[PATCH 3/4] KVM: VMX: Emulated real mode interrupt injection

Avi Kivity
2010-09-19T12:34:11Z

From: Mohammed Gamal <m.gamal005@gmail.com>

Replace the inject-as-software-interrupt hack we currently have with
emulated injection.

Signed-off-by: Mohammed Gamal <m.gamal005@gmail.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
---
arch/x86/kvm/vmx.c | 65 ++++-----------------------------------------------
1 files changed, 6 insertions(+), 59 deletions(-)

diff --git a/arch/x86/kvm/vmx.c b/arch/x86/kvm/vmx.c
index 8ef6199..2572153 100644
--- a/arch/x86/kvm/vmx.c
+++ b/arch/x86/kvm/vmx.c
@@ -155,11 +155,6 @@ struct vcpu_vmx {
u32 limit;
u32 ar;
} tr, es, ds, fs, gs;
- struct {
- bool pending;
- u8 vector;
- unsigned rip;
- } irq;
} rmode;
int vpid;
bool emulation_required;
@@ -1034,16 +1029,8 @@ static void vmx_queue_exception(struct kvm_vcpu *vcpu, unsigned nr,
}

if (vmx->rmode.vm86_active) {
- vmx->rmode.irq.pending = true;
- vmx->rmode.irq.vector = nr;
- vmx->rmode.irq.rip = kvm_rip_read(vcpu);
- if (kvm_exception_is_soft(nr))
- vmx->rmode.irq.rip +=
- vmx->vcpu.arch.event_exit_inst_len;
- intr_info |= INTR_TYPE_SOFT_INTR;
- vmcs_write32(VM_ENTRY_INTR_INFO_FIELD, intr_info);
- vmcs_write32(VM_ENTRY_INSTRUCTION_LEN, 1);
- kvm_rip_write(vcpu, vmx->rmode.irq.rip - 1);
+ if (kvm_inject_realmode_interrupt(vcpu, nr) != EMULATE_DONE)
+ kvm_make_request(KVM_REQ_TRIPLE_FAULT, vcpu);
return;
}

@@ -2822,16 +2809,8 @@ static void vmx_inject_irq(struct kvm_vcpu *vcpu)

++vcpu->stat.irq_injections;
if (vmx->rmode.vm86_active) {
- vmx->rmode.irq.pending = true;
- vmx->rmode.irq.vector = irq;
- vmx->rmode.irq.rip = kvm_rip_read(vcpu);
- if (vcpu->arch.interrupt.soft)
- vmx->rmode.irq.rip +=
- vmx->vcpu.arch.event_exit_inst_len;
- vmcs_write32(VM_ENTRY_INTR_INFO_FIELD,
- irq | INTR_TYPE_SOFT_INTR | INTR_INFO_VALID_MASK);
- vmcs_write32(VM_ENTRY_INSTRUCTION_LEN, 1);
- kvm_rip_write(vcpu, vmx->rmode.irq.rip - 1);
+ if (kvm_inject_realmode_interrupt(vcpu, irq) != EMULATE_DONE)
+ kvm_make_request(KVM_REQ_TRIPLE_FAULT, vcpu);
return;
}
intr = irq | INTR_INFO_VALID_MASK;
@@ -2863,14 +2842,8 @@ static void vmx_inject_nmi(struct kvm_vcpu *vcpu)

++vcpu->stat.nmi_injections;
if (vmx->rmode.vm86_active) {
- vmx->rmode.irq.pending = true;
- vmx->rmode.irq.vector = NMI_VECTOR;
- vmx->rmode.irq.rip = kvm_rip_read(vcpu);
- vmcs_write32(VM_ENTRY_INTR_INFO_FIELD,
- NMI_VECTOR | INTR_TYPE_SOFT_INTR |
- INTR_INFO_VALID_MASK);
- vmcs_write32(VM_ENTRY_INSTRUCTION_LEN, 1);
- kvm_rip_write(vcpu, vmx->rmode.irq.rip - 1);
+ if (kvm_inject_realmode_interrupt(vcpu, NMI_VECTOR) != EMULATE_DONE)
+ kvm_make_request(KVM_REQ_TRIPLE_FAULT, vcpu);
return;
}
vmcs_write32(VM_ENTRY_INTR_INFO_FIELD,
@@ -3832,29 +3805,6 @@ static void vmx_recover_nmi_blocking(struct vcpu_vmx *vmx)
ktime_to_ns(ktime_sub(ktime_get(), vmx->entry_time));
}

-/*
- * Failure to inject an interrupt should give us the information
- * in IDT_VECTORING_INFO_FIELD. However, if the failure occurs
- * when fetching the interrupt redirection bitmap in the real-mode
- * tss, this doesn't happen. So we do it ourselves.
- */
-static void fixup_rmode_irq(struct vcpu_vmx *vmx, u32 *idt_vectoring_info)
-{
- vmx->rmode.irq.pending = 0;
- if (kvm_rip_read(&vmx->vcpu) + 1 != vmx->rmode.irq.rip)
- return;
- kvm_rip_write(&vmx->vcpu, vmx->rmode.irq.rip);
- if (*idt_vectoring_info & VECTORING_INFO_VALID_MASK) {
- *idt_vectoring_info &= ~VECTORING_INFO_TYPE_MASK;
- *idt_vectoring_info |= INTR_TYPE_EXT_INTR;
- return;
- }
- *idt_vectoring_info =
- VECTORING_INFO_VALID_MASK
- | INTR_TYPE_EXT_INTR
- | vmx->rmode.irq.vector;
-}
-
static void __vmx_complete_interrupts(struct vcpu_vmx *vmx,
u32 idt_vectoring_info,
int instr_len_field,
@@ -3864,9 +3814,6 @@ static void __vmx_complete_interrupts(struct vcpu_vmx *vmx,
int type;
bool idtv_info_valid;

- if (vmx->rmode.irq.pending)
- fixup_rmode_irq(vmx, &idt_vectoring_info);
-
idtv_info_valid = idt_vectoring_info & VECTORING_INFO_VALID_MASK;

vmx->vcpu.arch.nmi_injected = false;
--
1.7.2.3