Like pause, replacing power_off with a vcpu request ensures
visibility of changes and avoids the final race before entering
the guest.
Signed-off-by: Andrew Jones <drjones@xxxxxxxxxx>
---
arch/arm/include/asm/kvm_host.h | 4 +---
arch/arm/kvm/arm.c | 32 ++++++++++++++++++--------------
arch/arm/kvm/psci.c | 17 +++++------------
arch/arm64/include/asm/kvm_host.h | 4 +---
4 files changed, 25 insertions(+), 32 deletions(-)
diff --git a/arch/arm/include/asm/kvm_host.h b/arch/arm/include/asm/kvm_host.h
index 52c25536d254..afed5d44634d 100644
--- a/arch/arm/include/asm/kvm_host.h
+++ b/arch/arm/include/asm/kvm_host.h
@@ -46,6 +46,7 @@
#endif
#define KVM_REQ_PAUSE 8
+#define KVM_REQ_POWER_OFF 9
u32 *kvm_vcpu_reg(struct kvm_vcpu *vcpu, u8 reg_num, u32 mode);
int __attribute_const__ kvm_target_cpu(void);
@@ -170,9 +171,6 @@ struct kvm_vcpu_arch {
* here.
*/
- /* vcpu power-off state */
- bool power_off;
-
/* IO related fields */
struct kvm_decode mmio_decode;
diff --git a/arch/arm/kvm/arm.c b/arch/arm/kvm/arm.c
index f3bfbb5f3d96..7ed39060b1cf 100644
--- a/arch/arm/kvm/arm.c
+++ b/arch/arm/kvm/arm.c
@@ -381,7 +381,7 @@ void kvm_arch_vcpu_put(struct kvm_vcpu *vcpu)
int kvm_arch_vcpu_ioctl_get_mpstate(struct kvm_vcpu *vcpu,
struct kvm_mp_state *mp_state)
{
- if (vcpu->arch.power_off)
+ if (test_bit(KVM_REQ_POWER_OFF, &vcpu->requests))
mp_state->mp_state = KVM_MP_STATE_STOPPED;
else
mp_state->mp_state = KVM_MP_STATE_RUNNABLE;
@@ -394,10 +394,10 @@ int kvm_arch_vcpu_ioctl_set_mpstate(struct kvm_vcpu *vcpu,
{
switch (mp_state->mp_state) {
case KVM_MP_STATE_RUNNABLE:
- vcpu->arch.power_off = false;
+ clear_bit(KVM_REQ_POWER_OFF, &vcpu->requests);
break;
case KVM_MP_STATE_STOPPED:
- vcpu->arch.power_off = true;
+ set_bit(KVM_REQ_POWER_OFF, &vcpu->requests);
break;
default:
return -EINVAL;
@@ -415,9 +415,9 @@ int kvm_arch_vcpu_ioctl_set_mpstate(struct kvm_vcpu *vcpu,
*/
int kvm_arch_vcpu_runnable(struct kvm_vcpu *v)
{
- return ((!!v->arch.irq_lines || kvm_vgic_vcpu_pending_irq(v))
- && !v->arch.power_off
- && !test_bit(KVM_REQ_PAUSE, &v->requests));
+ return (!!v->arch.irq_lines || kvm_vgic_vcpu_pending_irq(v)) &&
+ !test_bit(KVM_REQ_POWER_OFF, &v->requests) &&
+ !test_bit(KVM_REQ_PAUSE, &v->requests);
}
/* Just ensure a guest exit from a particular CPU */
@@ -578,8 +578,9 @@ static void vcpu_sleep(struct kvm_vcpu *vcpu)
{
struct swait_queue_head *wq = kvm_arch_vcpu_wq(vcpu);
- swait_event_interruptible(*wq, ((!vcpu->arch.power_off) &&
- (!test_bit(KVM_REQ_PAUSE, &vcpu->requests))));
+ swait_event_interruptible(*wq,
+ !test_bit(KVM_REQ_POWER_OFF, &vcpu->requests) &&
+ !test_bit(KVM_REQ_PAUSE, &vcpu->requests));
}
static int kvm_vcpu_initialized(struct kvm_vcpu *vcpu)
@@ -632,8 +633,11 @@ int kvm_arch_vcpu_ioctl_run(struct kvm_vcpu *vcpu, struct kvm_run *run)
update_vttbr(vcpu->kvm);
- if (vcpu->arch.power_off || test_bit(KVM_REQ_PAUSE, &vcpu->requests))
- vcpu_sleep(vcpu);
+ if (kvm_request_pending(vcpu)) {
+ if (test_bit(KVM_REQ_POWER_OFF, &vcpu->requests) ||
+ test_bit(KVM_REQ_PAUSE, &vcpu->requests))
+ vcpu_sleep(vcpu);
+ }
/*
* Preparing the interrupts to be injected also
@@ -664,8 +668,8 @@ int kvm_arch_vcpu_ioctl_run(struct kvm_vcpu *vcpu, struct kvm_run *run)
WRITE_ONCE(vcpu->mode, IN_GUEST_MODE);
smp_mb();
- if (ret <= 0 || need_new_vmid_gen(vcpu->kvm) ||
- vcpu->arch.power_off || kvm_request_pending(vcpu)) {
+ if (ret <= 0 || need_new_vmid_gen(vcpu->kvm)
+ || kvm_request_pending(vcpu)) {
WRITE_ONCE(vcpu->mode, OUTSIDE_GUEST_MODE);
local_irq_enable();
kvm_pmu_sync_hwstate(vcpu);
@@ -892,9 +896,9 @@ static int kvm_arch_vcpu_ioctl_vcpu_init(struct kvm_vcpu *vcpu,
* Handle the "start in power-off" case.
*/
if (test_bit(KVM_ARM_VCPU_POWER_OFF, vcpu->arch.features))
- vcpu->arch.power_off = true;
+ set_bit(KVM_REQ_POWER_OFF, &vcpu->requests);
else
- vcpu->arch.power_off = false;
+ clear_bit(KVM_REQ_POWER_OFF, &vcpu->requests);
return 0;
}
diff --git a/arch/arm/kvm/psci.c b/arch/arm/kvm/psci.c
index 82fe7eb5b6a7..f732484abc7a 100644
--- a/arch/arm/kvm/psci.c
+++ b/arch/arm/kvm/psci.c
@@ -64,7 +64,7 @@ static unsigned long kvm_psci_vcpu_suspend(struct kvm_vcpu *vcpu)
static void kvm_psci_vcpu_off(struct kvm_vcpu *vcpu)
{
- vcpu->arch.power_off = true;
+ set_bit(KVM_REQ_POWER_OFF, &vcpu->requests);
}
static unsigned long kvm_psci_vcpu_on(struct kvm_vcpu *source_vcpu)
@@ -88,7 +88,7 @@ static unsigned long kvm_psci_vcpu_on(struct kvm_vcpu *source_vcpu)
*/
if (!vcpu)
return PSCI_RET_INVALID_PARAMS;
- if (!vcpu->arch.power_off) {
+ if (!test_bit(KVM_REQ_POWER_OFF, &vcpu->requests)) {
if (kvm_psci_version(source_vcpu) != KVM_ARM_PSCI_0_1)
return PSCI_RET_ALREADY_ON;
else
@@ -116,8 +116,7 @@ static unsigned long kvm_psci_vcpu_on(struct kvm_vcpu *source_vcpu)
* the general puspose registers are undefined upon CPU_ON.
*/
vcpu_set_reg(vcpu, 0, context_id);
- vcpu->arch.power_off = false;
- smp_mb(); /* Make sure the above is visible */
+ clear_bit(KVM_REQ_POWER_OFF, &vcpu->requests);
wq = kvm_arch_vcpu_wq(vcpu);
swake_up(wq);
@@ -154,7 +153,7 @@ static unsigned long kvm_psci_vcpu_affinity_info(struct kvm_vcpu *vcpu)
mpidr = kvm_vcpu_get_mpidr_aff(tmp);
if ((mpidr & target_affinity_mask) == target_affinity) {
matching_cpus++;
- if (!tmp->arch.power_off)
+ if (!test_bit(KVM_REQ_POWER_OFF, &tmp->requests))
return PSCI_0_2_AFFINITY_LEVEL_ON;
}
}
@@ -167,9 +166,6 @@ static unsigned long kvm_psci_vcpu_affinity_info(struct kvm_vcpu *vcpu)
static void kvm_prepare_system_event(struct kvm_vcpu *vcpu, u32 type)
{
- int i;
- struct kvm_vcpu *tmp;
-
/*
* The KVM ABI specifies that a system event exit may call KVM_RUN
* again and may perform shutdown/reboot at a later time that when the
@@ -179,10 +175,7 @@ static void kvm_prepare_system_event(struct kvm_vcpu *vcpu, u32 type)
* after this call is handled and before the VCPUs have been
* re-initialized.
*/
- kvm_for_each_vcpu(i, tmp, vcpu->kvm) {
- tmp->arch.power_off = true;
- kvm_vcpu_kick(tmp);
- }
+ kvm_make_all_cpus_request(vcpu->kvm, KVM_REQ_POWER_OFF);
memset(&vcpu->run->system_event, 0, sizeof(vcpu->run->system_event));
vcpu->run->system_event.type = type;
diff --git a/arch/arm64/include/asm/kvm_host.h b/arch/arm64/include/asm/kvm_host.h
index 6e1271a77e92..e78895f675d0 100644
--- a/arch/arm64/include/asm/kvm_host.h
+++ b/arch/arm64/include/asm/kvm_host.h
@@ -43,6 +43,7 @@
#define KVM_VCPU_MAX_FEATURES 4
#define KVM_REQ_PAUSE 8
+#define KVM_REQ_POWER_OFF 9
int __attribute_const__ kvm_target_cpu(void);
int kvm_reset_vcpu(struct kvm_vcpu *vcpu);
@@ -253,9 +254,6 @@ struct kvm_vcpu_arch {
u32 mdscr_el1;
} guest_debug_preserved;
- /* vcpu power-off state */
- bool power_off;
-
/* IO related fields */
struct kvm_decode mmio_decode;
--
2.9.3
