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|
// SPDX-License-Identifier: GPL-2.0
/*
* Copyright (C) 2019 Western Digital Corporation or its affiliates.
*
* Authors:
* Anup Patel <anup.patel@wdc.com>
*/
#include <linux/bitops.h>
#include <linux/entry-kvm.h>
#include <linux/errno.h>
#include <linux/err.h>
#include <linux/kdebug.h>
#include <linux/module.h>
#include <linux/percpu.h>
#include <linux/vmalloc.h>
#include <linux/sched/signal.h>
#include <linux/fs.h>
#include <linux/kvm_host.h>
#include <asm/csr.h>
#include <asm/cacheflush.h>
#include <asm/kvm_vcpu_vector.h>
const struct _kvm_stats_desc kvm_vcpu_stats_desc[] = {
KVM_GENERIC_VCPU_STATS(),
STATS_DESC_COUNTER(VCPU, ecall_exit_stat),
STATS_DESC_COUNTER(VCPU, wfi_exit_stat),
STATS_DESC_COUNTER(VCPU, mmio_exit_user),
STATS_DESC_COUNTER(VCPU, mmio_exit_kernel),
STATS_DESC_COUNTER(VCPU, csr_exit_user),
STATS_DESC_COUNTER(VCPU, csr_exit_kernel),
STATS_DESC_COUNTER(VCPU, signal_exits),
STATS_DESC_COUNTER(VCPU, exits)
};
const struct kvm_stats_header kvm_vcpu_stats_header = {
.name_size = KVM_STATS_NAME_SIZE,
.num_desc = ARRAY_SIZE(kvm_vcpu_stats_desc),
.id_offset = sizeof(struct kvm_stats_header),
.desc_offset = sizeof(struct kvm_stats_header) + KVM_STATS_NAME_SIZE,
.data_offset = sizeof(struct kvm_stats_header) + KVM_STATS_NAME_SIZE +
sizeof(kvm_vcpu_stats_desc),
};
static void kvm_riscv_reset_vcpu(struct kvm_vcpu *vcpu)
{
struct kvm_vcpu_csr *csr = &vcpu->arch.guest_csr;
struct kvm_vcpu_csr *reset_csr = &vcpu->arch.guest_reset_csr;
struct kvm_cpu_context *cntx = &vcpu->arch.guest_context;
struct kvm_cpu_context *reset_cntx = &vcpu->arch.guest_reset_context;
bool loaded;
/**
* The preemption should be disabled here because it races with
* kvm_sched_out/kvm_sched_in(called from preempt notifiers) which
* also calls vcpu_load/put.
*/
get_cpu();
loaded = (vcpu->cpu != -1);
if (loaded)
kvm_arch_vcpu_put(vcpu);
vcpu->arch.last_exit_cpu = -1;
memcpy(csr, reset_csr, sizeof(*csr));
memcpy(cntx, reset_cntx, sizeof(*cntx));
kvm_riscv_vcpu_fp_reset(vcpu);
kvm_riscv_vcpu_vector_reset(vcpu);
kvm_riscv_vcpu_timer_reset(vcpu);
kvm_riscv_vcpu_aia_reset(vcpu);
bitmap_zero(vcpu->arch.irqs_pending, KVM_RISCV_VCPU_NR_IRQS);
bitmap_zero(vcpu->arch.irqs_pending_mask, KVM_RISCV_VCPU_NR_IRQS);
kvm_riscv_vcpu_pmu_reset(vcpu);
vcpu->arch.hfence_head = 0;
vcpu->arch.hfence_tail = 0;
memset(vcpu->arch.hfence_queue, 0, sizeof(vcpu->arch.hfence_queue));
/* Reset the guest CSRs for hotplug usecase */
if (loaded)
kvm_arch_vcpu_load(vcpu, smp_processor_id());
put_cpu();
}
int kvm_arch_vcpu_precreate(struct kvm *kvm, unsigned int id)
{
return 0;
}
int kvm_arch_vcpu_create(struct kvm_vcpu *vcpu)
{
int rc;
struct kvm_cpu_context *cntx;
struct kvm_vcpu_csr *reset_csr = &vcpu->arch.guest_reset_csr;
/* Mark this VCPU never ran */
vcpu->arch.ran_atleast_once = false;
vcpu->arch.mmu_page_cache.gfp_zero = __GFP_ZERO;
bitmap_zero(vcpu->arch.isa, RISCV_ISA_EXT_MAX);
/* Setup ISA features available to VCPU */
kvm_riscv_vcpu_setup_isa(vcpu);
/* Setup vendor, arch, and implementation details */
vcpu->arch.mvendorid = sbi_get_mvendorid();
vcpu->arch.marchid = sbi_get_marchid();
vcpu->arch.mimpid = sbi_get_mimpid();
/* Setup VCPU hfence queue */
spin_lock_init(&vcpu->arch.hfence_lock);
/* Setup reset state of shadow SSTATUS and HSTATUS CSRs */
cntx = &vcpu->arch.guest_reset_context;
cntx->sstatus = SR_SPP | SR_SPIE;
cntx->hstatus = 0;
cntx->hstatus |= HSTATUS_VTW;
cntx->hstatus |= HSTATUS_SPVP;
cntx->hstatus |= HSTATUS_SPV;
if (kvm_riscv_vcpu_alloc_vector_context(vcpu, cntx))
return -ENOMEM;
/* By default, make CY, TM, and IR counters accessible in VU mode */
reset_csr->scounteren = 0x7;
/* Setup VCPU timer */
kvm_riscv_vcpu_timer_init(vcpu);
/* setup performance monitoring */
kvm_riscv_vcpu_pmu_init(vcpu);
/* Setup VCPU AIA */
rc = kvm_riscv_vcpu_aia_init(vcpu);
if (rc)
return rc;
/* Reset VCPU */
kvm_riscv_reset_vcpu(vcpu);
return 0;
}
void kvm_arch_vcpu_postcreate(struct kvm_vcpu *vcpu)
{
/**
* vcpu with id 0 is the designated boot cpu.
* Keep all vcpus with non-zero id in power-off state so that
* they can be brought up using SBI HSM extension.
*/
if (vcpu->vcpu_idx != 0)
kvm_riscv_vcpu_power_off(vcpu);
}
void kvm_arch_vcpu_destroy(struct kvm_vcpu *vcpu)
{
/* Cleanup VCPU AIA context */
kvm_riscv_vcpu_aia_deinit(vcpu);
/* Cleanup VCPU timer */
kvm_riscv_vcpu_timer_deinit(vcpu);
kvm_riscv_vcpu_pmu_deinit(vcpu);
/* Free unused pages pre-allocated for G-stage page table mappings */
kvm_mmu_free_memory_cache(&vcpu->arch.mmu_page_cache);
/* Free vector context space for host and guest kernel */
kvm_riscv_vcpu_free_vector_context(vcpu);
}
int kvm_cpu_has_pending_timer(struct kvm_vcpu *vcpu)
{
return kvm_riscv_vcpu_timer_pending(vcpu);
}
void kvm_arch_vcpu_blocking(struct kvm_vcpu *vcpu)
{
kvm_riscv_aia_wakeon_hgei(vcpu, true);
}
void kvm_arch_vcpu_unblocking(struct kvm_vcpu *vcpu)
{
kvm_riscv_aia_wakeon_hgei(vcpu, false);
}
int kvm_arch_vcpu_runnable(struct kvm_vcpu *vcpu)
{
return (kvm_riscv_vcpu_has_interrupts(vcpu, -1UL) &&
!vcpu->arch.power_off && !vcpu->arch.pause);
}
int kvm_arch_vcpu_should_kick(struct kvm_vcpu *vcpu)
{
return kvm_vcpu_exiting_guest_mode(vcpu) == IN_GUEST_MODE;
}
bool kvm_arch_vcpu_in_kernel(struct kvm_vcpu *vcpu)
{
return (vcpu->arch.guest_context.sstatus & SR_SPP) ? true : false;
}
vm_fault_t kvm_arch_vcpu_fault(struct kvm_vcpu *vcpu, struct vm_fault *vmf)
{
return VM_FAULT_SIGBUS;
}
long kvm_arch_vcpu_async_ioctl(struct file *filp,
unsigned int ioctl, unsigned long arg)
{
struct kvm_vcpu *vcpu = filp->private_data;
void __user *argp = (void __user *)arg;
if (ioctl == KVM_INTERRUPT) {
struct kvm_interrupt irq;
if (copy_from_user(&irq, argp, sizeof(irq)))
return -EFAULT;
if (irq.irq == KVM_INTERRUPT_SET)
return kvm_riscv_vcpu_set_interrupt(vcpu, IRQ_VS_EXT);
else
return kvm_riscv_vcpu_unset_interrupt(vcpu, IRQ_VS_EXT);
}
return -ENOIOCTLCMD;
}
long kvm_arch_vcpu_ioctl(struct file *filp,
unsigned int ioctl, unsigned long arg)
{
struct kvm_vcpu *vcpu = filp->private_data;
void __user *argp = (void __user *)arg;
long r = -EINVAL;
switch (ioctl) {
case KVM_SET_ONE_REG:
case KVM_GET_ONE_REG: {
struct kvm_one_reg reg;
r = -EFAULT;
if (copy_from_user(®, argp, sizeof(reg)))
break;
if (ioctl == KVM_SET_ONE_REG)
r = kvm_riscv_vcpu_set_reg(vcpu, ®);
else
r = kvm_riscv_vcpu_get_reg(vcpu, ®);
break;
}
default:
break;
}
return r;
}
int kvm_arch_vcpu_ioctl_get_sregs(struct kvm_vcpu *vcpu,
struct kvm_sregs *sregs)
{
return -EINVAL;
}
int kvm_arch_vcpu_ioctl_set_sregs(struct kvm_vcpu *vcpu,
struct kvm_sregs *sregs)
{
return -EINVAL;
}
int kvm_arch_vcpu_ioctl_get_fpu(struct kvm_vcpu *vcpu, struct kvm_fpu *fpu)
{
return -EINVAL;
}
int kvm_arch_vcpu_ioctl_set_fpu(struct kvm_vcpu *vcpu, struct kvm_fpu *fpu)
{
return -EINVAL;
}
int kvm_arch_vcpu_ioctl_translate(struct kvm_vcpu *vcpu,
struct kvm_translation *tr)
{
return -EINVAL;
}
int kvm_arch_vcpu_ioctl_get_regs(struct kvm_vcpu *vcpu, struct kvm_regs *regs)
{
return -EINVAL;
}
int kvm_arch_vcpu_ioctl_set_regs(struct kvm_vcpu *vcpu, struct kvm_regs *regs)
{
return -EINVAL;
}
void kvm_riscv_vcpu_flush_interrupts(struct kvm_vcpu *vcpu)
{
struct kvm_vcpu_csr *csr = &vcpu->arch.guest_csr;
unsigned long mask, val;
if (READ_ONCE(vcpu->arch.irqs_pending_mask[0])) {
mask = xchg_acquire(&vcpu->arch.irqs_pending_mask[0], 0);
val = READ_ONCE(vcpu->arch.irqs_pending[0]) & mask;
csr->hvip &= ~mask;
csr->hvip |= val;
}
/* Flush AIA high interrupts */
kvm_riscv_vcpu_aia_flush_interrupts(vcpu);
}
void kvm_riscv_vcpu_sync_interrupts(struct kvm_vcpu *vcpu)
{
unsigned long hvip;
struct kvm_vcpu_arch *v = &vcpu->arch;
struct kvm_vcpu_csr *csr = &vcpu->arch.guest_csr;
/* Read current HVIP and VSIE CSRs */
csr->vsie = csr_read(CSR_VSIE);
/* Sync-up HVIP.VSSIP bit changes does by Guest */
hvip = csr_read(CSR_HVIP);
if ((csr->hvip ^ hvip) & (1UL << IRQ_VS_SOFT)) {
if (hvip & (1UL << IRQ_VS_SOFT)) {
if (!test_and_set_bit(IRQ_VS_SOFT,
v->irqs_pending_mask))
set_bit(IRQ_VS_SOFT, v->irqs_pending);
} else {
if (!test_and_set_bit(IRQ_VS_SOFT,
v->irqs_pending_mask))
clear_bit(IRQ_VS_SOFT, v->irqs_pending);
}
}
/* Sync-up AIA high interrupts */
kvm_riscv_vcpu_aia_sync_interrupts(vcpu);
/* Sync-up timer CSRs */
kvm_riscv_vcpu_timer_sync(vcpu);
}
int kvm_riscv_vcpu_set_interrupt(struct kvm_vcpu *vcpu, unsigned int irq)
{
/*
* We only allow VS-mode software, timer, and external
* interrupts when irq is one of the local interrupts
* defined by RISC-V privilege specification.
*/
if (irq < IRQ_LOCAL_MAX &&
irq != IRQ_VS_SOFT &&
irq != IRQ_VS_TIMER &&
irq != IRQ_VS_EXT)
return -EINVAL;
set_bit(irq, vcpu->arch.irqs_pending);
smp_mb__before_atomic();
set_bit(irq, vcpu->arch.irqs_pending_mask);
kvm_vcpu_kick(vcpu);
return 0;
}
int kvm_riscv_vcpu_unset_interrupt(struct kvm_vcpu *vcpu, unsigned int irq)
{
/*
* We only allow VS-mode software, timer, and external
* interrupts when irq is one of the local interrupts
* defined by RISC-V privilege specification.
*/
if (irq < IRQ_LOCAL_MAX &&
irq != IRQ_VS_SOFT &&
irq != IRQ_VS_TIMER &&
irq != IRQ_VS_EXT)
return -EINVAL;
clear_bit(irq, vcpu->arch.irqs_pending);
smp_mb__before_atomic();
set_bit(irq, vcpu->arch.irqs_pending_mask);
return 0;
}
bool kvm_riscv_vcpu_has_interrupts(struct kvm_vcpu *vcpu, u64 mask)
{
unsigned long ie;
ie = ((vcpu->arch.guest_csr.vsie & VSIP_VALID_MASK)
<< VSIP_TO_HVIP_SHIFT) & (unsigned long)mask;
ie |= vcpu->arch.guest_csr.vsie & ~IRQ_LOCAL_MASK &
(unsigned long)mask;
if (READ_ONCE(vcpu->arch.irqs_pending[0]) & ie)
return true;
/* Check AIA high interrupts */
return kvm_riscv_vcpu_aia_has_interrupts(vcpu, mask);
}
void kvm_riscv_vcpu_power_off(struct kvm_vcpu *vcpu)
{
vcpu->arch.power_off = true;
kvm_make_request(KVM_REQ_SLEEP, vcpu);
kvm_vcpu_kick(vcpu);
}
void kvm_riscv_vcpu_power_on(struct kvm_vcpu *vcpu)
{
vcpu->arch.power_off = false;
kvm_vcpu_wake_up(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:
kvm_riscv_vcpu_power_off(vcpu);
break;
default:
ret = -EINVAL;
}
return ret;
}
int kvm_arch_vcpu_ioctl_set_guest_debug(struct kvm_vcpu *vcpu,
struct kvm_guest_debug *dbg)
{
/* TODO; To be implemented later. */
return -EINVAL;
}
static void kvm_riscv_vcpu_update_config(const unsigned long *isa)
{
u64 henvcfg = 0;
if (riscv_isa_extension_available(isa, SVPBMT))
henvcfg |= ENVCFG_PBMTE;
if (riscv_isa_extension_available(isa, SSTC))
henvcfg |= ENVCFG_STCE;
if (riscv_isa_extension_available(isa, ZICBOM))
henvcfg |= (ENVCFG_CBIE | ENVCFG_CBCFE);
if (riscv_isa_extension_available(isa, ZICBOZ))
henvcfg |= ENVCFG_CBZE;
csr_write(CSR_HENVCFG, henvcfg);
#ifdef CONFIG_32BIT
csr_write(CSR_HENVCFGH, henvcfg >> 32);
#endif
}
void kvm_arch_vcpu_load(struct kvm_vcpu *vcpu, int cpu)
{
struct kvm_vcpu_csr *csr = &vcpu->arch.guest_csr;
csr_write(CSR_VSSTATUS, csr->vsstatus);
csr_write(CSR_VSIE, csr->vsie);
csr_write(CSR_VSTVEC, csr->vstvec);
csr_write(CSR_VSSCRATCH, csr->vsscratch);
csr_write(CSR_VSEPC, csr->vsepc);
csr_write(CSR_VSCAUSE, csr->vscause);
csr_write(CSR_VSTVAL, csr->vstval);
csr_write(CSR_HVIP, csr->hvip);
csr_write(CSR_VSATP, csr->vsatp);
kvm_riscv_vcpu_update_config(vcpu->arch.isa);
kvm_riscv_gstage_update_hgatp(vcpu);
kvm_riscv_vcpu_timer_restore(vcpu);
kvm_riscv_vcpu_host_fp_save(&vcpu->arch.host_context);
kvm_riscv_vcpu_guest_fp_restore(&vcpu->arch.guest_context,
vcpu->arch.isa);
kvm_riscv_vcpu_host_vector_save(&vcpu->arch.host_context);
kvm_riscv_vcpu_guest_vector_restore(&vcpu->arch.guest_context,
vcpu->arch.isa);
kvm_riscv_vcpu_aia_load(vcpu, cpu);
vcpu->cpu = cpu;
}
void kvm_arch_vcpu_put(struct kvm_vcpu *vcpu)
{
struct kvm_vcpu_csr *csr = &vcpu->arch.guest_csr;
vcpu->cpu = -1;
kvm_riscv_vcpu_aia_put(vcpu);
kvm_riscv_vcpu_guest_fp_save(&vcpu->arch.guest_context,
vcpu->arch.isa);
kvm_riscv_vcpu_host_fp_restore(&vcpu->arch.host_context);
kvm_riscv_vcpu_timer_save(vcpu);
kvm_riscv_vcpu_guest_vector_save(&vcpu->arch.guest_context,
vcpu->arch.isa);
kvm_riscv_vcpu_host_vector_restore(&vcpu->arch.host_context);
csr->vsstatus = csr_read(CSR_VSSTATUS);
csr->vsie = csr_read(CSR_VSIE);
csr->vstvec = csr_read(CSR_VSTVEC);
csr->vsscratch = csr_read(CSR_VSSCRATCH);
csr->vsepc = csr_read(CSR_VSEPC);
csr->vscause = csr_read(CSR_VSCAUSE);
csr->vstval = csr_read(CSR_VSTVAL);
csr->hvip = csr_read(CSR_HVIP);
csr->vsatp = csr_read(CSR_VSATP);
}
static void kvm_riscv_check_vcpu_requests(struct kvm_vcpu *vcpu)
{
struct rcuwait *wait = kvm_arch_vcpu_get_wait(vcpu);
if (kvm_request_pending(vcpu)) {
if (kvm_check_request(KVM_REQ_SLEEP, vcpu)) {
kvm_vcpu_srcu_read_unlock(vcpu);
rcuwait_wait_event(wait,
(!vcpu->arch.power_off) && (!vcpu->arch.pause),
TASK_INTERRUPTIBLE);
kvm_vcpu_srcu_read_lock(vcpu);
if (vcpu->arch.power_off || vcpu->arch.pause) {
/*
* Awaken to handle a signal, request to
* sleep again later.
*/
kvm_make_request(KVM_REQ_SLEEP, vcpu);
}
}
if (kvm_check_request(KVM_REQ_VCPU_RESET, vcpu))
kvm_riscv_reset_vcpu(vcpu);
if (kvm_check_request(KVM_REQ_UPDATE_HGATP, vcpu))
kvm_riscv_gstage_update_hgatp(vcpu);
if (kvm_check_request(KVM_REQ_FENCE_I, vcpu))
kvm_riscv_fence_i_process(vcpu);
/*
* The generic KVM_REQ_TLB_FLUSH is same as
* KVM_REQ_HFENCE_GVMA_VMID_ALL
*/
if (kvm_check_request(KVM_REQ_HFENCE_GVMA_VMID_ALL, vcpu))
kvm_riscv_hfence_gvma_vmid_all_process(vcpu);
if (kvm_check_request(KVM_REQ_HFENCE_VVMA_ALL, vcpu))
kvm_riscv_hfence_vvma_all_process(vcpu);
if (kvm_check_request(KVM_REQ_HFENCE, vcpu))
kvm_riscv_hfence_process(vcpu);
}
}
static void kvm_riscv_update_hvip(struct kvm_vcpu *vcpu)
{
struct kvm_vcpu_csr *csr = &vcpu->arch.guest_csr;
csr_write(CSR_HVIP, csr->hvip);
kvm_riscv_vcpu_aia_update_hvip(vcpu);
}
/*
* Actually run the vCPU, entering an RCU extended quiescent state (EQS) while
* the vCPU is running.
*
* This must be noinstr as instrumentation may make use of RCU, and this is not
* safe during the EQS.
*/
static void noinstr kvm_riscv_vcpu_enter_exit(struct kvm_vcpu *vcpu)
{
guest_state_enter_irqoff();
__kvm_riscv_switch_to(&vcpu->arch);
vcpu->arch.last_exit_cpu = vcpu->cpu;
guest_state_exit_irqoff();
}
int kvm_arch_vcpu_ioctl_run(struct kvm_vcpu *vcpu)
{
int ret;
struct kvm_cpu_trap trap;
struct kvm_run *run = vcpu->run;
/* Mark this VCPU ran at least once */
vcpu->arch.ran_atleast_once = true;
kvm_vcpu_srcu_read_lock(vcpu);
switch (run->exit_reason) {
case KVM_EXIT_MMIO:
/* Process MMIO value returned from user-space */
ret = kvm_riscv_vcpu_mmio_return(vcpu, vcpu->run);
break;
case KVM_EXIT_RISCV_SBI:
/* Process SBI value returned from user-space */
ret = kvm_riscv_vcpu_sbi_return(vcpu, vcpu->run);
break;
case KVM_EXIT_RISCV_CSR:
/* Process CSR value returned from user-space */
ret = kvm_riscv_vcpu_csr_return(vcpu, vcpu->run);
break;
default:
ret = 0;
break;
}
if (ret) {
kvm_vcpu_srcu_read_unlock(vcpu);
return ret;
}
if (run->immediate_exit) {
kvm_vcpu_srcu_read_unlock(vcpu);
return -EINTR;
}
vcpu_load(vcpu);
kvm_sigset_activate(vcpu);
ret = 1;
run->exit_reason = KVM_EXIT_UNKNOWN;
while (ret > 0) {
/* Check conditions before entering the guest */
ret = xfer_to_guest_mode_handle_work(vcpu);
if (ret)
continue;
ret = 1;
kvm_riscv_gstage_vmid_update(vcpu);
kvm_riscv_check_vcpu_requests(vcpu);
preempt_disable();
/* Update AIA HW state before entering guest */
ret = kvm_riscv_vcpu_aia_update(vcpu);
if (ret <= 0) {
preempt_enable();
continue;
}
local_irq_disable();
/*
* 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
*/
vcpu->mode = IN_GUEST_MODE;
kvm_vcpu_srcu_read_unlock(vcpu);
smp_mb__after_srcu_read_unlock();
/*
* We might have got VCPU interrupts updated asynchronously
* so update it in HW.
*/
kvm_riscv_vcpu_flush_interrupts(vcpu);
/* Update HVIP CSR for current CPU */
kvm_riscv_update_hvip(vcpu);
if (ret <= 0 ||
kvm_riscv_gstage_vmid_ver_changed(&vcpu->kvm->arch.vmid) ||
kvm_request_pending(vcpu) ||
xfer_to_guest_mode_work_pending()) {
vcpu->mode = OUTSIDE_GUEST_MODE;
local_irq_enable();
preempt_enable();
kvm_vcpu_srcu_read_lock(vcpu);
continue;
}
/*
* Cleanup stale TLB enteries
*
* Note: This should be done after G-stage VMID has been
* updated using kvm_riscv_gstage_vmid_ver_changed()
*/
kvm_riscv_local_tlb_sanitize(vcpu);
guest_timing_enter_irqoff();
kvm_riscv_vcpu_enter_exit(vcpu);
vcpu->mode = OUTSIDE_GUEST_MODE;
vcpu->stat.exits++;
/*
* Save SCAUSE, STVAL, HTVAL, and HTINST because we might
* get an interrupt between __kvm_riscv_switch_to() and
* local_irq_enable() which can potentially change CSRs.
*/
trap.sepc = vcpu->arch.guest_context.sepc;
trap.scause = csr_read(CSR_SCAUSE);
trap.stval = csr_read(CSR_STVAL);
trap.htval = csr_read(CSR_HTVAL);
trap.htinst = csr_read(CSR_HTINST);
/* Syncup interrupts state with HW */
kvm_riscv_vcpu_sync_interrupts(vcpu);
/*
* We must ensure that any pending interrupts are taken before
* we exit guest timing so that timer ticks are accounted as
* guest time. Transiently unmask interrupts so that any
* pending interrupts are taken.
*
* There's no barrier which ensures that pending interrupts are
* recognised, so we just hope that the CPU takes any pending
* interrupts between the enable and disable.
*/
local_irq_enable();
local_irq_disable();
guest_timing_exit_irqoff();
local_irq_enable();
preempt_enable();
kvm_vcpu_srcu_read_lock(vcpu);
ret = kvm_riscv_vcpu_exit(vcpu, run, &trap);
}
kvm_sigset_deactivate(vcpu);
vcpu_put(vcpu);
kvm_vcpu_srcu_read_unlock(vcpu);
return ret;
}
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