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arm.c
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arm.c
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// SPDX-License-Identifier: GPL-2.0-only
/*
* Copyright (C) 2012 - Virtual Open Systems and Columbia University
* Author: Christoffer Dall <c.dall@virtualopensystems.com>
*/
#include <linux/bug.h>
#include <linux/cpu_pm.h>
#include <linux/errno.h>
#include <linux/err.h>
#include <linux/kvm_host.h>
#include <linux/list.h>
#include <linux/module.h>
#include <linux/vmalloc.h>
#include <linux/fs.h>
#include <linux/mman.h>
#include <linux/sched.h>
#include <linux/kmemleak.h>
#include <linux/kvm.h>
#include <linux/kvm_irqfd.h>
#include <linux/irqbypass.h>
#include <linux/sched/stat.h>
#include <linux/psci.h>
#include <trace/events/kvm.h>
#define CREATE_TRACE_POINTS
#include "trace_arm.h"
#include <linux/uaccess.h>
#include <asm/ptrace.h>
#include <asm/mman.h>
#include <asm/tlbflush.h>
#include <asm/cacheflush.h>
#include <asm/cpufeature.h>
#include <asm/virt.h>
#include <asm/kvm_arm.h>
#include <asm/kvm_asm.h>
#include <asm/kvm_mmu.h>
#include <asm/kvm_emulate.h>
#include <asm/sections.h>
#include <kvm/arm_hypercalls.h>
#include <kvm/arm_pmu.h>
#include <kvm/arm_psci.h>
#ifdef REQUIRES_VIRT
__asm__(".arch_extension virt");
#endif
static enum kvm_mode kvm_mode = KVM_MODE_DEFAULT;
DEFINE_STATIC_KEY_FALSE(kvm_protected_mode_initialized);
DECLARE_KVM_HYP_PER_CPU(unsigned long, kvm_hyp_vector);
static DEFINE_PER_CPU(unsigned long, kvm_arm_hyp_stack_page);
unsigned long kvm_arm_hyp_percpu_base[NR_CPUS];
DECLARE_KVM_NVHE_PER_CPU(struct kvm_nvhe_init_params, kvm_init_params);
/* The VMID used in the VTTBR */
static atomic64_t kvm_vmid_gen = ATOMIC64_INIT(1);
static u32 kvm_next_vmid;
static DEFINE_SPINLOCK(kvm_vmid_lock);
static bool vgic_present;
static DEFINE_PER_CPU(unsigned char, kvm_arm_hardware_enabled);
DEFINE_STATIC_KEY_FALSE(userspace_irqchip_in_use);
int kvm_arch_vcpu_should_kick(struct kvm_vcpu *vcpu)
{
return kvm_vcpu_exiting_guest_mode(vcpu) == IN_GUEST_MODE;
}
int kvm_arch_hardware_setup(void *opaque)
{
return 0;
}
int kvm_arch_check_processor_compat(void *opaque)
{
return 0;
}
int kvm_vm_ioctl_enable_cap(struct kvm *kvm,
struct kvm_enable_cap *cap)
{
int r;
if (cap->flags)
return -EINVAL;
switch (cap->cap) {
case KVM_CAP_ARM_NISV_TO_USER:
r = 0;
kvm->arch.return_nisv_io_abort_to_user = true;
break;
case KVM_CAP_ARM_MTE:
mutex_lock(&kvm->lock);
if (!system_supports_mte() || kvm->created_vcpus) {
r = -EINVAL;
} else {
r = 0;
kvm->arch.mte_enabled = true;
}
mutex_unlock(&kvm->lock);
break;
default:
r = -EINVAL;
break;
}
return r;
}
static int kvm_arm_default_max_vcpus(void)
{
return vgic_present ? kvm_vgic_get_max_vcpus() : KVM_MAX_VCPUS;
}
static void set_default_spectre(struct kvm *kvm)
{
/*
* The default is to expose CSV2 == 1 if the HW isn't affected.
* Although this is a per-CPU feature, we make it global because
* asymmetric systems are just a nuisance.
*
* Userspace can override this as long as it doesn't promise
* the impossible.
*/
if (arm64_get_spectre_v2_state() == SPECTRE_UNAFFECTED)
kvm->arch.pfr0_csv2 = 1;
if (arm64_get_meltdown_state() == SPECTRE_UNAFFECTED)
kvm->arch.pfr0_csv3 = 1;
}
/**
* kvm_arch_init_vm - initializes a VM data structure
* @kvm: pointer to the KVM struct
*/
int kvm_arch_init_vm(struct kvm *kvm, unsigned long type)
{
int ret;
ret = kvm_arm_setup_stage2(kvm, type);
if (ret)
return ret;
ret = kvm_init_stage2_mmu(kvm, &kvm->arch.mmu);
if (ret)
return ret;
ret = create_hyp_mappings(kvm, kvm + 1, PAGE_HYP);
if (ret)
goto out_free_stage2_pgd;
kvm_vgic_early_init(kvm);
/* The maximum number of VCPUs is limited by the host's GIC model */
kvm->arch.max_vcpus = kvm_arm_default_max_vcpus();
set_default_spectre(kvm);
return ret;
out_free_stage2_pgd:
kvm_free_stage2_pgd(&kvm->arch.mmu);
return ret;
}
vm_fault_t kvm_arch_vcpu_fault(struct kvm_vcpu *vcpu, struct vm_fault *vmf)
{
return VM_FAULT_SIGBUS;
}
/**
* kvm_arch_destroy_vm - destroy the VM data structure
* @kvm: pointer to the KVM struct
*/
void kvm_arch_destroy_vm(struct kvm *kvm)
{
int i;
bitmap_free(kvm->arch.pmu_filter);
kvm_vgic_destroy(kvm);
for (i = 0; i < KVM_MAX_VCPUS; ++i) {
if (kvm->vcpus[i]) {
kvm_vcpu_destroy(kvm->vcpus[i]);
kvm->vcpus[i] = NULL;
}
}
atomic_set(&kvm->online_vcpus, 0);
}
int kvm_vm_ioctl_check_extension(struct kvm *kvm, long ext)
{
int r;
switch (ext) {
case KVM_CAP_IRQCHIP:
r = vgic_present;
break;
case KVM_CAP_IOEVENTFD:
case KVM_CAP_DEVICE_CTRL:
case KVM_CAP_USER_MEMORY:
case KVM_CAP_SYNC_MMU:
case KVM_CAP_DESTROY_MEMORY_REGION_WORKS:
case KVM_CAP_ONE_REG:
case KVM_CAP_ARM_PSCI:
case KVM_CAP_ARM_PSCI_0_2:
case KVM_CAP_READONLY_MEM:
case KVM_CAP_MP_STATE:
case KVM_CAP_IMMEDIATE_EXIT:
case KVM_CAP_VCPU_EVENTS:
case KVM_CAP_ARM_IRQ_LINE_LAYOUT_2:
case KVM_CAP_ARM_NISV_TO_USER:
case KVM_CAP_ARM_INJECT_EXT_DABT:
case KVM_CAP_SET_GUEST_DEBUG:
case KVM_CAP_VCPU_ATTRIBUTES:
case KVM_CAP_PTP_KVM:
r = 1;
break;
case KVM_CAP_SET_GUEST_DEBUG2:
return KVM_GUESTDBG_VALID_MASK;
case KVM_CAP_ARM_SET_DEVICE_ADDR:
r = 1;
break;
case KVM_CAP_NR_VCPUS:
r = num_online_cpus();
break;
case KVM_CAP_MAX_VCPUS:
case KVM_CAP_MAX_VCPU_ID:
if (kvm)
r = kvm->arch.max_vcpus;
else
r = kvm_arm_default_max_vcpus();
break;
case KVM_CAP_MSI_DEVID:
if (!kvm)
r = -EINVAL;
else
r = kvm->arch.vgic.msis_require_devid;
break;
case KVM_CAP_ARM_USER_IRQ:
/*
* 1: EL1_VTIMER, EL1_PTIMER, and PMU.
* (bump this number if adding more devices)
*/
r = 1;
break;
case KVM_CAP_ARM_MTE:
r = system_supports_mte();
break;
case KVM_CAP_STEAL_TIME:
r = kvm_arm_pvtime_supported();
break;
case KVM_CAP_ARM_EL1_32BIT:
r = cpus_have_const_cap(ARM64_HAS_32BIT_EL1);
break;
case KVM_CAP_GUEST_DEBUG_HW_BPS:
r = get_num_brps();
break;
case KVM_CAP_GUEST_DEBUG_HW_WPS:
r = get_num_wrps();
break;
case KVM_CAP_ARM_PMU_V3:
r = kvm_arm_support_pmu_v3();
break;
case KVM_CAP_ARM_INJECT_SERROR_ESR:
r = cpus_have_const_cap(ARM64_HAS_RAS_EXTN);
break;
case KVM_CAP_ARM_VM_IPA_SIZE:
r = get_kvm_ipa_limit();
break;
case KVM_CAP_ARM_SVE:
r = system_supports_sve();
break;
case KVM_CAP_ARM_PTRAUTH_ADDRESS:
case KVM_CAP_ARM_PTRAUTH_GENERIC:
r = system_has_full_ptr_auth();
break;
default:
r = 0;
}
return r;
}
long kvm_arch_dev_ioctl(struct file *filp,
unsigned int ioctl, unsigned long arg)
{
return -EINVAL;
}
struct kvm *kvm_arch_alloc_vm(void)
{
if (!has_vhe())
return kzalloc(sizeof(struct kvm), GFP_KERNEL);
return vzalloc(sizeof(struct kvm));
}
void kvm_arch_free_vm(struct kvm *kvm)
{
if (!has_vhe())
kfree(kvm);
else
vfree(kvm);
}
int kvm_arch_vcpu_precreate(struct kvm *kvm, unsigned int id)
{
if (irqchip_in_kernel(kvm) && vgic_initialized(kvm))
return -EBUSY;
if (id >= kvm->arch.max_vcpus)
return -EINVAL;
return 0;
}
int kvm_arch_vcpu_create(struct kvm_vcpu *vcpu)
{
int err;
/* Force users to call KVM_ARM_VCPU_INIT */
vcpu->arch.target = -1;
bitmap_zero(vcpu->arch.features, KVM_VCPU_MAX_FEATURES);
vcpu->arch.mmu_page_cache.gfp_zero = __GFP_ZERO;
/* Set up the timer */
kvm_timer_vcpu_init(vcpu);
kvm_pmu_vcpu_init(vcpu);
kvm_arm_reset_debug_ptr(vcpu);
kvm_arm_pvtime_vcpu_init(&vcpu->arch);
vcpu->arch.hw_mmu = &vcpu->kvm->arch.mmu;
err = kvm_vgic_vcpu_init(vcpu);
if (err)
return err;
return create_hyp_mappings(vcpu, vcpu + 1, PAGE_HYP);
}
void kvm_arch_vcpu_postcreate(struct kvm_vcpu *vcpu)
{
}
void kvm_arch_vcpu_destroy(struct kvm_vcpu *vcpu)
{
if (vcpu->arch.has_run_once && unlikely(!irqchip_in_kernel(vcpu->kvm)))
static_branch_dec(&userspace_irqchip_in_use);
kvm_mmu_free_memory_cache(&vcpu->arch.mmu_page_cache);
kvm_timer_vcpu_terminate(vcpu);
kvm_pmu_vcpu_destroy(vcpu);
kvm_arm_vcpu_destroy(vcpu);
}
int kvm_cpu_has_pending_timer(struct kvm_vcpu *vcpu)
{
return kvm_timer_is_pending(vcpu);
}
void kvm_arch_vcpu_blocking(struct kvm_vcpu *vcpu)
{
/*
* If we're about to block (most likely because we've just hit a
* WFI), we need to sync back the state of the GIC CPU interface
* so that we have the latest PMR and group enables. This ensures
* that kvm_arch_vcpu_runnable has up-to-date data to decide
* whether we have pending interrupts.
*
* For the same reason, we want to tell GICv4 that we need
* doorbells to be signalled, should an interrupt become pending.
*/
preempt_disable();
kvm_vgic_vmcr_sync(vcpu);
vgic_v4_put(vcpu, true);
preempt_enable();
}
void kvm_arch_vcpu_unblocking(struct kvm_vcpu *vcpu)
{
preempt_disable();
vgic_v4_load(vcpu);
preempt_enable();
}
void kvm_arch_vcpu_load(struct kvm_vcpu *vcpu, int cpu)
{
struct kvm_s2_mmu *mmu;
int *last_ran;
mmu = vcpu->arch.hw_mmu;
last_ran = this_cpu_ptr(mmu->last_vcpu_ran);
/*
* We guarantee that both TLBs and I-cache are private to each
* vcpu. If detecting that a vcpu from the same VM has
* previously run on the same physical CPU, call into the
* hypervisor code to nuke the relevant contexts.
*
* We might get preempted before the vCPU actually runs, but
* over-invalidation doesn't affect correctness.
*/
if (*last_ran != vcpu->vcpu_id) {
kvm_call_hyp(__kvm_flush_cpu_context, mmu);
*last_ran = vcpu->vcpu_id;
}
vcpu->cpu = cpu;
kvm_vgic_load(vcpu);
kvm_timer_vcpu_load(vcpu);
if (has_vhe())
kvm_vcpu_load_sysregs_vhe(vcpu);
kvm_arch_vcpu_load_fp(vcpu);
kvm_vcpu_pmu_restore_guest(vcpu);
if (kvm_arm_is_pvtime_enabled(&vcpu->arch))
kvm_make_request(KVM_REQ_RECORD_STEAL, vcpu);
if (single_task_running())
vcpu_clear_wfx_traps(vcpu);
else
vcpu_set_wfx_traps(vcpu);
if (vcpu_has_ptrauth(vcpu))
vcpu_ptrauth_disable(vcpu);
kvm_arch_vcpu_load_debug_state_flags(vcpu);
}
void kvm_arch_vcpu_put(struct kvm_vcpu *vcpu)
{
kvm_arch_vcpu_put_debug_state_flags(vcpu);
kvm_arch_vcpu_put_fp(vcpu);
if (has_vhe())
kvm_vcpu_put_sysregs_vhe(vcpu);
kvm_timer_vcpu_put(vcpu);
kvm_vgic_put(vcpu);
kvm_vcpu_pmu_restore_host(vcpu);
vcpu->cpu = -1;
}
static void vcpu_power_off(struct kvm_vcpu *vcpu)
{
vcpu->arch.power_off = true;
kvm_make_request(KVM_REQ_SLEEP, vcpu);
kvm_vcpu_kick(vcpu);
}
int kvm_arch_vcpu_ioctl_get_mpstate(struct kvm_vcpu *vcpu,
struct kvm_mp_state *mp_state)
{
if (vcpu->arch.power_off)
mp_state->mp_state = KVM_MP_STATE_STOPPED;
else
mp_state->mp_state = KVM_MP_STATE_RUNNABLE;
return 0;
}
int kvm_arch_vcpu_ioctl_set_mpstate(struct kvm_vcpu *vcpu,
struct kvm_mp_state *mp_state)
{
int ret = 0;
switch (mp_state->mp_state) {
case KVM_MP_STATE_RUNNABLE:
vcpu->arch.power_off = false;
break;
case KVM_MP_STATE_STOPPED:
vcpu_power_off(vcpu);
break;
default:
ret = -EINVAL;
}
return ret;
}
/**
* kvm_arch_vcpu_runnable - determine if the vcpu can be scheduled
* @v: The VCPU pointer
*
* If the guest CPU is not waiting for interrupts or an interrupt line is
* asserted, the CPU is by definition runnable.
*/
int kvm_arch_vcpu_runnable(struct kvm_vcpu *v)
{
bool irq_lines = *vcpu_hcr(v) & (HCR_VI | HCR_VF);
return ((irq_lines || kvm_vgic_vcpu_pending_irq(v))
&& !v->arch.power_off && !v->arch.pause);
}
bool kvm_arch_vcpu_in_kernel(struct kvm_vcpu *vcpu)
{
return vcpu_mode_priv(vcpu);
}
/* Just ensure a guest exit from a particular CPU */
static void exit_vm_noop(void *info)
{
}
void force_vm_exit(const cpumask_t *mask)
{
preempt_disable();
smp_call_function_many(mask, exit_vm_noop, NULL, true);
preempt_enable();
}
/**
* need_new_vmid_gen - check that the VMID is still valid
* @vmid: The VMID to check
*
* return true if there is a new generation of VMIDs being used
*
* The hardware supports a limited set of values with the value zero reserved
* for the host, so we check if an assigned value belongs to a previous
* generation, which requires us to assign a new value. If we're the first to
* use a VMID for the new generation, we must flush necessary caches and TLBs
* on all CPUs.
*/
static bool need_new_vmid_gen(struct kvm_vmid *vmid)
{
u64 current_vmid_gen = atomic64_read(&kvm_vmid_gen);
smp_rmb(); /* Orders read of kvm_vmid_gen and kvm->arch.vmid */
return unlikely(READ_ONCE(vmid->vmid_gen) != current_vmid_gen);
}
/**
* update_vmid - Update the vmid with a valid VMID for the current generation
* @vmid: The stage-2 VMID information struct
*/
static void update_vmid(struct kvm_vmid *vmid)
{
if (!need_new_vmid_gen(vmid))
return;
spin_lock(&kvm_vmid_lock);
/*
* We need to re-check the vmid_gen here to ensure that if another vcpu
* already allocated a valid vmid for this vm, then this vcpu should
* use the same vmid.
*/
if (!need_new_vmid_gen(vmid)) {
spin_unlock(&kvm_vmid_lock);
return;
}
/* First user of a new VMID generation? */
if (unlikely(kvm_next_vmid == 0)) {
atomic64_inc(&kvm_vmid_gen);
kvm_next_vmid = 1;
/*
* On SMP we know no other CPUs can use this CPU's or each
* other's VMID after force_vm_exit returns since the
* kvm_vmid_lock blocks them from reentry to the guest.
*/
force_vm_exit(cpu_all_mask);
/*
* Now broadcast TLB + ICACHE invalidation over the inner
* shareable domain to make sure all data structures are
* clean.
*/
kvm_call_hyp(__kvm_flush_vm_context);
}
vmid->vmid = kvm_next_vmid;
kvm_next_vmid++;
kvm_next_vmid &= (1 << kvm_get_vmid_bits()) - 1;
smp_wmb();
WRITE_ONCE(vmid->vmid_gen, atomic64_read(&kvm_vmid_gen));
spin_unlock(&kvm_vmid_lock);
}
static int kvm_vcpu_first_run_init(struct kvm_vcpu *vcpu)
{
struct kvm *kvm = vcpu->kvm;
int ret = 0;
if (likely(vcpu->arch.has_run_once))
return 0;
if (!kvm_arm_vcpu_is_finalized(vcpu))
return -EPERM;
vcpu->arch.has_run_once = true;
kvm_arm_vcpu_init_debug(vcpu);
if (likely(irqchip_in_kernel(kvm))) {
/*
* Map the VGIC hardware resources before running a vcpu the
* first time on this VM.
*/
ret = kvm_vgic_map_resources(kvm);
if (ret)
return ret;
} else {
/*
* Tell the rest of the code that there are userspace irqchip
* VMs in the wild.
*/
static_branch_inc(&userspace_irqchip_in_use);
}
ret = kvm_timer_enable(vcpu);
if (ret)
return ret;
ret = kvm_arm_pmu_v3_enable(vcpu);
return ret;
}
bool kvm_arch_intc_initialized(struct kvm *kvm)
{
return vgic_initialized(kvm);
}
void kvm_arm_halt_guest(struct kvm *kvm)
{
int i;
struct kvm_vcpu *vcpu;
kvm_for_each_vcpu(i, vcpu, kvm)
vcpu->arch.pause = true;
kvm_make_all_cpus_request(kvm, KVM_REQ_SLEEP);
}
void kvm_arm_resume_guest(struct kvm *kvm)
{
int i;
struct kvm_vcpu *vcpu;
kvm_for_each_vcpu(i, vcpu, kvm) {
vcpu->arch.pause = false;
rcuwait_wake_up(kvm_arch_vcpu_get_wait(vcpu));
}
}
static void vcpu_req_sleep(struct kvm_vcpu *vcpu)
{
struct rcuwait *wait = kvm_arch_vcpu_get_wait(vcpu);
rcuwait_wait_event(wait,
(!vcpu->arch.power_off) &&(!vcpu->arch.pause),
TASK_INTERRUPTIBLE);
if (vcpu->arch.power_off || vcpu->arch.pause) {
/* Awaken to handle a signal, request we sleep again later. */
kvm_make_request(KVM_REQ_SLEEP, vcpu);
}
/*
* Make sure we will observe a potential reset request if we've
* observed a change to the power state. Pairs with the smp_wmb() in
* kvm_psci_vcpu_on().
*/
smp_rmb();
}
static int kvm_vcpu_initialized(struct kvm_vcpu *vcpu)
{
return vcpu->arch.target >= 0;
}
static void check_vcpu_requests(struct kvm_vcpu *vcpu)
{
if (kvm_request_pending(vcpu)) {
if (kvm_check_request(KVM_REQ_SLEEP, vcpu))
vcpu_req_sleep(vcpu);
if (kvm_check_request(KVM_REQ_VCPU_RESET, vcpu))
kvm_reset_vcpu(vcpu);
/*
* Clear IRQ_PENDING requests that were made to guarantee
* that a VCPU sees new virtual interrupts.
*/
kvm_check_request(KVM_REQ_IRQ_PENDING, vcpu);
if (kvm_check_request(KVM_REQ_RECORD_STEAL, vcpu))
kvm_update_stolen_time(vcpu);
if (kvm_check_request(KVM_REQ_RELOAD_GICv4, vcpu)) {
/* The distributor enable bits were changed */
preempt_disable();
vgic_v4_put(vcpu, false);
vgic_v4_load(vcpu);
preempt_enable();
}
if (kvm_check_request(KVM_REQ_RELOAD_PMU, vcpu))
kvm_pmu_handle_pmcr(vcpu,
__vcpu_sys_reg(vcpu, PMCR_EL0));
}
}
static bool vcpu_mode_is_bad_32bit(struct kvm_vcpu *vcpu)
{
if (likely(!vcpu_mode_is_32bit(vcpu)))
return false;
return !system_supports_32bit_el0() ||
static_branch_unlikely(&arm64_mismatched_32bit_el0);
}
/**
* kvm_arch_vcpu_ioctl_run - the main VCPU run function to execute guest code
* @vcpu: The VCPU pointer
*
* This function is called through the VCPU_RUN ioctl called from user space. It
* will execute VM code in a loop until the time slice for the process is used
* or some emulation is needed from user space in which case the function will
* return with return value 0 and with the kvm_run structure filled in with the
* required data for the requested emulation.
*/
int kvm_arch_vcpu_ioctl_run(struct kvm_vcpu *vcpu)
{
struct kvm_run *run = vcpu->run;
int ret;
if (unlikely(!kvm_vcpu_initialized(vcpu)))
return -ENOEXEC;
ret = kvm_vcpu_first_run_init(vcpu);
if (ret)
return ret;
if (run->exit_reason == KVM_EXIT_MMIO) {
ret = kvm_handle_mmio_return(vcpu);
if (ret)
return ret;
}
vcpu_load(vcpu);
if (run->immediate_exit) {
ret = -EINTR;
goto out;
}
kvm_sigset_activate(vcpu);
ret = 1;
run->exit_reason = KVM_EXIT_UNKNOWN;
while (ret > 0) {
/*
* Check conditions before entering the guest
*/
cond_resched();
update_vmid(&vcpu->arch.hw_mmu->vmid);
check_vcpu_requests(vcpu);
/*
* Preparing the interrupts to be injected also
* involves poking the GIC, which must be done in a
* non-preemptible context.
*/
preempt_disable();
kvm_pmu_flush_hwstate(vcpu);
local_irq_disable();
kvm_vgic_flush_hwstate(vcpu);
/*
* Exit if we have a signal pending so that we can deliver the
* signal to user space.
*/
if (signal_pending(current)) {
ret = -EINTR;
run->exit_reason = KVM_EXIT_INTR;
}
/*
* If we're using a userspace irqchip, then check if we need
* to tell a userspace irqchip about timer or PMU level
* changes and if so, exit to userspace (the actual level
* state gets updated in kvm_timer_update_run and
* kvm_pmu_update_run below).
*/
if (static_branch_unlikely(&userspace_irqchip_in_use)) {
if (kvm_timer_should_notify_user(vcpu) ||
kvm_pmu_should_notify_user(vcpu)) {
ret = -EINTR;
run->exit_reason = KVM_EXIT_INTR;
}
}
/*
* Ensure we set mode to IN_GUEST_MODE after we disable
* interrupts and before the final VCPU requests check.
* See the comment in kvm_vcpu_exiting_guest_mode() and
* Documentation/virt/kvm/vcpu-requests.rst
*/
smp_store_mb(vcpu->mode, IN_GUEST_MODE);
if (ret <= 0 || need_new_vmid_gen(&vcpu->arch.hw_mmu->vmid) ||
kvm_request_pending(vcpu)) {
vcpu->mode = OUTSIDE_GUEST_MODE;
isb(); /* Ensure work in x_flush_hwstate is committed */
kvm_pmu_sync_hwstate(vcpu);
if (static_branch_unlikely(&userspace_irqchip_in_use))
kvm_timer_sync_user(vcpu);
kvm_vgic_sync_hwstate(vcpu);
local_irq_enable();
preempt_enable();
continue;
}
kvm_arm_setup_debug(vcpu);
/**************************************************************
* Enter the guest
*/
trace_kvm_entry(*vcpu_pc(vcpu));
guest_enter_irqoff();
ret = kvm_call_hyp_ret(__kvm_vcpu_run, vcpu);
vcpu->mode = OUTSIDE_GUEST_MODE;
vcpu->stat.exits++;
/*
* Back from guest
*************************************************************/
kvm_arm_clear_debug(vcpu);
/*
* We must sync the PMU state before the vgic state so
* that the vgic can properly sample the updated state of the
* interrupt line.
*/
kvm_pmu_sync_hwstate(vcpu);
/*
* Sync the vgic state before syncing the timer state because
* the timer code needs to know if the virtual timer
* interrupts are active.
*/
kvm_vgic_sync_hwstate(vcpu);
/*
* Sync the timer hardware state before enabling interrupts as
* we don't want vtimer interrupts to race with syncing the
* timer virtual interrupt state.
*/
if (static_branch_unlikely(&userspace_irqchip_in_use))
kvm_timer_sync_user(vcpu);
kvm_arch_vcpu_ctxsync_fp(vcpu);
/*
* We may have taken a host interrupt in HYP mode (ie
* while executing the guest). This interrupt is still
* pending, as we haven't serviced it yet!
*
* We're now back in SVC mode, with interrupts
* disabled. Enabling the interrupts now will have
* the effect of taking the interrupt again, in SVC
* mode this time.
*/
local_irq_enable();
/*
* We do local_irq_enable() before calling guest_exit() so
* that if a timer interrupt hits while running the guest we
* account that tick as being spent in the guest. We enable
* preemption after calling guest_exit() so that if we get
* preempted we make sure ticks after that is not counted as
* guest time.
*/
guest_exit();
trace_kvm_exit(ret, kvm_vcpu_trap_get_class(vcpu), *vcpu_pc(vcpu));
/* Exit types that need handling before we can be preempted */
handle_exit_early(vcpu, ret);
preempt_enable();
/*
* The ARMv8 architecture doesn't give the hypervisor
* a mechanism to prevent a guest from dropping to AArch32 EL0
* if implemented by the CPU. If we spot the guest in such
* state and that we decided it wasn't supposed to do so (like
* with the asymmetric AArch32 case), return to userspace with
* a fatal error.
*/
if (vcpu_mode_is_bad_32bit(vcpu)) {
/*
* As we have caught the guest red-handed, decide that
* it isn't fit for purpose anymore by making the vcpu
* invalid. The VMM can try and fix it by issuing a
* KVM_ARM_VCPU_INIT if it really wants to.
*/
vcpu->arch.target = -1;
ret = ARM_EXCEPTION_IL;
}
ret = handle_exit(vcpu, ret);
}
/* Tell userspace about in-kernel device output levels */
if (unlikely(!irqchip_in_kernel(vcpu->kvm))) {
kvm_timer_update_run(vcpu);
kvm_pmu_update_run(vcpu);
}
kvm_sigset_deactivate(vcpu);
out:
/*
* In the unlikely event that we are returning to userspace
* with pending exceptions or PC adjustment, commit these
* adjustments in order to give userspace a consistent view of
* the vcpu state. Note that this relies on __kvm_adjust_pc()
* being preempt-safe on VHE.
*/
if (unlikely(vcpu->arch.flags & (KVM_ARM64_PENDING_EXCEPTION |
KVM_ARM64_INCREMENT_PC)))
kvm_call_hyp(__kvm_adjust_pc, vcpu);
vcpu_put(vcpu);
return ret;
}
static int vcpu_interrupt_line(struct kvm_vcpu *vcpu, int number, bool level)
{
int bit_index;
bool set;
unsigned long *hcr;
if (number == KVM_ARM_IRQ_CPU_IRQ)
bit_index = __ffs(HCR_VI);
else /* KVM_ARM_IRQ_CPU_FIQ */
bit_index = __ffs(HCR_VF);
hcr = vcpu_hcr(vcpu);
if (level)
set = test_and_set_bit(bit_index, hcr);
else
set = test_and_clear_bit(bit_index, hcr);
/*
* If we didn't change anything, no need to wake up or kick other CPUs
*/
if (set == level)
return 0;
/*
* The vcpu irq_lines field was updated, wake up sleeping VCPUs and
* trigger a world-switch round on the running physical CPU to set the
* virtual IRQ/FIQ fields in the HCR appropriately.
*/
kvm_make_request(KVM_REQ_IRQ_PENDING, vcpu);
kvm_vcpu_kick(vcpu);
return 0;
}
int kvm_vm_ioctl_irq_line(struct kvm *kvm, struct kvm_irq_level *irq_level,
bool line_status)
{
u32 irq = irq_level->irq;
unsigned int irq_type, vcpu_idx, irq_num;
int nrcpus = atomic_read(&kvm->online_vcpus);
struct kvm_vcpu *vcpu = NULL;
bool level = irq_level->level;
irq_type = (irq >> KVM_ARM_IRQ_TYPE_SHIFT) & KVM_ARM_IRQ_TYPE_MASK;
vcpu_idx = (irq >> KVM_ARM_IRQ_VCPU_SHIFT) & KVM_ARM_IRQ_VCPU_MASK;
vcpu_idx += ((irq >> KVM_ARM_IRQ_VCPU2_SHIFT) & KVM_ARM_IRQ_VCPU2_MASK) * (KVM_ARM_IRQ_VCPU_MASK + 1);
irq_num = (irq >> KVM_ARM_IRQ_NUM_SHIFT) & KVM_ARM_IRQ_NUM_MASK;
trace_kvm_irq_line(irq_type, vcpu_idx, irq_num, irq_level->level);
switch (irq_type) {
case KVM_ARM_IRQ_TYPE_CPU:
if (irqchip_in_kernel(kvm))
return -ENXIO;
if (vcpu_idx >= nrcpus)