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path: root/drivers/kvm/vmx.c
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Diffstat (limited to 'drivers/kvm/vmx.c')
-rw-r--r--drivers/kvm/vmx.c88
1 files changed, 72 insertions, 16 deletions
diff --git a/drivers/kvm/vmx.c b/drivers/kvm/vmx.c
index 2d204fd4597..c55635ddf42 100644
--- a/drivers/kvm/vmx.c
+++ b/drivers/kvm/vmx.c
@@ -263,6 +263,7 @@ static void skip_emulated_instruction(struct kvm_vcpu *vcpu)
if (interruptibility & 3)
vmcs_write32(GUEST_INTERRUPTIBILITY_INFO,
interruptibility & ~3);
+ vcpu->interrupt_window_open = 1;
}
static void vmx_inject_gp(struct kvm_vcpu *vcpu, unsigned error_code)
@@ -1214,21 +1215,34 @@ static void kvm_do_inject_irq(struct kvm_vcpu *vcpu)
irq | INTR_TYPE_EXT_INTR | INTR_INFO_VALID_MASK);
}
-static void kvm_try_inject_irq(struct kvm_vcpu *vcpu)
+
+static void do_interrupt_requests(struct kvm_vcpu *vcpu,
+ struct kvm_run *kvm_run)
{
- if ((vmcs_readl(GUEST_RFLAGS) & X86_EFLAGS_IF)
- && (vmcs_read32(GUEST_INTERRUPTIBILITY_INFO) & 3) == 0)
+ u32 cpu_based_vm_exec_control;
+
+ vcpu->interrupt_window_open =
+ ((vmcs_readl(GUEST_RFLAGS) & X86_EFLAGS_IF) &&
+ (vmcs_read32(GUEST_INTERRUPTIBILITY_INFO) & 3) == 0);
+
+ if (vcpu->interrupt_window_open &&
+ vcpu->irq_summary &&
+ !(vmcs_read32(VM_ENTRY_INTR_INFO_FIELD) & INTR_INFO_VALID_MASK))
/*
- * Interrupts enabled, and not blocked by sti or mov ss. Good.
+ * If interrupts enabled, and not blocked by sti or mov ss. Good.
*/
kvm_do_inject_irq(vcpu);
- else
+
+ cpu_based_vm_exec_control = vmcs_read32(CPU_BASED_VM_EXEC_CONTROL);
+ if (!vcpu->interrupt_window_open &&
+ (vcpu->irq_summary || kvm_run->request_interrupt_window))
/*
* Interrupts blocked. Wait for unblock.
*/
- vmcs_write32(CPU_BASED_VM_EXEC_CONTROL,
- vmcs_read32(CPU_BASED_VM_EXEC_CONTROL)
- | CPU_BASED_VIRTUAL_INTR_PENDING);
+ cpu_based_vm_exec_control |= CPU_BASED_VIRTUAL_INTR_PENDING;
+ else
+ cpu_based_vm_exec_control &= ~CPU_BASED_VIRTUAL_INTR_PENDING;
+ vmcs_write32(CPU_BASED_VM_EXEC_CONTROL, cpu_based_vm_exec_control);
}
static void kvm_guest_debug_pre(struct kvm_vcpu *vcpu)
@@ -1565,23 +1579,41 @@ static int handle_wrmsr(struct kvm_vcpu *vcpu, struct kvm_run *kvm_run)
return 1;
}
+static void post_kvm_run_save(struct kvm_vcpu *vcpu,
+ struct kvm_run *kvm_run)
+{
+ kvm_run->if_flag = (vmcs_readl(GUEST_RFLAGS) & X86_EFLAGS_IF) != 0;
+ kvm_run->cr8 = vcpu->cr8;
+ kvm_run->apic_base = vcpu->apic_base;
+ kvm_run->ready_for_interrupt_injection = (vcpu->interrupt_window_open &&
+ vcpu->irq_summary == 0);
+}
+
static int handle_interrupt_window(struct kvm_vcpu *vcpu,
struct kvm_run *kvm_run)
{
- /* Turn off interrupt window reporting. */
- vmcs_write32(CPU_BASED_VM_EXEC_CONTROL,
- vmcs_read32(CPU_BASED_VM_EXEC_CONTROL)
- & ~CPU_BASED_VIRTUAL_INTR_PENDING);
+ /*
+ * If the user space waits to inject interrupts, exit as soon as
+ * possible
+ */
+ if (kvm_run->request_interrupt_window &&
+ !vcpu->irq_summary &&
+ (vmcs_readl(GUEST_RFLAGS) & X86_EFLAGS_IF)) {
+ kvm_run->exit_reason = KVM_EXIT_IRQ_WINDOW_OPEN;
+ ++kvm_stat.irq_window_exits;
+ return 0;
+ }
return 1;
}
static int handle_halt(struct kvm_vcpu *vcpu, struct kvm_run *kvm_run)
{
skip_emulated_instruction(vcpu);
- if (vcpu->irq_summary && (vmcs_readl(GUEST_RFLAGS) & X86_EFLAGS_IF))
+ if (vcpu->irq_summary)
return 1;
kvm_run->exit_reason = KVM_EXIT_HLT;
+ ++kvm_stat.halt_exits;
return 0;
}
@@ -1632,6 +1664,21 @@ static int kvm_handle_exit(struct kvm_run *kvm_run, struct kvm_vcpu *vcpu)
return 0;
}
+/*
+ * Check if userspace requested an interrupt window, and that the
+ * interrupt window is open.
+ *
+ * No need to exit to userspace if we already have an interrupt queued.
+ */
+static int dm_request_for_irq_injection(struct kvm_vcpu *vcpu,
+ struct kvm_run *kvm_run)
+{
+ return (!vcpu->irq_summary &&
+ kvm_run->request_interrupt_window &&
+ vcpu->interrupt_window_open &&
+ (vmcs_readl(GUEST_RFLAGS) & X86_EFLAGS_IF));
+}
+
static int vmx_vcpu_run(struct kvm_vcpu *vcpu, struct kvm_run *kvm_run)
{
u8 fail;
@@ -1663,9 +1710,7 @@ again:
vmcs_writel(HOST_GS_BASE, segment_base(gs_sel));
#endif
- if (vcpu->irq_summary &&
- !(vmcs_read32(VM_ENTRY_INTR_INFO_FIELD) & INTR_INFO_VALID_MASK))
- kvm_try_inject_irq(vcpu);
+ do_interrupt_requests(vcpu, kvm_run);
if (vcpu->guest_debug.enabled)
kvm_guest_debug_pre(vcpu);
@@ -1802,6 +1847,7 @@ again:
fx_save(vcpu->guest_fx_image);
fx_restore(vcpu->host_fx_image);
+ vcpu->interrupt_window_open = (vmcs_read32(GUEST_INTERRUPTIBILITY_INFO) & 3) == 0;
#ifndef CONFIG_X86_64
asm ("mov %0, %%ds; mov %0, %%es" : : "r"(__USER_DS));
@@ -1834,12 +1880,22 @@ again:
/* Give scheduler a change to reschedule. */
if (signal_pending(current)) {
++kvm_stat.signal_exits;
+ post_kvm_run_save(vcpu, kvm_run);
+ return -EINTR;
+ }
+
+ if (dm_request_for_irq_injection(vcpu, kvm_run)) {
+ ++kvm_stat.request_irq_exits;
+ post_kvm_run_save(vcpu, kvm_run);
return -EINTR;
}
+
kvm_resched(vcpu);
goto again;
}
}
+
+ post_kvm_run_save(vcpu, kvm_run);
return 0;
}