[PATCH 081/104] KVM: enable in-kernel APIC INIT/SIPI handling

Avi Kivity
2007-09-17T08:57:43Z

From: He, Qing <qing.he@intel.com>

This patch enables INIT/SIPI handling using in-kernel APIC by
introducing a ->mp_state field to emulate the SMP state transition.

[avi: remove smp_processor_id() warning]

Signed-off-by: Qing He <qing.he@intel.com>
Signed-off-by: Xin Li <xin.b.li@intel.com>
Signed-off-by: Avi Kivity <avi@qumranet.com>
---
drivers/kvm/irq.h | 1 +
drivers/kvm/kvm.h | 7 +++++++
drivers/kvm/kvm_main.c | 26 ++++++++++++++++++++------
drivers/kvm/lapic.c | 43 ++++++++++++++++++++++++++++++++++++-------
drivers/kvm/vmx.c | 24 +++++++++++++++++++++---
5 files changed, 85 insertions(+), 16 deletions(-)

diff --git a/drivers/kvm/irq.h b/drivers/kvm/irq.h
index ec46a09..11fc014 100644
--- a/drivers/kvm/irq.h
+++ b/drivers/kvm/irq.h
@@ -138,6 +138,7 @@ int kvm_apic_has_interrupt(struct kvm_vcpu *vcpu);
int kvm_apic_accept_pic_intr(struct kvm_vcpu *vcpu);
int kvm_get_apic_interrupt(struct kvm_vcpu *vcpu);
int kvm_create_lapic(struct kvm_vcpu *vcpu);
+void kvm_lapic_reset(struct kvm_vcpu *vcpu);
void kvm_free_apic(struct kvm_lapic *apic);
u64 kvm_lapic_get_cr8(struct kvm_vcpu *vcpu);
void kvm_lapic_set_tpr(struct kvm_vcpu *vcpu, unsigned long cr8);
diff --git a/drivers/kvm/kvm.h b/drivers/kvm/kvm.h
index dbb929d..5e318b6 100644
--- a/drivers/kvm/kvm.h
+++ b/drivers/kvm/kvm.h
@@ -326,6 +326,13 @@ struct kvm_vcpu {
u64 shadow_efer;
u64 apic_base;
struct kvm_lapic *apic; /* kernel irqchip context */
+#define VCPU_MP_STATE_RUNNABLE 0
+#define VCPU_MP_STATE_UNINITIALIZED 1
+#define VCPU_MP_STATE_INIT_RECEIVED 2
+#define VCPU_MP_STATE_SIPI_RECEIVED 3
+#define VCPU_MP_STATE_HALTED 4
+ int mp_state;
+ int sipi_vector;
u64 ia32_misc_enable_msr;

struct kvm_mmu mmu;
diff --git a/drivers/kvm/kvm_main.c b/drivers/kvm/kvm_main.c
index a25dfc9..f101430 100644
--- a/drivers/kvm/kvm_main.c
+++ b/drivers/kvm/kvm_main.c
@@ -249,6 +249,10 @@ int kvm_vcpu_init(struct kvm_vcpu *vcpu, struct kvm *kvm, unsigned id)
vcpu->mmu.root_hpa = INVALID_PAGE;
vcpu->kvm = kvm;
vcpu->vcpu_id = id;
+ if (!irqchip_in_kernel(kvm) || id == 0)
+ vcpu->mp_state = VCPU_MP_STATE_RUNNABLE;
+ else
+ vcpu->mp_state = VCPU_MP_STATE_UNINITIALIZED;
init_waitqueue_head(&vcpu->wq);

page = alloc_page(GFP_KERNEL | __GFP_ZERO);
@@ -1371,7 +1375,7 @@ EXPORT_SYMBOL_GPL(emulate_instruction);
/*
* The vCPU has executed a HLT instruction with in-kernel mode enabled.
*/
-static void kvm_vcpu_kernel_halt(struct kvm_vcpu *vcpu)
+static void kvm_vcpu_block(struct kvm_vcpu *vcpu)
{
DECLARE_WAITQUEUE(wait, current);

@@ -1380,24 +1384,28 @@ static void kvm_vcpu_kernel_halt(struct kvm_vcpu *vcpu)
/*
* We will block until either an interrupt or a signal wakes us up
*/
- while(!(irqchip_in_kernel(vcpu->kvm) && kvm_cpu_has_interrupt(vcpu))
- && !vcpu->irq_summary
- && !signal_pending(current)) {
+ while (!kvm_cpu_has_interrupt(vcpu)
+ && !signal_pending(current)
+ && vcpu->mp_state != VCPU_MP_STATE_RUNNABLE
+ && vcpu->mp_state != VCPU_MP_STATE_SIPI_RECEIVED) {
set_current_state(TASK_INTERRUPTIBLE);
vcpu_put(vcpu);
schedule();
vcpu_load(vcpu);
}

+ __set_current_state(TASK_RUNNING);
remove_wait_queue(&vcpu->wq, &wait);
- set_current_state(TASK_RUNNING);
}

int kvm_emulate_halt(struct kvm_vcpu *vcpu)
{
++vcpu->stat.halt_exits;
if (irqchip_in_kernel(vcpu->kvm)) {
- kvm_vcpu_kernel_halt(vcpu);
+ vcpu->mp_state = VCPU_MP_STATE_HALTED;
+ kvm_vcpu_block(vcpu);
+ if (vcpu->mp_state != VCPU_MP_STATE_RUNNABLE)
+ return -EINTR;
return 1;
} else {
vcpu->run->exit_reason = KVM_EXIT_HLT;
@@ -2001,6 +2009,12 @@ static int kvm_vcpu_ioctl_run(struct kvm_vcpu *vcpu, struct kvm_run *kvm_run)

vcpu_load(vcpu);

+ if (unlikely(vcpu->mp_state == VCPU_MP_STATE_UNINITIALIZED)) {
+ kvm_vcpu_block(vcpu);
+ vcpu_put(vcpu);
+ return -EAGAIN;
+ }
+
if (vcpu->sigset_active)
sigprocmask(SIG_SETMASK, &vcpu->sigset, &sigsaved);

diff --git a/drivers/kvm/lapic.c b/drivers/kvm/lapic.c
index ca1db38..a190587 100644
--- a/drivers/kvm/lapic.c
+++ b/drivers/kvm/lapic.c
@@ -312,8 +312,8 @@ static int apic_match_dest(struct kvm_vcpu *vcpu, struct kvm_lapic *source,
static int __apic_accept_irq(struct kvm_lapic *apic, int delivery_mode,
int vector, int level, int trig_mode)
{
- int result = 0;
- int orig_irr;
+ int orig_irr, result = 0;
+ struct kvm_vcpu *vcpu = apic->vcpu;

switch (delivery_mode) {
case APIC_DM_FIXED:
@@ -335,7 +335,13 @@ static int __apic_accept_irq(struct kvm_lapic *apic, int delivery_mode,
} else
apic_clear_vector(vector, apic->regs + APIC_TMR);

- kvm_vcpu_kick(apic->vcpu);
+ if (vcpu->mp_state == VCPU_MP_STATE_RUNNABLE)
+ kvm_vcpu_kick(vcpu);
+ else if (vcpu->mp_state == VCPU_MP_STATE_HALTED) {
+ vcpu->mp_state = VCPU_MP_STATE_RUNNABLE;
+ if (waitqueue_active(&vcpu->wq))
+ wake_up_interruptible(&vcpu->wq);
+ }

result = (orig_irr == 0);
break;
@@ -352,11 +358,30 @@ static int __apic_accept_irq(struct kvm_lapic *apic, int delivery_mode,
break;

case APIC_DM_INIT:
- printk(KERN_DEBUG "Ignoring guest INIT\n");
+ if (level) {
+ if (vcpu->mp_state == VCPU_MP_STATE_RUNNABLE)
+ printk(KERN_DEBUG
+ "INIT on a runnable vcpu %d\n",
+ vcpu->vcpu_id);
+ vcpu->mp_state = VCPU_MP_STATE_INIT_RECEIVED;
+ kvm_vcpu_kick(vcpu);
+ } else {
+ printk(KERN_DEBUG
+ "Ignoring de-assert INIT to vcpu %d\n",
+ vcpu->vcpu_id);
+ }
+
break;

case APIC_DM_STARTUP:
- printk(KERN_DEBUG "Ignoring guest STARTUP\n");
+ printk(KERN_DEBUG "SIPI to vcpu %d vector 0x%02x\n",
+ vcpu->vcpu_id, vector);
+ if (vcpu->mp_state == VCPU_MP_STATE_INIT_RECEIVED) {
+ vcpu->sipi_vector = vector;
+ vcpu->mp_state = VCPU_MP_STATE_SIPI_RECEIVED;
+ if (waitqueue_active(&vcpu->wq))
+ wake_up_interruptible(&vcpu->wq);
+ }
break;

default:
@@ -792,7 +817,7 @@ u64 kvm_lapic_get_base(struct kvm_vcpu *vcpu)
}
EXPORT_SYMBOL_GPL(kvm_lapic_get_base);

-static void lapic_reset(struct kvm_vcpu *vcpu)
+void kvm_lapic_reset(struct kvm_vcpu *vcpu)
{
struct kvm_lapic *apic;
int i;
@@ -839,6 +864,7 @@ static void lapic_reset(struct kvm_vcpu *vcpu)
vcpu, kvm_apic_id(apic),
vcpu->apic_base, apic->base_address);
}
+EXPORT_SYMBOL_GPL(kvm_lapic_reset);

int kvm_lapic_enabled(struct kvm_vcpu *vcpu)
{
@@ -867,7 +893,10 @@ static int __apic_timer_fn(struct kvm_lapic *apic)

atomic_inc(&apic->timer.pending);
if (waitqueue_active(q))
+ {
+ apic->vcpu->mp_state = VCPU_MP_STATE_RUNNABLE;
wake_up_interruptible(q);
+ }
if (apic_lvtt_period(apic)) {
result = 1;
apic->timer.dev.expires = ktime_add_ns(
@@ -928,7 +957,7 @@ int kvm_create_lapic(struct kvm_vcpu *vcpu)
apic->base_address = APIC_DEFAULT_PHYS_BASE;
vcpu->apic_base = APIC_DEFAULT_PHYS_BASE;

- lapic_reset(vcpu);
+ kvm_lapic_reset(vcpu);
apic->dev.read = apic_mmio_read;
apic->dev.write = apic_mmio_write;
apic->dev.in_range = apic_mmio_range;
diff --git a/drivers/kvm/vmx.c b/drivers/kvm/vmx.c
index f4618b9..440cacf 100644
--- a/drivers/kvm/vmx.c
+++ b/drivers/kvm/vmx.c
@@ -1412,6 +1412,8 @@ static int vmx_vcpu_setup(struct vcpu_vmx *vmx)
goto out;
}

+ vmx->vcpu.rmode.active = 0;
+
vmx->vcpu.regs[VCPU_REGS_RDX] = get_rdx_init_val();
set_cr8(&vmx->vcpu, 0);
msr = 0xfee00000 | MSR_IA32_APICBASE_ENABLE;
@@ -1425,8 +1427,13 @@ static int vmx_vcpu_setup(struct vcpu_vmx *vmx)
* GUEST_CS_BASE should really be 0xffff0000, but VT vm86 mode
* insists on having GUEST_CS_BASE == GUEST_CS_SELECTOR << 4. Sigh.
*/
- vmcs_write16(GUEST_CS_SELECTOR, 0xf000);
- vmcs_writel(GUEST_CS_BASE, 0x000f0000);
+ if (vmx->vcpu.vcpu_id == 0) {
+ vmcs_write16(GUEST_CS_SELECTOR, 0xf000);
+ vmcs_writel(GUEST_CS_BASE, 0x000f0000);
+ } else {
+ vmcs_write16(GUEST_CS_SELECTOR, vmx->vcpu.sipi_vector << 8);
+ vmcs_writel(GUEST_CS_BASE, vmx->vcpu.sipi_vector << 12);
+ }
vmcs_write32(GUEST_CS_LIMIT, 0xffff);
vmcs_write32(GUEST_CS_AR_BYTES, 0x9b);

@@ -1451,7 +1458,10 @@ static int vmx_vcpu_setup(struct vcpu_vmx *vmx)
vmcs_writel(GUEST_SYSENTER_EIP, 0);

vmcs_writel(GUEST_RFLAGS, 0x02);
- vmcs_writel(GUEST_RIP, 0xfff0);
+ if (vmx->vcpu.vcpu_id == 0)
+ vmcs_writel(GUEST_RIP, 0xfff0);
+ else
+ vmcs_writel(GUEST_RIP, 0);
vmcs_writel(GUEST_RSP, 0);

//todo: dr0 = dr1 = dr2 = dr3 = 0; dr6 = 0xffff0ff0
@@ -2201,6 +2211,14 @@ static int vmx_vcpu_run(struct kvm_vcpu *vcpu, struct kvm_run *kvm_run)
u8 fail;
int r;

+ if (unlikely(vcpu->mp_state == VCPU_MP_STATE_SIPI_RECEIVED)) {
+ printk("vcpu %d received sipi with vector # %x\n",
+ vcpu->vcpu_id, vcpu->sipi_vector);
+ kvm_lapic_reset(vcpu);
+ vmx_vcpu_setup(vmx);
+ vcpu->mp_state = VCPU_MP_STATE_RUNNABLE;
+ }
+
preempted:
if (vcpu->guest_debug.enabled)
kvm_guest_debug_pre(vcpu);
--
1.5.3