismatch);
if (r) {
kvfree(new);
new = NULL;
if (r == -E2BIG) {
cond_resched();
goto retry;
}
goto out;
}
kvm_recalculate_logical_map(new, vcpu);
}
out:
/*
* The optimized map is effectively KVM's internal version of APICv,
* and all unwanted aliasing that results in disabling the optimized
* map also applies to APICv.
*/
if (!new)
kvm_set_apicv_inhibit(kvm, APICV_INHIBIT_REASON_PHYSICAL_ID_ALIASED);
else
kvm_clear_apicv_inhibit(kvm, APICV_INHIBIT_REASON_PHYSICAL_ID_ALIASED);
if (!new || new->logical_mode == KVM_APIC_MODE_MAP_DISABLED)
kvm_set_apicv_inhibit(kvm, APICV_INHIBIT_REASON_LOGICAL_ID_ALIASED);
else
kvm_clear_apicv_inhibit(kvm, APICV_INHIBIT_REASON_LOGICAL_ID_ALIASED);
if (xapic_id_mismatch)
kvm_set_apicv_inhibit(kvm, APICV_INHIBIT_REASON_APIC_ID_MODIFIED);
else
kvm_clear_apicv_inhibit(kvm, APICV_INHIBIT_REASON_APIC_ID_MODIFIED);
old = rcu_dereference_protected(kvm->arch.apic_map,
lockdep_is_held(&kvm->arch.apic_map_lock));
rcu_assign_pointer(kvm->arch.apic_map, new);
/*
* Write kvm->arch.apic_map before clearing apic->apic_map_dirty.
* If another update has come in, leave it DIRTY.
*/
atomic_cmpxchg_release(&kvm->arch.apic_map_dirty,
UPDATE_IN_PROGRESS, CLEAN);
mutex_unlock(&kvm->arch.apic_map_lock);
if (old)
kvfree_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_branch_slow_dec_deferred(&apic_sw_disabled);
else
static_branch_inc(&apic_sw_disabled.key);
atomic_set_release(&apic->vcpu->kvm->arch.apic_map_dirty, DIRTY);
}
/* Check if there are APF page ready requests pending */
if (enabled) {
kvm_make_request(KVM_REQ_APF_READY, apic->vcpu);
kvm_xen_sw_enable_lapic(apic->vcpu);
}
}
static inline void kvm_apic_set_xapic_id(struct kvm_lapic *apic, u8 id)
{
kvm_lapic_set_reg(apic, APIC_ID, id << 24);
atomic_set_release(&apic->vcpu->kvm->arch.apic_map_dirty, DIRTY);
}
static inline void kvm_apic_set_ldr(struct kvm_lapic *apic, u32 id)
{
kvm_lapic_set_reg(apic, APIC_LDR, id);
atomic_set_release(&apic->vcpu->kvm->arch.apic_map_dirty, DIRTY);
}
static inline void kvm_apic_set_dfr(struct kvm_lapic *apic, u32 val)
{
kvm_lapic_set_reg(apic, APIC_DFR, val);
atomic_set_release(&apic->vcpu->kvm->arch.apic_map_dirty, DIRTY);
}
static inline void kvm_apic_set_x2apic_id(struct kvm_lapic *apic, u32 id)
{
u32 ldr = kvm_apic_calc_x2apic_ldr(id);
WARN_ON_ONCE(id != apic->vcpu->vcpu_id);
kvm_lapic_set_reg(apic, APIC_ID, id);
kvm_lapic_set_reg(apic, APIC_LDR, ldr);
atomic_set_release(&apic->vcpu->kvm->arch.apic_map_dirty, DIRTY);
}
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_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;
}
static inline bool kvm_lapic_lvt_supported(struct kvm_lapic *apic, int lvt_index)
{
return apic->nr_lvt_entries > lvt_index;
}
static inline int kvm_apic_calc_nr_lvt_entries(struct kvm_vcpu *vcpu)
{
return KVM_APIC_MAX_NR_LVT_ENTRIES - !(vcpu->arch.mcg_cap & MCG_CMCI_P);
}
void kvm_apic_set_version(struct kvm_vcpu *vcpu)
{
struct kvm_lapic *apic = vcpu->arch.apic;
u32 v = 0;
if (!lapic_in_kernel(vcpu))
return;
v = APIC_VERSION | ((apic->nr_lvt_entries - 1) << 16);
if (guest_cpu_cap_has(vcpu, X86_FEATURE_X2APIC) &&
kvm_lapic_advertise_suppress_eoi_broadcast(vcpu->kvm))
v |= APIC_LVR_DIRECTED_EOI;
kvm_lapic_set_reg(apic, APIC_LVR, v);
}
void kvm_apic_after_set_mcg_cap(struct kvm_vcpu *vcpu)
{
int nr_lvt_entries = kvm_apic_calc_nr_lvt_entries(vcpu);
struct kvm_lapic *apic = vcpu->arch.apic;
int i;
if (!lapic_in_kernel(vcpu) || nr_lvt_entries == apic->nr_lvt_entries)
return;
/* Initialize/mask any "new" LVT entries. */
for (i = apic->nr_lvt_entries; i < nr_lvt_entries; i++)
kvm_lapic_set_reg(apic, APIC_LVTx(i), APIC_LVT_MASKED);
apic->nr_lvt_entries = nr_lvt_entries;
/* The number of LVT entries is reflected in the version register. */
kvm_apic_set_version(vcpu);
}
static const unsigned int apic_lvt_mask[KVM_APIC_MAX_NR_LVT_ENTRIES] = {
[LVT_TIMER] = LVT_MASK, /* timer mode mask added at runtime */
[LVT_THERMAL_MONITOR] = LVT_MASK | APIC_MODE_MASK,
[LVT_PERFORMANCE_COUNTER] = LVT_MASK | APIC_MODE_MASK,
[LVT_LINT0] = LINT_MASK,
[LVT_LINT1] = LINT_MASK,
[LVT_ERROR] = LVT_MASK,
[LVT_CMCI] = LVT_MASK | APIC_MODE_MASK
};
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 + APIC_VECTOR_TO_REG_OFFSET(vec);
count += hweight32(*reg);
}
return count;
}
bool __kvm_apic_update_irr(unsigned long *pir, void *regs, int *max_irr)
{
unsigned long pir_vals[NR_PIR_WORDS];
u32 *__pir = (void *)pir_vals;
u32 i, vec;
u32 irr_val, prev_irr_val;
int max_new_irr;
if (!pi_harvest_pir(pir, pir_vals)) {
*max_irr = apic_find_highest_vector(regs + APIC_IRR);
return false;
}
max_new_irr = -1;
*max_irr = -1;
for (i = vec = 0; i <= 7; i++, vec += 32) {
u32 *p_irr = (u32 *)(regs + APIC_IRR + i * 0x10);
irr_val = READ_ONCE(*p_irr);
if (__pir[i]) {
prev_irr_val = irr_val;
do {
irr_val = prev_irr_val | __pir[i];
} while (prev_irr_val != irr_val &&
!try_cmpxchg(p_irr, &prev_irr_val, irr_val));
if (prev_irr_val != irr_val)
max_new_irr = __fls(irr_val ^ prev_irr_val) + vec;
}
if (irr_val)
*max_irr = __fls(irr_val) + vec;
}
return max_new_irr != -1 && max_new_irr == *max_irr;
}
EXPORT_SYMBOL_FOR_KVM_INTERNAL(__kvm_apic_update_irr);
bool kvm_apic_update_irr(struct kvm_vcpu *vcpu, unsigned long *pir, int *max_irr)
{
struct kvm_lapic *apic = vcpu->arch.apic;
bool max_irr_is_from_pir;
max_irr_is_from_pir = __kvm_apic_update_irr(pir, apic->regs, max_irr);
if (unlikely(!apic->apicv_active && max_irr_is_from_pir))
apic->irr_pending = true;
return max_irr_is_from_pir;
}
EXPORT_SYMBOL_FOR_KVM_INTERNAL(kvm_apic_update_irr);
static inline int apic_search_irr(struct kvm_lapic *apic)
{
return apic_find_highest_vector(apic->regs + APIC_IRR);
}
static inline int apic_find_highest_irr(struct kvm_lapic *apic)
{
/*
* Note that irr_pending is just a hint. It will be always
* true with virtual interrupt delivery enabled.
*/
if (!apic->irr_pending)
return -1;
return apic_search_irr(apic);
}
static inline void apic_clear_irr(int vec, struct kvm_lapic *apic)
{
if (unlikely(apic->apicv_active)) {
apic_clear_vector(vec, apic->regs + APIC_IRR);
} else {
apic->irr_pending = false;
apic_clear_vector(vec, apic->regs + APIC_IRR);
if (apic_search_irr(apic) != -1)
apic->irr_pending = true;
}
}
void kvm_apic_clear_irr(struct kvm_vcpu *vcpu, int vec)
{
apic_clear_irr(vec, vcpu->arch.apic);
}
EXPORT_SYMBOL_FOR_KVM_INTERNAL(kvm_apic_clear_irr);
static void *apic_vector_to_isr(int vec, struct kvm_lapic *apic)
{
return apic->regs + APIC_ISR + APIC_VECTOR_TO_REG_OFFSET(vec);
}
static inline void apic_set_isr(int vec, struct kvm_lapic *apic)
{
if (__test_and_set_bit(APIC_VECTOR_TO_BIT_NUMBER(vec),
apic_vector_to_isr(vec, apic)))
return;
/*
* With APIC virtualization enabled, all caching is disabled
* because the processor can modify ISR under the hood. Instead
* just set SVI.
*/
if (unlikely(apic->apicv_active))
kvm_x86_call(hwapic_isr_update)(apic->vcpu, vec);
else {
++apic->isr_count;
KVM_BUG_ON(apic->isr_count > MAX_APIC_VECTOR, apic->vcpu->kvm);
/*
* 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)
{
/*
* 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;
return apic_find_highest_vector(apic->regs + APIC_ISR);
}
static inline void apic_clear_isr(int vec, struct kvm_lapic *apic)
{
if (!__test_and_clear_bit(APIC_VECTOR_TO_BIT_NUMBER(vec),
apic_vector_to_isr(vec, apic)))
return;
/*
* 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(apic->apicv_active))
kvm_x86_call(hwapic_isr_update)(apic->vcpu, apic_find_highest_isr(apic));
else {
--apic->isr_count;
KVM_BUG_ON(apic->isr_count < 0, apic->vcpu->kvm);
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);
}
EXPORT_SYMBOL_FOR_KVM_INTERNAL(kvm_lapic_find_highest_irr);
static int __apic_accept_irq(struct kvm_lapic *apic, int delivery_mode,
int vector, int level, int trig_mode,
struct rtc_status *rtc_status);
int kvm_apic_set_irq(struct kvm_vcpu *vcpu, struct kvm_lapic_irq *irq,
struct rtc_status *rtc_status)
{
struct kvm_lapic *apic = vcpu->arch.apic;
return __apic_accept_irq(apic, irq->delivery_mode, irq->vector,
irq->level, irq->trig_mode, rtc_status);
}
static int __pv_send_ipi(unsigned long *ipi_bitmap, struct kvm_apic_map *map,
struct kvm_lapic_irq *irq, u32 min)
{
int i, count = 0;
struct kvm_vcpu *vcpu;
size_t map_index;
if (min > map->max_apic_id)
return 0;
for_each_set_bit(i, ipi_bitmap,
min((u32)BITS_PER_LONG, (map->max_apic_id - min + 1))) {
map_index = array_index_nospec(min + i, map->max_apic_id + 1);
if (map->phys_map[map_index]) {
vcpu = map->phys_map[map_index]->vcpu;
count += kvm_apic_set_irq(vcpu, irq, NULL);
}
}
return count;
}
int kvm_pv_send_ipi(struct kvm *kvm, unsigned long ipi_bitmap_low,
unsigned long ipi_bitmap_high, u32 min,
unsigned long icr, int op_64_bit)
{
struct kvm_apic_map *map;
struct kvm_lapic_irq irq = {0};
int cluster_size = op_64_bit ? 64 : 32;
int count;
if (icr & (APIC_DEST_MASK | APIC_SHORT_MASK))
return -KVM_EINVAL;
irq.vector = icr & APIC_VECTOR_MASK;
irq.delivery_mode = icr & APIC_MODE_MASK;
irq.level = (icr & APIC_INT_ASSERT) != 0;
irq.trig_mode = icr & APIC_INT_LEVELTRIG;
rcu_read_lock();
map = rcu_dereference(kvm->arch.apic_map);
count = -EOPNOTSUPP;
if (likely(map)) {
count = __pv_send_ipi(&ipi_bitmap_low, map, &irq, min);
min += cluster_size;
count += __pv_send_ipi(&ipi_bitmap_high, map, &irq, min);
}
rcu_read_unlock();
return count;
}
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 void pv_eoi_set_pending(struct kvm_vcpu *vcpu)
{
if (pv_eoi_put_user(vcpu, KVM_PV_EOI_ENABLED) < 0)
return;
__set_bit(KVM_APIC_PV_EOI_PENDING, &vcpu->arch.apic_attention);
}
static bool pv_eoi_test_and_clr_pending(struct kvm_vcpu *vcpu)
{
u8 val;
if (pv_eoi_get_user(vcpu, &val) < 0)
return false;
val &= KVM_PV_EOI_ENABLED;
if (val && pv_eoi_put_user(vcpu, KVM_PV_EOI_DISABLED) < 0)
return false;
/*
* 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.
*/
__clear_bit(KVM_APIC_PV_EOI_PENDING, &vcpu->arch.apic_attention);
return val;
}
static int apic_has_interrupt_for_ppr(struct kvm_lapic *apic, u32 ppr)
{
int highest_irr;
if (kvm_x86_ops.sync_pir_to_irr)
highest_irr = kvm_x86_call(sync_pir_to_irr)(apic->vcpu);
else
highest_irr = apic_find_highest_irr(apic);
if (highest_irr == -1 || (highest_irr & 0xF0) <= ppr)
return -1;
return highest_irr;
}
static bool __apic_update_ppr(struct kvm_lapic *apic, u32 *new_ppr)
{
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;
*new_ppr = ppr;
if (old_ppr != ppr)
kvm_lapic_set_reg(apic, APIC_PROCPRI, ppr);
return ppr < old_ppr;
}
static void apic_update_ppr(struct kvm_lapic *apic)
{
u32 ppr;
if (__apic_update_ppr(apic, &ppr) &&
apic_has_interrupt_for_ppr(apic, ppr) != -1)
kvm_make_request(KVM_REQ_EVENT, apic->vcpu);
else
kvm_lapic_update_cr8_intercept(apic->vcpu);
}
void kvm_apic_update_ppr(struct kvm_vcpu *vcpu)
{
apic_update_ppr(vcpu->arch.apic);
}
EXPORT_SYMBOL_FOR_KVM_INTERNAL(kvm_apic_update_ppr);
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)
{
return mda == (apic_x2apic_mode(apic) ?
X2APIC_BROADCAST : APIC_BROADCAST);
}
static bool kvm_apic_match_physical_addr(struct kvm_lapic *apic, u32 mda)
{
if (kvm_apic_broadcast(apic, mda))
return true;
/*
* Hotplug hack: Accept interrupts for vCPUs in xAPIC mode as if they
* were in x2APIC mode if the target APIC ID can't be encoded as an
* xAPIC ID. This allows unique addressing of hotplugged vCPUs (which
* start in xAPIC mode) with an APIC ID that is unaddressable in xAPIC
* mode. Match the x2APIC ID if and only if the target APIC ID can't
* be encoded in xAPIC to avoid spurious matches against a vCPU that
* changed its (addressable) xAPIC ID (which is writable).
*/
if (apic_x2apic_mode(apic) || mda > 0xff)
return mda == kvm_x2apic_id(apic);
return mda == kvm_xapic_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);
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:
return false;
}
}
/* The KVM local APIC implementation has two quirks:
*
* - Real hardware delivers interrupts destined to x2APIC ID > 0xff to LAPICs
* in xAPIC mode if the "destination & 0xff" matches its xAPIC ID.
* KVM doesn't do that aliasing.
*
* - in-kernel IOAPIC messages have to be delivered directly to
* x2APIC, because the kernel does not support interrupt remapping.
* In order to support broadcast without interrupt remapping, x2APIC
* rewrites the destination of non-IPI messages from APIC_BROADCAST
* to X2APIC_BROADCAST.
*
* The broadcast quirk can be disabled with KVM_CAP_X2APIC_API. This is
* important when userspace wants to use x2APIC-format MSIs, because
* APIC_BROADCAST (0xff) is a legal route for "cluster 0, CPUs 0-7".
*/
static u32 kvm_apic_mda(struct kvm_vcpu *vcpu, unsigned int dest_id,
struct kvm_lapic *source, struct kvm_lapic *target)
{
bool ipi = source != NULL;
if (!vcpu->kvm->arch.x2apic_broadcast_quirk_disabled &&
!ipi && dest_id == APIC_BROADCAST && apic_x2apic_mode(target))
return X2APIC_BROADCAST;
return dest_id;
}
bool kvm_apic_match_dest(struct kvm_vcpu *vcpu, struct kvm_lapic *source,
int shorthand, unsigned int dest, int dest_mode)
{
struct kvm_lapic *target = vcpu->arch.apic;
u32 mda = kvm_apic_mda(vcpu, dest, source, target);
switch (shorthand) {
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:
return false;
}
}
EXPORT_SYMBOL_FOR_KVM_INTERNAL(kvm_apic_match_dest);
static int kvm_vector_to_index(u32 vector, u32 dest_vcpus,
const unsigned long *bitmap, u32 bitmap_size)
{
int idx = find_nth_bit(bitmap, bitmap_size, vector % dest_vcpus);
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;
pr_info("Disabled LAPIC found during irq injection\n");
}
}
static bool kvm_apic_is_broadcast_dest(struct kvm *kvm, struct kvm_lapic **src,
struct kvm_lapic_irq *irq, struct kvm_apic_map *map)
{
if (kvm->arch.x2apic_broadcast_quirk_disabled) {
if ((irq->dest_id == APIC_BROADCAST &&
map->logical_mode != KVM_APIC_MODE_X2APIC))
return true;
if (irq->dest_id == X2APIC_BROADCAST)
return true;
} else {
bool x2apic_ipi = src && *src && apic_x2apic_mode(*src);
if (irq->dest_id == (x2apic_ipi ?
X2APIC_BROADCAST : APIC_BROADCAST))
return true;
}
return false;
}
static bool kvm_lowest_prio_delivery(struct kvm_lapic_irq *irq)
{
return (irq->delivery_mode == APIC_DM_LOWEST || irq->msi_redir_hint);
}
static int kvm_apic_compare_prio(struct kvm_vcpu *vcpu1, struct kvm_vcpu *vcpu2)
{
return vcpu1->arch.apic_arb_prio - vcpu2->arch.apic_arb_prio;
}
/* Return true if the interrupt can be handled by using *bitmap as index mask
* for valid destinations in *dst array.
* Return false if kvm_apic_map_get_dest_lapic did nothing useful.
* Note: we may have zero kvm_lapic destinations when we return true, which
* means that the interrupt should be dropped. In this case, *bitmap would be
* zero and *dst undefined.
*/
static inline bool kvm_apic_map_get_dest_lapic(struct kvm *kvm,
struct kvm_lapic **src, struct kvm_lapic_irq *irq,
struct kvm_apic_map *map, struct kvm_lapic ***dst,
unsigned long *bitmap)
{
int i, lowest;
if (irq->shorthand == APIC_DEST_SELF && src) {
*dst = src;
*bitmap = 1;
return true;
} else if (irq->shorthand)
return false;
if (!map || kvm_apic_is_broadcast_dest(kvm, src, irq, map))
return false;
if (irq->dest_mode == APIC_DEST_PHYSICAL) {
if (irq->dest_id > map->max_apic_id) {
*bitmap = 0;
} else {
u32 dest_id = array_index_nospec(irq->dest_id, map->max_apic_id + 1);
*dst = &map->phys_map[dest_id];
*bitmap = 1;
}
return true;
}
*bitmap = 0;
if (!kvm_apic_map_get_logical_dest(map, irq->dest_id, dst,
(u16 *)bitmap))
return false;
if (!kvm_lowest_prio_delivery(irq))
return true;
if (!vector_hashing_enabled) {
lowest = -1;
for_each_set_bit(i, bitmap, 16) {
if (!(*dst)[i])
continue;
if (lowest < 0)
lowest = i;
else if (kvm_apic_compare_prio((*dst)[i]->vcpu,
(*dst)[lowest]->vcpu) < 0)
lowest = i;
}
} else {
if (!*bitmap)
return true;
lowest = kvm_vector_to_index(irq->vector, hweight16(*bitmap),
bitmap, 16);
if (!(*dst)[lowest]) {
kvm_apic_disabled_lapic_found(kvm);
*bitmap = 0;
return true;
}
}
*bitmap = (lowest >= 0) ? 1 << lowest : 0;
return true;
}
static bool __kvm_irq_delivery_to_apic_fast(struct kvm *kvm, struct kvm_lapic *src,
struct kvm_lapic_irq *irq, int *r,
struct rtc_status *rtc_status)
{
struct kvm_apic_map *map;
unsigned long bitmap;
struct kvm_lapic **dst = NULL;
int i;
bool ret;
*r = -1;
if (irq->shorthand == APIC_DEST_SELF) {
if (KVM_BUG_ON(!src, kvm)) {
*r = 0;
return true;
}
*r = kvm_apic_set_irq(src->vcpu, irq, rtc_status);
return true;
}
rcu_read_lock();
map = rcu_dereference(kvm->arch.apic_map);
ret = kvm_apic_map_get_dest_lapic(kvm, &src, irq, map, &dst, &bitmap);
if (ret) {
*r = 0;
for_each_set_bit(i, &bitmap, 16) {
if (!dst[i])
continue;
*r += kvm_apic_set_irq(dst[i]->vcpu, irq, rtc_status);
}
}
rcu_read_unlock();
return ret;
}
bool kvm_irq_delivery_to_apic_fast(struct kvm *kvm, struct kvm_lapic *src,
struct kvm_lapic_irq *irq, int *r)
{
return __kvm_irq_delivery_to_apic_fast(kvm, src, irq, r, NULL);
}
/*
* This routine tries to handle 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 destination 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.
*/
static 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;
unsigned long bitmap;
struct kvm_lapic **dst = NULL;
bool ret = false;
if (irq->shorthand)
return false;
rcu_read_lock();
map = rcu_dereference(kvm->arch.apic_map);
if (kvm_apic_map_get_dest_lapic(kvm, NULL, irq, map, &dst, &bitmap) &&
hweight16(bitmap) == 1) {
unsigned long i = find_first_bit(&bitmap, 16);
if (dst[i]) {
*dest_vcpu = dst[i]->vcpu;
ret = true;
}
}
rcu_read_unlock();
return ret;
}
bool kvm_intr_is_single_vcpu(struct kvm *kvm, struct kvm_lapic_irq *irq,
struct kvm_vcpu **dest_vcpu)
{
int r = 0;
unsigned long i;
struct kvm_vcpu *vcpu;
if (kvm_intr_is_single_vcpu_fast(kvm, irq, dest_vcpu))
return true;
kvm_for_each_vcpu(i, vcpu, kvm) {
if (!kvm_apic_present(vcpu))
continue;
if (!kvm_apic_match_dest(vcpu, NULL, irq->shorthand,
irq->dest_id, irq->dest_mode))
continue;
if (++r == 2)
return false;
*dest_vcpu = vcpu;
}
return r == 1;
}
EXPORT_SYMBOL_FOR_KVM_INTERNAL(kvm_intr_is_single_vcpu);
int __kvm_irq_delivery_to_apic(struct kvm *kvm, struct kvm_lapic *src,
struct kvm_lapic_irq *irq,
struct rtc_status *rtc_status)
{
int r = -1;
struct kvm_vcpu *vcpu, *lowest = NULL;
unsigned long i, dest_vcpu_bitmap[BITS_TO_LONGS(KVM_MAX_VCPUS)];
unsigned int dest_vcpus = 0;
if (__kvm_irq_delivery_to_apic_fast(kvm, src, irq, &r, rtc_status))
return r;
if (irq->dest_mode == APIC_DEST_PHYSICAL &&
irq->dest_id == 0xff && kvm_lowest_prio_delivery(irq)) {
pr_info("apic: phys broadcast and lowest prio\n");
irq->delivery_mode = APIC_DM_FIXED;
}
memset(dest_vcpu_bitmap, 0, sizeof(dest_vcpu_bitmap));
kvm_for_each_vcpu(i, vcpu, kvm) {
if (!kvm_apic_present(vcpu))
continue;
if (!kvm_apic_match_dest(vcpu, src, irq->shorthand,
irq->dest_id, irq->dest_mode))
continue;
if (!kvm_lowest_prio_delivery(irq)) {
if (r < 0)
r = 0;
r += kvm_apic_set_irq(vcpu, irq, rtc_status);
} else if (kvm_apic_sw_enabled(vcpu->arch.apic)) {
if (!vector_hashing_enabled) {
if (!lowest)
lowest = vcpu;
else if (kvm_apic_compare_prio(vcpu, lowest) < 0)
lowest = vcpu;
} else {
__set_bit(i, dest_vcpu_bitmap);
dest_vcpus++;
}
}
}
if (dest_vcpus != 0) {
int idx = kvm_vector_to_index(irq->vector, dest_vcpus,
dest_vcpu_bitmap, KVM_MAX_VCPUS);
lowest = kvm_get_vcpu(kvm, idx);
}
if (lowest)
r = kvm_apic_set_irq(lowest, irq, rtc_status);
return r;
}
/*
* 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 rtc_status *rtc_status)
{
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++;
fallthrough;
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;
#ifdef CONFIG_KVM_IOAPIC
if (rtc_status) {
__set_bit(vcpu->vcpu_id, rtc_status->map);
rtc_status->vectors[vcpu->vcpu_id] = vector;
}
#endif
if (apic_test_vector(vector, apic->regs + APIC_TMR) != !!trig_mode) {
if (trig_mode)
apic_set_vector(vector, apic->regs + APIC_TMR);
else
apic_clear_vector(vector, apic->regs + APIC_TMR);
}
kvm_x86_call(deliver_interrupt)(apic, delivery_mode,
trig_mode, vector);
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:
if (!kvm_inject_smi(vcpu)) {
kvm_vcpu_kick(vcpu);
result = 1;
}
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);
kvm_make_request(KVM_REQ_EVENT, vcpu);
kvm_vcpu_kick(vcpu);
}
break;
case APIC_DM_STARTUP:
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:
WARN_ON_ONCE(1);
break;
}
return result;
}
/*
* This routine identifies the destination vcpus mask meant to receive the
* IOAPIC interrupts. It either uses kvm_apic_map_get_dest_lapic() to find
* out the destination vcpus array and set the bitmap or it traverses to
* each available vcpu to identify the same.
*/
void kvm_bitmap_or_dest_vcpus(struct kvm *kvm, struct kvm_lapic_irq *irq,
unsigned long *vcpu_bitmap)
{
struct kvm_lapic **dest_vcpu = NULL;
struct kvm_lapic *src = NULL;
struct kvm_apic_map *map;
struct kvm_vcpu *vcpu;
unsigned long bitmap, i;
int vcpu_idx;
bool ret;
rcu_read_lock();
map = rcu_dereference(kvm->arch.apic_map);
ret = kvm_apic_map_get_dest_lapic(kvm, &src, irq, map, &dest_vcpu,
&bitmap);
if (ret) {
for_each_set_bit(i, &bitmap, 16) {
if (!dest_vcpu[i])
continue;
vcpu_idx = dest_vcpu[i]->vcpu->vcpu_idx;
__set_bit(vcpu_idx, vcpu_bitmap);
}
} else {
kvm_for_each_vcpu(i, vcpu, kvm) {
if (!kvm_apic_present(vcpu))
continue;
if (!kvm_apic_match_dest(vcpu, NULL,
irq->shorthand,
irq->dest_id,
irq->dest_mode))
continue;
__set_bit(i, vcpu_bitmap);
}
}
rcu_read_unlock();
}
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, u8 vector)
{
int __maybe_unused trigger_mode;
/* Eoi the ioapic only if the ioapic doesn't own the vector. */
if (!kvm_ioapic_handles_vector(apic, vector))
return;
/*
* If the intercepted EOI is for an IRQ that was pending from previous
* routing, then re-scan the I/O APIC routes as EOIs for the IRQ likely
* no longer need to be intercepted.
*/
if (apic->vcpu->arch.highest_stale_pending_ioapic_eoi == vector)
kvm_make_request(KVM_REQ_SCAN_IOAPIC, apic->vcpu);
/* Request a KVM exit to inform the userspace IOAPIC. */
if (irqchip_split(apic->vcpu->kvm)) {
/*
* Don't exit to userspace if the guest has enabled Directed
* EOI, a.k.a. Suppress EOI Broadcasts, in which case the local
* APIC doesn't broadcast EOIs (the guest must EOI the target
* I/O APIC(s) directly).
*/
if (kvm_lapic_suppress_eoi_broadcast(apic))
return;
apic->vcpu->arch.pending_ioapic_eoi = vector;
kvm_make_request(KVM_REQ_IOAPIC_EOI_EXIT, apic->vcpu);
return;
}
#ifdef CONFIG_KVM_IOAPIC
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);
#endif
}
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 (kvm_hv_synic_has_vector(apic->vcpu, vector))
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, u8 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_FOR_KVM_INTERNAL(kvm_apic_set_eoi_accelerated);
static void kvm_icr_to_lapic_irq(struct kvm_lapic *apic, u32 icr_low,
u32 icr_high, struct kvm_lapic_irq *irq)
{
/* KVM has no delay and should always clear the BUSY/PENDING flag. */
WARN_ON_ONCE(icr_low & APIC_ICR_BUSY);
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_XAPIC_DEST_FIELD(icr_high);
}
void kvm_apic_send_ipi(struct kvm_lapic *apic, u32 icr_low, u32 icr_high)
{
struct kvm_lapic_irq irq;
kvm_icr_to_lapic_irq(apic, icr_low, icr_high, &irq);
trace_kvm_apic_ipi(icr_low, irq.dest_id);
kvm_irq_delivery_to_apic(apic->vcpu->kvm, apic, &irq);
}
EXPORT_SYMBOL_FOR_KVM_INTERNAL(kvm_apic_send_ipi);
static u32 apic_get_tmcct(struct kvm_lapic *apic)
{
ktime_t remaining, now;
s64 ns;
/* 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;
now = ktime_get();
remaining = ktime_sub(apic->lapic_timer.target_expiration, now);
if (ktime_to_ns(remaining) < 0)
remaining = 0;
ns = mod_64(ktime_to_ns(remaining), apic->lapic_timer.period);
return div64_u64(ns, (apic->vcpu->kvm->arch.apic_bus_cycle_ns *
apic->divide_count));
}
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_ARBPRI:
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);
fallthrough;
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);
}
#define APIC_REG_MASK(reg) (1ull << ((reg) >> 4))
#define APIC_REGS_MASK(first, count) \
(APIC_REG_MASK(first) * ((1ull << (count)) - 1))
static u64 kvm_lapic_readable_reg_mask(struct kvm_lapic *apic)
{
/* Leave bits '0' for reserved and write-only registers. */
u64 valid_reg_mask =
APIC_REG_MASK(APIC_ID) |
APIC_REG_MASK(APIC_LVR) |
APIC_REG_MASK(APIC_TASKPRI) |
APIC_REG_MASK(APIC_PROCPRI) |
APIC_REG_MASK(APIC_LDR) |
APIC_REG_MASK(APIC_SPIV) |
APIC_REGS_MASK(APIC_ISR, APIC_ISR_NR) |
APIC_REGS_MASK(APIC_TMR, APIC_ISR_NR) |
APIC_REGS_MASK(APIC_IRR, APIC_ISR_NR) |
APIC_REG_MASK(APIC_ESR) |
APIC_REG_MASK(APIC_ICR) |
APIC_REG_MASK(APIC_LVTT) |
APIC_REG_MASK(APIC_LVTTHMR) |
APIC_REG_MASK(APIC_LVTPC) |
APIC_REG_MASK(APIC_LVT0) |
APIC_REG_MASK(APIC_LVT1) |
APIC_REG_MASK(APIC_LVTERR) |
APIC_REG_MASK(APIC_TMICT) |
APIC_REG_MASK(APIC_TMCCT) |
APIC_REG_MASK(APIC_TDCR);
if (kvm_lapic_lvt_supported(apic, LVT_CMCI))
valid_reg_mask |= APIC_REG_MASK(APIC_LVTCMCI);
/* ARBPRI, DFR, and ICR2 are not valid in x2APIC mode. */
if (!apic_x2apic_mode(apic))
valid_reg_mask |= APIC_REG_MASK(APIC_ARBPRI) |
APIC_REG_MASK(APIC_DFR) |
APIC_REG_MASK(APIC_ICR2);
return valid_reg_mask;
}
u64 kvm_x2apic_disable_read_intercept_reg_mask(struct kvm_vcpu *vcpu)
{
if (WARN_ON_ONCE(!lapic_in_kernel(vcpu)))
return 0;
/*
* TMMCT, a.k.a. the current APIC timer count, reads aren't accelerated
* by hardware (Intel or AMD) as the timer is emulated in software (by
* KVM), i.e. reads from the virtual APIC page would return garbage.
* Intercept RDMSR, as handling the fault-like APIC-access VM-Exit is
* more expensive than handling a RDMSR VM-Exit (the APIC-access exit
* requires slow emulation of the code stream).
*/
return kvm_lapic_readable_reg_mask(vcpu->arch.apic) &
~APIC_REG_MASK(APIC_TMCCT);
}
EXPORT_SYMBOL_FOR_KVM_INTERNAL(kvm_x2apic_disable_read_intercept_reg_mask);
static int kvm_lapic_reg_read(struct kvm_lapic *apic, u32 offset, int len,
void *data)
{
unsigned char alignment = offset & 0xf;
u32 result;
/*
* WARN if KVM reads ICR in x2APIC mode, as it's an 8-byte register in
* x2APIC and needs to be manually handled by the caller.
*/
WARN_ON_ONCE(apic_x2apic_mode(apic) && offset == APIC_ICR);
if (alignment + len > 4)
return 1;
if (offset > 0x3f0 ||
!(kvm_lapic_readable_reg_mask(apic) & APIC_REG_MASK(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 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;
if (!kvm_apic_hw_enabled(apic) || apic_x2apic_mode(apic)) {
if (!kvm_check_has_quirk(vcpu->kvm,
KVM_X86_QUIRK_LAPIC_MMIO_HOLE))
return -EOPNOTSUPP;
memset(data, 0xff, len);
return 0;
}
kvm_lapic_reg_read(apic, offset, len, data);
return 0;
}
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);
}
static void limit_periodic_timer_frequency(struct kvm_lapic *apic)
{
/*
* 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) && apic->lapic_timer.period) {
s64 min_period = min_timer_period_us * 1000LL;
if (apic->lapic_timer.period < min_period) {
pr_info_once(
"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;
}
}
}
static void cancel_hv_timer(struct kvm_lapic *apic);
static void cancel_apic_timer(struct kvm_lapic *apic)
{
hrtimer_cancel(&apic->lapic_timer.timer);
preempt_disable();
if (apic->lapic_timer.hv_timer_in_use)
cancel_hv_timer(apic);
preempt_enable();
atomic_set(&apic->lapic_timer.pending, 0);
}
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) {
if (apic_lvtt_tscdeadline(apic) != (timer_mode ==
APIC_LVT_TIMER_TSCDEADLINE)) {
cancel_apic_timer(apic);
kvm_lapic_set_reg(apic, APIC_TMICT, 0);
apic->lapic_timer.period = 0;
apic->lapic_timer.tscdeadline = 0;
}
apic->lapic_timer.timer_mode = timer_mode;
limit_periodic_timer_frequency(apic);
}
}
/*
* 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;
/*
* Assume a timer IRQ was "injected" if the APIC is protected. KVM's
* copy of the vIRR is bogus, it's the responsibility of the caller to
* precisely check whether or not a timer IRQ is pending.
*/
if (apic->guest_apic_protected)
return true;
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 (apic->apicv_active)
bitmap = apic->regs + APIC_IRR;
if (apic_test_vector(vec, bitmap))
return true;
}
return false;
}
static inline void __wait_lapic_expire(struct kvm_vcpu *vcpu, u64 guest_cycles)
{
u64 timer_advance_ns = vcpu->arch.apic->lapic_timer.timer_advance_ns;
/*
* If the guest TSC is running at a different ratio than the host, then
* convert the delay to nanoseconds to achieve an accurate delay. Note
* that __delay() uses delay_tsc whenever the hardware has TSC, thus
* always for VMX enabled hardware.
*/
if (vcpu->arch.tsc_scaling_ratio == kvm_caps.default_tsc_scaling_ratio) {
__delay(min(guest_cycles,
nsec_to_cycles(vcpu, timer_advance_ns)));
} else {
u64 delay_ns = guest_cycles * 1000000ULL;
do_div(delay_ns, vcpu->arch.virtual_tsc_khz);
ndelay(min_t(u32, delay_ns, timer_advance_ns));
}
}
static inline void adjust_lapic_timer_advance(struct kvm_vcpu *vcpu,
s64 advance_expire_delta)
{
struct kvm_lapic *apic = vcpu->arch.apic;
u32 timer_advance_ns = apic->lapic_timer.timer_advance_ns;
u64 ns;
/* Do not adjust for tiny fluctuations or large random spikes. */
if (abs(advance_expire_delta) > LAPIC_TIMER_ADVANCE_ADJUST_MAX ||
abs(advance_expire_delta) < LAPIC_TIMER_ADVANCE_ADJUST_MIN)
return;
/* too early */
if (advance_expire_delta < 0) {
ns = -advance_expire_delta * 1000000ULL;
do_div(ns, vcpu->arch.virtual_tsc_khz);
timer_advance_ns -= ns/LAPIC_TIMER_ADVANCE_ADJUST_STEP;
} else {
/* too late */
ns = advance_expire_delta * 1000000ULL;
do_div(ns, vcpu->arch.virtual_tsc_khz);
timer_advance_ns += ns/LAPIC_TIMER_ADVANCE_ADJUST_STEP;
}
if (unlikely(timer_advance_ns > LAPIC_TIMER_ADVANCE_NS_MAX))
timer_advance_ns = LAPIC_TIMER_ADVANCE_NS_INIT;
apic->lapic_timer.timer_advance_ns = timer_advance_ns;
}
static void __kvm_wait_lapic_expire(struct kvm_vcpu *vcpu)
{
struct kvm_lapic *apic = vcpu->arch.apic;
u64 guest_tsc, tsc_deadline;
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);
adjust_lapic_timer_advance(vcpu, guest_tsc - tsc_deadline);
/*
* If the timer fired early, reread the TSC to account for the overhead
* of the above adjustment to avoid waiting longer than is necessary.
*/
if (guest_tsc < tsc_deadline)
guest_tsc = kvm_read_l1_tsc(vcpu, rdtsc());
if (guest_tsc < tsc_deadline)
__wait_lapic_expire(vcpu, tsc_deadline - guest_tsc);
}
void kvm_wait_lapic_expire(struct kvm_vcpu *vcpu)
{
if (lapic_in_kernel(vcpu) &&
vcpu->arch.apic->lapic_timer.expired_tscdeadline &&
vcpu->arch.apic->lapic_timer.timer_advance_ns &&
lapic_timer_int_injected(vcpu))
__kvm_wait_lapic_expire(vcpu);
}
EXPORT_SYMBOL_FOR_KVM_INTERNAL(kvm_wait_lapic_expire);
static void kvm_apic_inject_pending_timer_irqs(struct kvm_lapic *apic)
{
struct kvm_timer *ktimer = &apic->lapic_timer;
kvm_apic_local_deliver(apic, APIC_LVTT);
if (apic_lvtt_tscdeadline(apic)) {
ktimer->tscdeadline = 0;
} else if (apic_lvtt_oneshot(apic)) {
ktimer->tscdeadline = 0;
ktimer->target_expiration = 0;
}
}
static void apic_timer_expired(struct kvm_lapic *apic, bool from_timer_fn)
{
struct kvm_vcpu *vcpu = apic->vcpu;
struct kvm_timer *ktimer = &apic->lapic_timer;
if (atomic_read(&apic->lapic_timer.pending))
return;
if (apic_lvtt_tscdeadline(apic) || ktimer->hv_timer_in_use)
ktimer->expired_tscdeadline = ktimer->tscdeadline;
if (!from_timer_fn && apic->apicv_active && vcpu->wants_to_run) {
WARN_ON(kvm_get_running_vcpu() != vcpu);
kvm_apic_inject_pending_timer_irqs(apic);
return;
}
if (kvm_use_posted_timer_interrupt(apic->vcpu)) {
/*
* Ensure the guest's timer has truly expired before posting an
* interrupt. Open code the relevant checks to avoid querying
* lapic_timer_int_injected(), which will be false since the
* interrupt isn't yet injected. Waiting until after injecting
* is not an option since that won't help a posted interrupt.
*/
if (vcpu->arch.apic->lapic_timer.expired_tscdeadline &&
vcpu->arch.apic->lapic_timer.timer_advance_ns)
__kvm_wait_lapic_expire(vcpu);
kvm_apic_inject_pending_timer_irqs(apic);
return;
}
atomic_inc(&apic->lapic_timer.pending);
kvm_make_request(KVM_REQ_UNBLOCK, vcpu);
if (from_timer_fn)
kvm_vcpu_kick(vcpu);
}
static void start_sw_tscdeadline(struct kvm_lapic *apic)
{
struct kvm_timer *ktimer = &apic->lapic_timer;
u64 guest_tsc, tscdeadline = ktimer->tscdeadline;
u64 ns = 0;
ktime_t expire;
struct kvm_vcpu *vcpu = apic->vcpu;
u32 this_tsc_khz = vcpu->arch.virtual_tsc_khz;
unsigned long flags;
ktime_t now;
if (unlikely(!tscdeadline || !this_tsc_khz))
return;
local_irq_save(flags);
now = ktime_get();
guest_tsc = kvm_read_l1_tsc(vcpu, rdtsc());
ns = (tscdeadline - guest_tsc) * 1000000ULL;
do_div(ns, this_tsc_khz);
if (likely(tscdeadline > guest_tsc) &&
likely(ns > apic->lapic_timer.timer_advance_ns)) {
expire = ktime_add_ns(now, ns);
expire = ktime_sub_ns(expire, ktimer->timer_advance_ns);
hrtimer_start(&ktimer->timer, expire, HRTIMER_MODE_ABS_HARD);
} else
apic_timer_expired(apic, false);
local_irq_restore(flags);
}
static inline u64 tmict_to_ns(struct kvm_lapic *apic, u32 tmict)
{
return (u64)tmict * apic->vcpu->kvm->arch.apic_bus_cycle_ns *
(u64)apic->divide_count;
}
static void update_target_expiration(struct kvm_lapic *apic, uint32_t old_divisor)
{
ktime_t now, remaining;
u64 ns_remaining_old, ns_remaining_new;
apic->lapic_timer.period =
tmict_to_ns(apic, kvm_lapic_get_reg(apic, APIC_TMICT));
limit_periodic_timer_frequency(apic);
now = ktime_get();
remaining = ktime_sub(apic->lapic_timer.target_expiration, now);
if (ktime_to_ns(remaining) < 0)
remaining = 0;
ns_remaining_old = ktime_to_ns(remaining);
ns_remaining_new = mul_u64_u32_div(ns_remaining_old,
apic->divide_count, old_divisor);
apic->lapic_timer.tscdeadline +=
nsec_to_cycles(apic->vcpu, ns_remaining_new) -
nsec_to_cycles(apic->vcpu, ns_remaining_old);
apic->lapic_timer.target_expiration = ktime_add_ns(now, ns_remaining_new);
}
static bool set_target_expiration(struct kvm_lapic *apic, u32 count_reg)
{
ktime_t now;
u64 tscl = rdtsc();
s64 deadline;
now = ktime_get();
apic->lapic_timer.period =
tmict_to_ns(apic, kvm_lapic_get_reg(apic, APIC_TMICT));
if (!apic->lapic_timer.period) {
apic->lapic_timer.tscdeadline = 0;
return false;
}
limit_periodic_timer_frequency(apic);
deadline = apic->lapic_timer.period;
if (apic_lvtt_period(apic) || apic_lvtt_oneshot(apic)) {
if (unlikely(count_reg != APIC_TMICT)) {
deadline = tmict_to_ns(apic,
kvm_lapic_get_reg(apic, count_reg));
if (unlikely(deadline <= 0)) {
if (apic_lvtt_period(apic))
deadline = apic->lapic_timer.period;
else
deadline = 0;
}
else if (unlikely(deadline > apic->lapic_timer.period)) {
pr_info_ratelimited(
"vcpu %i: requested lapic timer restore with "
"starting count register %#x=%u (%lld ns) > initial count (%lld ns). "
"Using initial count to start timer.\n",
apic->vcpu->vcpu_id,
count_reg,
kvm_lapic_get_reg(apic, count_reg),
deadline, apic->lapic_timer.period);
kvm_lapic_set_reg(apic, count_reg, 0);
deadline = apic->lapic_timer.period;
}
}
}
apic->lapic_timer.tscdeadline = kvm_read_l1_tsc(apic->vcpu, tscl) +
nsec_to_cycles(apic->vcpu, deadline);
apic->lapic_timer.target_expiration = ktime_add_ns(now, deadline);
return true;
}
static void advance_periodic_target_expiration(struct kvm_lapic *apic)
{
struct kvm_timer *ktimer = &apic->lapic_timer;
ktime_t now = ktime_get();
u64 tscl = rdtsc();
ktime_t delta;
/*
* Use kernel time as the time source for both the hrtimer deadline and
* TSC-based deadline so that they stay synchronized. Computing each
* deadline independently will cause the two deadlines to drift apart
* over time as differences in the periods accumulate, e.g. due to
* differences in the underlying clocks or numerical approximation errors.
*/
ktimer->target_expiration = ktime_add_ns(ktimer->target_expiration,
ktimer->period);
/*
* If the new expiration is in the past, e.g. because userspace stopped
* running the VM for an extended duration, then force the expiration
* to "now" and don't try to play catch-up with the missed events. KVM
* will only deliver a single interrupt regardless of how many events
* are pending, i.e. restarting the timer with an expiration in the
* past will do nothing more than waste host cycles, and can even lead
* to a hard lockup in extreme cases.
*/
if (ktime_before(ktimer->target_expiration, now))
ktimer->target_expiration = now;
/*
* Note, ensuring the expiration isn't in the past also prevents delta
* from going negative, which could cause the TSC deadline to become
* excessively large due to it an unsigned value.
*/
delta = ktime_sub(ktimer->target_expiration, now);
ktimer->tscdeadline = kvm_read_l1_tsc(apic->vcpu, tscl) +
nsec_to_cycles(apic->vcpu, delta);
}
static void start_sw_period(struct kvm_lapic *apic)
{
if (!apic->lapic_timer.period)
return;
if (ktime_after(ktime_get(),
apic->lapic_timer.target_expiration)) {
apic_timer_expired(apic, false);
if (apic_lvtt_oneshot(apic))
return;
advance_periodic_target_expiration(apic);
}
hrtimer_start(&apic->lapic_timer.timer,
apic->lapic_timer.target_expiration,
HRTIMER_MODE_ABS_HARD);
}
bool kvm_lapic_hv_timer_in_use(struct kvm_vcpu *vcpu)
{
if (!lapic_in_kernel(vcpu))
return false;
return vcpu->arch.apic->lapic_timer.hv_timer_in_use;
}
static void cancel_hv_timer(struct kvm_lapic *apic)
{
WARN_ON(preemptible());
WARN_ON(!apic->lapic_timer.hv_timer_in_use);
kvm_x86_call(cancel_hv_timer)(apic->vcpu);
apic->lapic_timer.hv_timer_in_use = false;
}
static bool start_hv_timer(struct kvm_lapic *apic)
{
struct kvm_timer *ktimer = &apic->lapic_timer;
struct kvm_vcpu *vcpu = apic->vcpu;
bool expired;
WARN_ON(preemptible());
if (!kvm_can_use_hv_timer(vcpu))
return false;
if (!ktimer->tscdeadline)
return false;
if (kvm_x86_call(set_hv_timer)(vcpu, ktimer->tscdeadline, &expired))
return false;
ktimer->hv_timer_in_use = true;
hrtimer_cancel(&ktimer->timer);
/*
* To simplify handling the periodic timer, leave the hv timer running
* even if the deadline timer has expired, i.e. rely on the resulting
* VM-Exit to recompute the periodic timer's target expiration.
*/
if (!apic_lvtt_period(apic)) {
/*
* Cancel the hv timer if the sw timer fired while the hv timer
* was being programmed, or if the hv timer itself expired.
*/
if (atomic_read(&ktimer->pending)) {
cancel_hv_timer(apic);
} else if (expired) {
apic_timer_expired(apic, false);
cancel_hv_timer(apic);
}
}
trace_kvm_hv_timer_state(vcpu->vcpu_id, ktimer->hv_timer_in_use);
return true;
}
static void start_sw_timer(struct kvm_lapic *apic)
{
struct kvm_timer *ktimer = &apic->lapic_timer;
WARN_ON(preemptible());
if (apic->lapic_timer.hv_timer_in_use)
cancel_hv_timer(apic);
if (!apic_lvtt_period(apic) && atomic_read(&ktimer->pending))
return;
if (apic_lvtt_period(apic) || apic_lvtt_oneshot(apic))
start_sw_period(apic);
else if (apic_lvtt_tscdeadline(apic))
start_sw_tscdeadline(apic);
trace_kvm_hv_timer_state(apic->vcpu->vcpu_id, false);
}
static void restart_apic_timer(struct kvm_lapic *apic)
{
preempt_disable();
if (!apic_lvtt_period(apic) && atomic_read(&apic->lapic_timer.pending))
goto out;
if (!start_hv_timer(apic))
start_sw_timer(apic);
out:
preempt_enable();
}
void kvm_lapic_expired_hv_timer(struct kvm_vcpu *vcpu)
{
struct kvm_lapic *apic = vcpu->arch.apic;
preempt_disable();
/* If the preempt notifier has already run, it also called apic_timer_expired */
if (!apic->lapic_timer.hv_timer_in_use)
goto out;
WARN_ON(kvm_vcpu_is_blocking(vcpu));
apic_timer_expired(apic, false);
cancel_hv_timer(apic);
if (apic_lvtt_period(apic) && apic->lapic_timer.period) {
advance_periodic_target_expiration(apic);
restart_apic_timer(apic);
}
out:
preempt_enable();
}
EXPORT_SYMBOL_FOR_KVM_INTERNAL(kvm_lapic_expired_hv_timer);
void kvm_lapic_switch_to_hv_timer(struct kvm_vcpu *vcpu)
{
restart_apic_timer(vcpu->arch.apic);
}
void kvm_lapic_switch_to_sw_timer(struct kvm_vcpu *vcpu)
{
struct kvm_lapic *apic = vcpu->arch.apic;
preempt_disable();
/* Possibly the TSC deadline timer is not enabled yet */
if (apic->lapic_timer.hv_timer_in_use)
start_sw_timer(apic);
preempt_enable();
}
void kvm_lapic_restart_hv_timer(struct kvm_vcpu *vcpu)
{
struct kvm_lapic *apic = vcpu->arch.apic;
WARN_ON(!apic->lapic_timer.hv_timer_in_use);
restart_apic_timer(apic);
}
static void __start_apic_timer(struct kvm_lapic *apic, u32 count_reg)
{
atomic_set(&apic->lapic_timer.pending, 0);
if ((apic_lvtt_period(apic) || apic_lvtt_oneshot(apic))
&& !set_target_expiration(apic, count_reg))
return;
restart_apic_timer(apic);
}
static void start_apic_timer(struct kvm_lapic *apic)
{
__start_apic_timer(apic, APIC_TMICT);
}
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) {
atomic_inc(&apic->vcpu->kvm->arch.vapics_in_nmi_mode);
} else
atomic_dec(&apic->vcpu->kvm->arch.vapics_in_nmi_mode);
}
}
static int get_lvt_index(u32 reg)
{
if (reg == APIC_LVTCMCI)
return LVT_CMCI;
if (reg < APIC_LVTT || reg > APIC_LVTERR)
return -1;
return array_index_nospec(
(reg - APIC_LVTT) >> 4, KVM_APIC_MAX_NR_LVT_ENTRIES);
}
static 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_xapic_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_apic_set_dfr(apic, val | 0x0FFFFFFF);
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;
for (i = 0; i < apic->nr_lvt_entries; i++) {
kvm_lapic_set_reg(apic, APIC_LVTx(i),
kvm_lapic_get_reg(apic, APIC_LVTx(i)) | APIC_LVT_MASKED);
}
apic_update_lvtt(apic);
atomic_set(&apic->lapic_timer.pending, 0);
}
break;
}
case APIC_ICR:
WARN_ON_ONCE(apic_x2apic_mode(apic));
/* No delay here, so we always clear the pending bit */
val &= ~APIC_ICR_BUSY;
kvm_apic_send_ipi(apic, val, kvm_lapic_get_reg(apic, APIC_ICR2));
kvm_lapic_set_reg(apic, APIC_ICR, val);
break;
case APIC_ICR2:
if (apic_x2apic_mode(apic))
ret = 1;
else
kvm_lapic_set_reg(apic, APIC_ICR2, val & 0xff000000);
break;
case APIC_LVT0:
apic_manage_nmi_watchdog(apic, val);
fallthrough;
case APIC_LVTTHMR:
case APIC_LVTPC:
case APIC_LVT1:
case APIC_LVTERR:
case APIC_LVTCMCI: {
u32 index = get_lvt_index(reg);
if (!kvm_lapic_lvt_supported(apic, index)) {
ret = 1;
break;
}
if (!kvm_apic_sw_enabled(apic))
val |= APIC_LVT_MASKED;
val &= apic_lvt_mask[index];
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[LVT_TIMER] | 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;
cancel_apic_timer(apic);
kvm_lapic_set_reg(apic, APIC_TMICT, val);
start_apic_timer(apic);
break;
case APIC_TDCR: {
uint32_t old_divisor = apic->divide_count;
kvm_lapic_set_reg(apic, APIC_TDCR, val & 0xb);
update_divide_count(apic);
if (apic->divide_count != old_divisor &&
apic->lapic_timer.period) {
hrtimer_cancel(&apic->lapic_timer.timer);
update_target_expiration(apic, old_divisor);
restart_apic_timer(apic);
}
break;
}
case APIC_ESR:
if (apic_x2apic_mode(apic) && val != 0)
ret = 1;
break;
case APIC_SELF_IPI:
/*
* Self-IPI exists only when x2APIC is enabled. Bits 7:0 hold
* the vector, everything else is reserved.
*/
if (!apic_x2apic_mode(apic) || (val & ~APIC_VECTOR_MASK))
ret = 1;
else
kvm_apic_send_ipi(apic, APIC_DEST_SELF | val, 0);
break;
default:
ret = 1;
break;
}
/*
* Recalculate APIC maps if necessary, e.g. if the software enable bit
* was toggled, the APIC ID changed, etc... The maps are marked dirty
* on relevant changes, i.e. this is a nop for most writes.
*/
kvm_recalculate_apic_map(apic->vcpu->kvm);
return ret;
}
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;
if (!kvm_apic_hw_enabled(apic) || apic_x2apic_mode(apic)) {
if (!kvm_check_has_quirk(vcpu->kvm,
KVM_X86_QUIRK_LAPIC_MMIO_HOLE))
return -EOPNOTSUPP;
return 0;
}
/*
* APIC register must be aligned on 128-bits boundary.
* 32/64/128 bits registers must be accessed thru 32 bits.
* Refer SDM 8.4.1
*/
if (len != 4 || (offset & 0xf))
return 0;
val = *(u32*)data;
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_FOR_KVM_INTERNAL(kvm_lapic_set_eoi);
#define X2APIC_ICR_RESERVED_BITS (GENMASK_ULL(31, 20) | GENMASK_ULL(17, 16) | BIT(13))
static int __kvm_x2apic_icr_write(struct kvm_lapic *apic, u64 data, bool fast)
{
if (data & X2APIC_ICR_RESERVED_BITS)
return 1;
/*
* The BUSY bit is reserved on both Intel and AMD in x2APIC mode, but
* only AMD requires it to be zero, Intel essentially just ignores the
* bit. And if IPI virtualization (Intel) or x2AVIC (AMD) is enabled,
* the CPU performs the reserved bits checks, i.e. the underlying CPU
* behavior will "win". Arbitrarily clear the BUSY bit, as there is no
* sane way to provide consistent behavior with respect to hardware.
*/
data &= ~APIC_ICR_BUSY;
if (fast) {
struct kvm_lapic_irq irq;
int ignored;
kvm_icr_to_lapic_irq(apic, (u32)data, (u32)(data >> 32), &irq);
if (!kvm_irq_delivery_to_apic_fast(apic->vcpu->kvm, apic, &irq,
&ignored))
return -EWOULDBLOCK;
trace_kvm_apic_ipi((u32)data, irq.dest_id);
} else {
kvm_apic_send_ipi(apic, (u32)data, (u32)(data >> 32));
}
if (kvm_x86_ops.x2apic_icr_is_split) {
kvm_lapic_set_reg(apic, APIC_ICR, data);
kvm_lapic_set_reg(apic, APIC_ICR2, data >> 32);
} else {
kvm_lapic_set_reg64(apic, APIC_ICR, data);
}
trace_kvm_apic_write(APIC_ICR, data);
return 0;
}
static int kvm_x2apic_icr_write(struct kvm_lapic *apic, u64 data)
{
return __kvm_x2apic_icr_write(apic, data, false);
}
int kvm_x2apic_icr_write_fast(struct kvm_lapic *apic, u64 data)
{
return __kvm_x2apic_icr_write(apic, data, true);
}
static u64 kvm_x2apic_icr_read(struct kvm_lapic *apic)
{
if (kvm_x86_ops.x2apic_icr_is_split)
return (u64)kvm_lapic_get_reg(apic, APIC_ICR) |
(u64)kvm_lapic_get_reg(apic, APIC_ICR2) << 32;
return kvm_lapic_get_reg64(apic, APIC_ICR);
}
/* emulate APIC access in a trap manner */
void kvm_apic_write_nodecode(struct kvm_vcpu *vcpu, u32 offset)
{
struct kvm_lapic *apic = vcpu->arch.apic;
if (KVM_BUG_ON(!lapic_in_kernel(vcpu), vcpu->kvm))
return;
/*
* ICR is a single 64-bit register when x2APIC is enabled, all others
* registers hold 32-bit values. For legacy xAPIC, ICR writes need to
* go down the common path to get the upper half from ICR2.
*
* Note, using the write helpers may incur an unnecessary write to the
* virtual APIC state, but KVM needs to conditionally modify the value
* in certain cases, e.g. to clear the ICR busy bit. The cost of extra
* conditional branches is likely a wash relative to the cost of the
* maybe-unecessary write, and both are in the noise anyways.
*/
if (apic_x2apic_mode(apic) && offset == APIC_ICR)
WARN_ON_ONCE(kvm_x2apic_icr_write(apic, kvm_x2apic_icr_read(apic)));
else
kvm_lapic_reg_write(apic, offset, kvm_lapic_get_reg(apic, offset));
}
EXPORT_SYMBOL_FOR_KVM_INTERNAL(kvm_apic_write_nodecode);
void kvm_free_lapic(struct kvm_vcpu *vcpu)
{
struct kvm_lapic *apic = vcpu->arch.apic;
if (!vcpu->arch.apic) {
static_branch_dec(&kvm_has_noapic_vcpu);
return;
}
hrtimer_cancel(&apic->lapic_timer.timer);
if (!(vcpu->arch.apic_base & MSR_IA32_APICBASE_ENABLE))
static_branch_slow_dec_deferred(&apic_hw_disabled);
if (!apic->sw_enabled)
static_branch_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_apic_present(vcpu) || !apic_lvtt_tscdeadline(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_apic_present(vcpu) || !apic_lvtt_tscdeadline(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)
{
apic_set_tpr(vcpu->arch.apic, (cr8 & 0x0f) << 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_update_cr8_intercept(struct kvm_vcpu *vcpu)
{
int max_irr, tpr;
if (!kvm_x86_ops.update_cr8_intercept)
return;
if (!lapic_in_kernel(vcpu))
return;
if (vcpu->arch.apic->apicv_active)
return;
if (!vcpu->arch.apic->vapic_addr)
max_irr = kvm_lapic_find_highest_irr(vcpu);
else
max_irr = -1;
if (max_irr != -1)
max_irr >>= 4;
tpr = kvm_lapic_get_cr8(vcpu);
kvm_x86_call(update_cr8_intercept)(vcpu, tpr, max_irr);
}
static void __kvm_apic_set_base(struct kvm_vcpu *vcpu, u64 value)
{
u64 old_value = vcpu->arch.apic_base;
struct kvm_lapic *apic = vcpu->arch.apic;
vcpu->arch.apic_base = value;
if ((old_value ^ value) & MSR_IA32_APICBASE_ENABLE)
vcpu->arch.cpuid_dynamic_bits_dirty = true;
if (!apic)
return;
/* update jump label if enable bit changes */
if ((old_value ^ value) & MSR_IA32_APICBASE_ENABLE) {
if (value & MSR_IA32_APICBASE_ENABLE) {
kvm_apic_set_xapic_id(apic, vcpu->vcpu_id);
static_branch_slow_dec_deferred(&apic_hw_disabled);
/* Check if there are APF page ready requests pending */
kvm_make_request(KVM_REQ_APF_READY, vcpu);
} else {
static_branch_inc(&apic_hw_disabled.key);
atomic_set_release(&apic->vcpu->kvm->arch.apic_map_dirty, DIRTY);
}
}
if ((old_value ^ value) & X2APIC_ENABLE) {
if (value & X2APIC_ENABLE)
kvm_apic_set_x2apic_id(apic, vcpu->vcpu_id);
else if (value & MSR_IA32_APICBASE_ENABLE)
kvm_apic_set_xapic_id(apic, vcpu->vcpu_id);
}
if ((old_value ^ value) & (MSR_IA32_APICBASE_ENABLE | X2APIC_ENABLE)) {
kvm_make_request(KVM_REQ_APICV_UPDATE, vcpu);
kvm_x86_call(set_virtual_apic_mode)(vcpu);
}
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) {
kvm_set_apicv_inhibit(apic->vcpu->kvm,
APICV_INHIBIT_REASON_APIC_BASE_MODIFIED);
}
}
int kvm_apic_set_base(struct kvm_vcpu *vcpu, u64 value, bool host_initiated)
{
enum lapic_mode old_mode = kvm_get_apic_mode(vcpu);
enum lapic_mode new_mode = kvm_apic_mode(value);
if (vcpu->arch.apic_base == value)
return 0;
u64 reserved_bits = kvm_vcpu_reserved_gpa_bits_raw(vcpu) | 0x2ff |
(guest_cpu_cap_has(vcpu, X86_FEATURE_X2APIC) ? 0 : X2APIC_ENABLE);
if ((value & reserved_bits) != 0 || new_mode == LAPIC_MODE_INVALID)
return 1;
if (!host_initiated) {
if (old_mode == LAPIC_MODE_X2APIC && new_mode == LAPIC_MODE_XAPIC)
return 1;
if (old_mode == LAPIC_MODE_DISABLED && new_mode == LAPIC_MODE_X2APIC)
return 1;
}
__kvm_apic_set_base(vcpu, value);
kvm_recalculate_apic_map(vcpu->kvm);
return 0;
}
EXPORT_SYMBOL_FOR_KVM_INTERNAL(kvm_apic_set_base);
void kvm_apic_update_apicv(struct kvm_vcpu *vcpu)
{
struct kvm_lapic *apic = vcpu->arch.apic;
/*
* When APICv is enabled, KVM must always search the IRR for a pending
* IRQ, as other vCPUs and devices can set IRR bits even if the vCPU
* isn't running. If APICv is disabled, KVM _should_ search the IRR
* for a pending IRQ. But KVM currently doesn't ensure *all* hardware,
* e.g. CPUs and IOMMUs, has seen the change in state, i.e. searching
* the IRR at this time could race with IRQ delivery from hardware that
* still sees APICv as being enabled.
*
* FIXME: Ensure other vCPUs and devices observe the change in APICv
* state prior to updating KVM's metadata caches, so that KVM
* can safely search the IRR and set irr_pending accordingly.
*/
apic->irr_pending = true;
/*
* Update SVI when APICv gets enabled, otherwise SVI won't reflect the
* highest bit in vISR and the next accelerated EOI in the guest won't
* be virtualized correctly (the CPU uses SVI to determine which vISR
* vector to clear).
*/
if (apic->apicv_active) {
apic->isr_count = 1;
kvm_x86_call(hwapic_isr_update)(vcpu, apic_find_highest_isr(apic));
} else {
apic->isr_count = count_vectors(apic->regs + APIC_ISR);
}
apic->highest_isr_cache = -1;
}
int kvm_alloc_apic_access_page(struct kvm *kvm)
{
void __user *hva;
guard(mutex)(&kvm->slots_lock);
if (kvm->arch.apic_access_memslot_enabled ||
kvm->arch.apic_access_memslot_inhibited)
return 0;
hva = __x86_set_memory_region(kvm, APIC_ACCESS_PAGE_PRIVATE_MEMSLOT,
APIC_DEFAULT_PHYS_BASE, PAGE_SIZE);
if (IS_ERR(hva))
return PTR_ERR(hva);
kvm->arch.apic_access_memslot_enabled = true;
return 0;
}
EXPORT_SYMBOL_FOR_KVM_INTERNAL(kvm_alloc_apic_access_page);
void kvm_inhibit_apic_access_page(struct kvm_vcpu *vcpu)
{
struct kvm *kvm = vcpu->kvm;
if (!kvm->arch.apic_access_memslot_enabled)
return;
kvm_vcpu_srcu_read_unlock(vcpu);
mutex_lock(&kvm->slots_lock);
if (kvm->arch.apic_access_memslot_enabled) {
__x86_set_memory_region(kvm, APIC_ACCESS_PAGE_PRIVATE_MEMSLOT, 0, 0);
/*
* Clear "enabled" after the memslot is deleted so that a
* different vCPU doesn't get a false negative when checking
* the flag out of slots_lock. No additional memory barrier is
* needed as modifying memslots requires waiting other vCPUs to
* drop SRCU (see above), and false positives are ok as the
* flag is rechecked after acquiring slots_lock.
*/
kvm->arch.apic_access_memslot_enabled = false;
/*
* Mark the memslot as inhibited to prevent reallocating the
* memslot during vCPU creation, e.g. if a vCPU is hotplugged.
*/
kvm->arch.apic_access_memslot_inhibited = true;
}
mutex_unlock(&kvm->slots_lock);
kvm_vcpu_srcu_read_lock(vcpu);
}
void kvm_lapic_reset(struct kvm_vcpu *vcpu, bool init_event)
{
struct kvm_lapic *apic = vcpu->arch.apic;
u64 msr_val;
int i;
kvm_x86_call(apicv_pre_state_restore)(vcpu);
if (!init_event) {
msr_val = APIC_DEFAULT_PHYS_BASE | MSR_IA32_APICBASE_ENABLE;
if (kvm_vcpu_is_reset_bsp(vcpu))
msr_val |= MSR_IA32_APICBASE_BSP;
/*
* Use the inner helper to avoid an extra recalcuation of the
* optimized APIC map if some other task has dirtied the map.
* The recalculation needed for this vCPU will be done after
* all APIC state has been initialized (see below).
*/
__kvm_apic_set_base(vcpu, msr_val);
}
if (!apic)
return;
/* Stop the timer in case it's a reset to an active apic */
hrtimer_cancel(&apic->lapic_timer.timer);
/* The xAPIC ID is set at RESET even if the APIC was already enabled. */
if (!init_event)
kvm_apic_set_xapic_id(apic, vcpu->vcpu_id);
kvm_apic_set_version(apic->vcpu);
for (i = 0; i < apic->nr_lvt_entries; i++)
kvm_lapic_set_reg(apic, APIC_LVTx(i), APIC_LVT_MASKED);
apic_update_lvtt(apic);
if (kvm_vcpu_is_reset_bsp(vcpu) &&
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_apic_set_dfr(apic, 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);
if (!apic_x2apic_mode(apic)) {
kvm_lapic_set_reg(apic, APIC_ICR, 0);
kvm_lapic_set_reg(apic, APIC_ICR2, 0);
} else {
kvm_lapic_set_reg64(apic, APIC_ICR, 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);
}
kvm_apic_update_apicv(vcpu);
update_divide_count(apic);
atomic_set(&apic->lapic_timer.pending, 0);
vcpu->arch.pv_eoi.msr_val = 0;
apic_update_ppr(apic);
if (apic->apicv_active)
kvm_x86_call(apicv_post_state_restore)(vcpu);
vcpu->arch.apic_arb_prio = 0;
vcpu->arch.apic_attention = 0;
kvm_recalculate_apic_map(vcpu->kvm);
}
/*
*----------------------------------------------------------------------
* 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;
int r;
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;
r = __apic_accept_irq(apic, mode, vector, 1, trig_mode, NULL);
if (r && lvt_type == APIC_LVTPC &&
guest_cpuid_is_intel_compatible(apic->vcpu))
kvm_lapic_set_reg(apic, APIC_LVTPC, reg | APIC_LVT_MASKED);
return r;
}
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, true);
if (lapic_is_periodic(apic) && !WARN_ON_ONCE(!apic->lapic_timer.period)) {
advance_periodic_target_expiration(apic);
hrtimer_set_expires(&ktimer->timer, ktimer->target_expiration);
return HRTIMER_RESTART;
} else
return HRTIMER_NORESTART;
}
int kvm_create_lapic(struct kvm_vcpu *vcpu)
{
struct kvm_lapic *apic;
if (!irqchip_in_kernel(vcpu->kvm)) {
static_branch_inc(&kvm_has_noapic_vcpu);
return 0;
}
apic = kzalloc_obj(*apic, GFP_KERNEL_ACCOUNT);
if (!apic)
goto nomem;
vcpu->arch.apic = apic;
if (kvm_x86_ops.alloc_apic_backing_page)
apic->regs = kvm_x86_call(alloc_apic_backing_page)(vcpu);
else
apic->regs = (void *)get_zeroed_page(GFP_KERNEL_ACCOUNT);
if (!apic->regs) {
printk(KERN_ERR "malloc apic regs error for vcpu %x\n",
vcpu->vcpu_id);
goto nomem_free_apic;
}
apic->vcpu = vcpu;
apic->nr_lvt_entries = kvm_apic_calc_nr_lvt_entries(vcpu);
hrtimer_setup(&apic->lapic_timer.timer, apic_timer_fn, CLOCK_MONOTONIC,
HRTIMER_MODE_ABS_HARD);
if (lapic_timer_advance)
apic->lapic_timer.timer_advance_ns = LAPIC_TIMER_ADVANCE_NS_INIT;
/*
* Stuff the APIC ENABLE bit in lieu of temporarily incrementing
* apic_hw_disabled; the full RESET value is set by kvm_lapic_reset().
*/
vcpu->arch.apic_base = MSR_IA32_APICBASE_ENABLE;
static_branch_inc(&apic_sw_disabled.key); /* sw disabled at reset */
kvm_iodevice_init(&apic->dev, &apic_mmio_ops);
/*
* Defer evaluating inhibits until the vCPU is first run, as this vCPU
* will not get notified of any changes until this vCPU is visible to
* other vCPUs (marked online and added to the set of vCPUs).
*
* Opportunistically mark APICv active as VMX in particularly is highly
* unlikely to have inhibits. Ignore the current per-VM APICv state so
* that vCPU creation is guaranteed to run with a deterministic value,
* the request will ensure the vCPU gets the correct state before VM-Entry.
*/
if (enable_apicv) {
apic->apicv_active = true;
kvm_make_request(KVM_REQ_APICV_UPDATE, vcpu);
}
return 0;
nomem_free_apic:
kfree(apic);
vcpu->arch.apic = NULL;
nomem:
return -ENOMEM;
}
int kvm_apic_has_interrupt(struct kvm_vcpu *vcpu)
{
struct kvm_lapic *apic = vcpu->arch.apic;
u32 ppr;
if (!kvm_apic_present(vcpu))
return -1;
if (apic->guest_apic_protected)
return -1;
__apic_update_ppr(apic, &ppr);
return apic_has_interrupt_for_ppr(apic, ppr);
}
EXPORT_SYMBOL_FOR_KVM_INTERNAL(kvm_apic_has_interrupt);
int kvm_apic_accept_pic_intr(struct kvm_vcpu *vcpu)
{
u32 lvt0 = kvm_lapic_get_reg(vcpu->arch.apic, APIC_LVT0);
if (!kvm_apic_hw_enabled(vcpu->arch.apic))
return 1;
if ((lvt0 & APIC_LVT_MASKED) == 0 &&
GET_APIC_DELIVERY_MODE(lvt0) == APIC_MODE_EXTINT)
return 1;
return 0;
}
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_inject_pending_timer_irqs(apic);
atomic_set(&apic->lapic_timer.pending, 0);
}
}
void kvm_apic_ack_interrupt(struct kvm_vcpu *vcpu, int vector)
{
struct kvm_lapic *apic = vcpu->arch.apic;
u32 ppr;
if (WARN_ON_ONCE(vector < 0 || !apic))
return;
/*
* 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_clear_irr(vector, apic);
if (kvm_hv_synic_auto_eoi_set(vcpu, vector)) {
/*
* For auto-EOI interrupts, there might be another pending
* interrupt above PPR, so check whether to raise another
* KVM_REQ_EVENT.
*/
apic_update_ppr(apic);
} else {
/*
* For normal interrupts, PPR has been raised and there cannot
* be a higher-priority pending interrupt---except if there was
* a concurrent interrupt injection, but that would have
* triggered KVM_REQ_EVENT already.
*/
apic_set_isr(vector, apic);
__apic_update_ppr(apic, &ppr);
}
}
EXPORT_SYMBOL_FOR_KVM_INTERNAL(kvm_apic_ack_interrupt);
static int kvm_apic_state_fixup(struct kvm_vcpu *vcpu,
struct kvm_lapic_state *s, bool set)
{
if (apic_x2apic_mode(vcpu->arch.apic)) {
u32 x2apic_id = kvm_x2apic_id(vcpu->arch.apic);
u32 *id = (u32 *)(s->regs + APIC_ID);
u32 *ldr = (u32 *)(s->regs + APIC_LDR);
u64 icr;
if (vcpu->kvm->arch.x2apic_format) {
if (*id != x2apic_id)
return -EINVAL;
} else {
/*
* Ignore the userspace value when setting APIC state.
* KVM's model is that the x2APIC ID is readonly, e.g.
* KVM only supports delivering interrupts to KVM's
* version of the x2APIC ID. However, for backwards
* compatibility, don't reject attempts to set a
* mismatched ID for userspace that hasn't opted into
* x2apic_format.
*/
if (set)
*id = x2apic_id;
else
*id = x2apic_id << 24;
}
/*
* In x2APIC mode, the LDR is fixed and based on the id. And
* if the ICR is _not_ split, ICR is internally a single 64-bit
* register, but needs to be split to ICR+ICR2 in userspace for
* backwards compatibility.
*/
if (set)
*ldr = kvm_apic_calc_x2apic_ldr(x2apic_id);
if (!kvm_x86_ops.x2apic_icr_is_split) {
if (set) {
icr = apic_get_reg(s->regs, APIC_ICR) |
(u64)apic_get_reg(s->regs, APIC_ICR2) << 32;
apic_set_reg64(s->regs, APIC_ICR, icr);
} else {
icr = apic_get_reg64(s->regs, APIC_ICR);
apic_set_reg(s->regs, APIC_ICR2, icr >> 32);
}
}
}
return 0;
}
int kvm_apic_get_state(struct kvm_vcpu *vcpu, struct kvm_lapic_state *s)
{
memcpy(s->regs, vcpu->arch.apic->regs, sizeof(*s));
/*
* Get calculated timer current count for remaining timer period (if
* any) and store it in the returned register set.
*/
apic_set_reg(s->regs, APIC_TMCCT, __apic_read(vcpu->arch.apic, APIC_TMCCT));
return kvm_apic_state_fixup(vcpu, s, false);
}
int kvm_apic_set_state(struct kvm_vcpu *vcpu, struct kvm_lapic_state *s)
{
struct kvm_lapic *apic = vcpu->arch.apic;
int r;
kvm_x86_call(apicv_pre_state_restore)(vcpu);
/* set SPIV separately to get count of SW disabled APICs right */
apic_set_spiv(apic, *((u32 *)(s->regs + APIC_SPIV)));
r = kvm_apic_state_fixup(vcpu, s, true);
if (r) {
kvm_recalculate_apic_map(vcpu->kvm);
return r;
}
memcpy(vcpu->arch.apic->regs, s->regs, sizeof(*s));
atomic_set_release(&apic->vcpu->kvm->arch.apic_map_dirty, DIRTY);
kvm_recalculate_apic_map(vcpu->kvm);
kvm_apic_set_version(vcpu);
apic_update_ppr(apic);
cancel_apic_timer(apic);
apic->lapic_timer.expired_tscdeadline = 0;
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_TMCCT);
kvm_lapic_set_reg(apic, APIC_TMCCT, 0);
kvm_apic_update_apicv(vcpu);
if (apic->apicv_active)
kvm_x86_call(apicv_post_state_restore)(vcpu);
kvm_make_request(KVM_REQ_EVENT, vcpu);
#ifdef CONFIG_KVM_IOAPIC
if (ioapic_in_kernel(vcpu->kvm))
kvm_rtc_eoi_tracking_restore_one(vcpu);
#endif
vcpu->arch.apic_arb_prio = 0;
return 0;
}
void __kvm_migrate_apic_timer(struct kvm_vcpu *vcpu)
{
struct hrtimer *timer;
if (!lapic_in_kernel(vcpu) ||
kvm_can_post_timer_interrupt(vcpu))
return;
timer = &vcpu->arch.apic->lapic_timer.timer;
if (hrtimer_cancel(timer))
hrtimer_start_expires(timer, HRTIMER_MODE_ABS_HARD);
}
/*
* 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)
{
int vector;
if (unlikely(!pv_eoi_enabled(vcpu))) {
__clear_bit(KVM_APIC_PV_EOI_PENDING, &vcpu->arch.apic_attention);
return;
}
/*
* 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.
*/
if (pv_eoi_test_and_clr_pending(vcpu))
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;
}
static int kvm_lapic_msr_read(struct kvm_lapic *apic, u32 reg, u64 *data)
{
u32 low;
if (reg == APIC_ICR) {
*data = kvm_x2apic_icr_read(apic);
return 0;
}
if (kvm_lapic_reg_read(apic, reg, 4, &low))
return 1;
*data = low;
return 0;
}
static int kvm_lapic_msr_write(struct kvm_lapic *apic, u32 reg, u64 data)
{
/*
* ICR is a 64-bit register in x2APIC mode (and Hyper-V PV vAPIC) and
* can be written as such, all other registers remain accessible only
* through 32-bit reads/writes.
*/
if (reg == APIC_ICR)
return kvm_x2apic_icr_write(apic, data);
/* Bits 63:32 are reserved in all other registers. */
if (data >> 32)
return 1;
return kvm_lapic_reg_write(apic, reg, (u32)data);
}
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;
return kvm_lapic_msr_write(apic, reg, 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;
if (!lapic_in_kernel(vcpu) || !apic_x2apic_mode(apic))
return 1;
return kvm_lapic_msr_read(apic, reg, data);
}
int kvm_hv_vapic_msr_write(struct kvm_vcpu *vcpu, u32 reg, u64 data)
{
if (!lapic_in_kernel(vcpu))
return 1;
return kvm_lapic_msr_write(vcpu->arch.apic, reg, data);
}
int kvm_hv_vapic_msr_read(struct kvm_vcpu *vcpu, u32 reg, u64 *data)
{
if (!lapic_in_kernel(vcpu))
return 1;
return kvm_lapic_msr_read(vcpu->arch.apic, reg, data);
}
int kvm_lapic_set_pv_eoi(struct kvm_vcpu *vcpu, u64 data, unsigned long len)
{
u64 addr = data & ~KVM_MSR_ENABLED;
struct gfn_to_hva_cache *ghc = &vcpu->arch.pv_eoi.data;
unsigned long new_len;
int ret;
if (!IS_ALIGNED(addr, 4))
return 1;
if (data & KVM_MSR_ENABLED) {
if (addr == ghc->gpa && len <= ghc->len)
new_len = ghc->len;
else
new_len = len;
ret = kvm_gfn_to_hva_cache_init(vcpu->kvm, ghc, addr, new_len);
if (ret)
return ret;
}
vcpu->arch.pv_eoi.msr_val = data;
return 0;
}
int kvm_apic_accept_events(struct kvm_vcpu *vcpu)
{
struct kvm_lapic *apic = vcpu->arch.apic;
u8 sipi_vector;
int r;
if (!kvm_apic_has_pending_init_or_sipi(vcpu))
return 0;
if (is_guest_mode(vcpu)) {
r = kvm_check_nested_events(vcpu);
if (r < 0)
return r == -EBUSY ? 0 : r;
/*
* Continue processing INIT/SIPI even if a nested VM-Exit
* occurred, e.g. pending SIPIs should be dropped if INIT+SIPI
* are blocked as a result of transitioning to VMX root mode.
*/
}
/*
* INITs are blocked while CPU is in specific states (SMM, VMX root
* mode, SVM with GIF=0), while SIPIs are dropped if the CPU isn't in
* wait-for-SIPI (WFS).
*/
if (!kvm_apic_init_sipi_allowed(vcpu)) {
clear_bit(KVM_APIC_SIPI, &apic->pending_events);
return 0;
}
if (test_and_clear_bit(KVM_APIC_INIT, &apic->pending_events)) {
kvm_vcpu_reset(vcpu, true);
if (kvm_vcpu_is_bsp(apic->vcpu))
kvm_set_mp_state(vcpu, KVM_MP_STATE_RUNNABLE);
else
kvm_set_mp_state(vcpu, KVM_MP_STATE_INIT_RECEIVED);
}
if (test_and_clear_bit(KVM_APIC_SIPI, &apic->pending_events)) {
if (vcpu->arch.mp_state == KVM_MP_STATE_INIT_RECEIVED) {
/* evaluate pending_events before reading the vector */
smp_rmb();
sipi_vector = apic->sipi_vector;
kvm_x86_call(vcpu_deliver_sipi_vector)(vcpu,
sipi_vector);
kvm_set_mp_state(vcpu, KVM_MP_STATE_RUNNABLE);
}
}
return 0;
}
void kvm_lapic_exit(void)
{
static_key_deferred_flush(&apic_hw_disabled);
WARN_ON(static_branch_unlikely(&apic_hw_disabled.key));
static_key_deferred_flush(&apic_sw_disabled);
WARN_ON(static_branch_unlikely(&apic_sw_disabled.key));
}