From 03b28f8133165dbe4cd922054d599e26b8119508 Mon Sep 17 00:00:00 2001
From: Jan Kiszka <jan.kiszka@siemens.com>
Date: Mon, 29 Apr 2013 16:46:42 +0200
Subject: [PATCH] KVM: x86: Account for failing enable_irq_window for NMI
window request
With VMX, enable_irq_window can now return -EBUSY, in which case an
immediate exit shall be requested before entering the guest. Account for
this also in enable_nmi_window which uses enable_irq_window in absence
of vnmi support, e.g.
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
---
arch/x86/include/asm/kvm_host.h | 2 +-
arch/x86/kvm/svm.c | 5 +++--
arch/x86/kvm/vmx.c | 16 +++++++---------
arch/x86/kvm/x86.c | 3 ++-
4 files changed, 13 insertions(+), 13 deletions(-)
diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h
index ec14b7245a4e..3741c653767c 100644
--- a/arch/x86/include/asm/kvm_host.h
+++ b/arch/x86/include/asm/kvm_host.h
@@ -695,7 +695,7 @@ struct kvm_x86_ops {
int (*nmi_allowed)(struct kvm_vcpu *vcpu);
bool (*get_nmi_mask)(struct kvm_vcpu *vcpu);
void (*set_nmi_mask)(struct kvm_vcpu *vcpu, bool masked);
- void (*enable_nmi_window)(struct kvm_vcpu *vcpu);
+ int (*enable_nmi_window)(struct kvm_vcpu *vcpu);
int (*enable_irq_window)(struct kvm_vcpu *vcpu);
void (*update_cr8_intercept)(struct kvm_vcpu *vcpu, int tpr, int irr);
int (*vm_has_apicv)(struct kvm *kvm);
diff --git a/arch/x86/kvm/svm.c b/arch/x86/kvm/svm.c
index 7f896cbe717f..3421d5a92c06 100644
--- a/arch/x86/kvm/svm.c
+++ b/arch/x86/kvm/svm.c
@@ -3649,13 +3649,13 @@ static int enable_irq_window(struct kvm_vcpu *vcpu)
return 0;
}
-static void enable_nmi_window(struct kvm_vcpu *vcpu)
+static int enable_nmi_window(struct kvm_vcpu *vcpu)
{
struct vcpu_svm *svm = to_svm(vcpu);
if ((svm->vcpu.arch.hflags & (HF_NMI_MASK | HF_IRET_MASK))
== HF_NMI_MASK)
- return; /* IRET will cause a vm exit */
+ return 0; /* IRET will cause a vm exit */
/*
* Something prevents NMI from been injected. Single step over possible
@@ -3664,6 +3664,7 @@ static void enable_nmi_window(struct kvm_vcpu *vcpu)
svm->nmi_singlestep = true;
svm->vmcb->save.rflags |= (X86_EFLAGS_TF | X86_EFLAGS_RF);
update_db_bp_intercept(vcpu);
+ return 0;
}
static int svm_set_tss_addr(struct kvm *kvm, unsigned int addr)
diff --git a/arch/x86/kvm/vmx.c b/arch/x86/kvm/vmx.c
index e10217e99d2c..e53a5f7aa8a9 100644
--- a/arch/x86/kvm/vmx.c
+++ b/arch/x86/kvm/vmx.c
@@ -4417,22 +4417,20 @@ static int enable_irq_window(struct kvm_vcpu *vcpu)
return 0;
}
-static void enable_nmi_window(struct kvm_vcpu *vcpu)
+static int enable_nmi_window(struct kvm_vcpu *vcpu)
{
u32 cpu_based_vm_exec_control;
- if (!cpu_has_virtual_nmis()) {
- enable_irq_window(vcpu);
- return;
- }
+ if (!cpu_has_virtual_nmis())
+ return enable_irq_window(vcpu);
+
+ if (vmcs_read32(GUEST_INTERRUPTIBILITY_INFO) & GUEST_INTR_STATE_STI)
+ return enable_irq_window(vcpu);
- if (vmcs_read32(GUEST_INTERRUPTIBILITY_INFO) & GUEST_INTR_STATE_STI) {
- enable_irq_window(vcpu);
- return;
- }
cpu_based_vm_exec_control = vmcs_read32(CPU_BASED_VM_EXEC_CONTROL);
cpu_based_vm_exec_control |= CPU_BASED_VIRTUAL_NMI_PENDING;
vmcs_write32(CPU_BASED_VM_EXEC_CONTROL, cpu_based_vm_exec_control);
+ return 0;
}
static void vmx_inject_irq(struct kvm_vcpu *vcpu)
diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index 96f914e828d4..94f35d22c5fb 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -5756,7 +5756,8 @@ static int vcpu_enter_guest(struct kvm_vcpu *vcpu)
/* enable NMI/IRQ window open exits if needed */
if (vcpu->arch.nmi_pending)
- kvm_x86_ops->enable_nmi_window(vcpu);
+ req_immediate_exit =
+ kvm_x86_ops->enable_nmi_window(vcpu) != 0;
else if (kvm_cpu_has_injectable_intr(vcpu) || req_int_win)
req_immediate_exit =
kvm_x86_ops->enable_irq_window(vcpu) != 0;