From 9c8cba3761d4741cfd53ecc40604fac01f52128a Mon Sep 17 00:00:00 2001 From: Avi Kivity Date: Thu, 22 Nov 2007 11:42:59 +0200 Subject: [PATCH] KVM: Fix faults during injection of real-mode interrupts If vmx fails to inject a real-mode interrupt while fetching the interrupt redirection table, it fails to record this in the vectoring information field. So we detect this condition and do it ourselves. Signed-off-by: Avi Kivity --- drivers/kvm/vmx.c | 51 +++++++++++++++++++++++++++++++++++++++++++++++++-- 1 file changed, 49 insertions(+), 2 deletions(-) diff --git a/drivers/kvm/vmx.c b/drivers/kvm/vmx.c index f045f40..26719aa 100644 --- a/drivers/kvm/vmx.c +++ b/drivers/kvm/vmx.c @@ -65,7 +65,13 @@ struct vcpu_vmx { int fs_reload_needed; int guest_efer_loaded; } host_state; - + struct { + struct { + bool pending; + u8 vector; + unsigned rip; + } irq; + } rmode; }; static inline struct vcpu_vmx *to_vmx(struct kvm_vcpu *vcpu) @@ -1713,11 +1719,16 @@ out: static void vmx_inject_irq(struct kvm_vcpu *vcpu, int irq) { + struct vcpu_vmx *vmx = to_vmx(vcpu); + if (vcpu->rmode.active) { + vmx->rmode.irq.pending = true; + vmx->rmode.irq.vector = irq; + vmx->rmode.irq.rip = vmcs_readl(GUEST_RIP); vmcs_write32(VM_ENTRY_INTR_INFO_FIELD, irq | INTR_TYPE_SOFT_INTR | INTR_INFO_VALID_MASK); vmcs_write32(VM_ENTRY_INSTRUCTION_LEN, 1); - vmcs_writel(GUEST_RIP, vmcs_readl(GUEST_RIP) - 1); + vmcs_writel(GUEST_RIP, vmx->rmode.irq.rip - 1); return; } vmcs_write32(VM_ENTRY_INTR_INFO_FIELD, @@ -2251,6 +2262,17 @@ static void vmx_intr_assist(struct kvm_vcpu *vcpu) return; } if (unlikely(idtv_info_field & INTR_INFO_VALID_MASK)) { + if ((idtv_info_field & VECTORING_INFO_TYPE_MASK) + == INTR_TYPE_EXT_INTR + && vcpu->rmode.active) { + u8 vect = idtv_info_field & VECTORING_INFO_VECTOR_MASK; + + vmx_inject_irq(vcpu, vect); + if (unlikely(has_ext_irq)) + enable_irq_window(vcpu); + return; + } + vmcs_write32(VM_ENTRY_INTR_INFO_FIELD, idtv_info_field); vmcs_write32(VM_ENTRY_INSTRUCTION_LEN, vmcs_read32(VM_EXIT_INSTRUCTION_LEN)); @@ -2275,6 +2297,29 @@ static void vmx_intr_assist(struct kvm_vcpu *vcpu) enable_irq_window(vcpu); } +/* + * 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) +{ + vmx->rmode.irq.pending = 0; + if (vmcs_readl(GUEST_RIP) + 1 != vmx->rmode.irq.rip) + return; + vmcs_writel(GUEST_RIP, vmx->rmode.irq.rip); + if (vmx->idt_vectoring_info & VECTORING_INFO_VALID_MASK) { + vmx->idt_vectoring_info &= ~VECTORING_INFO_TYPE_MASK; + vmx->idt_vectoring_info |= INTR_TYPE_EXT_INTR; + return; + } + vmx->idt_vectoring_info = + VECTORING_INFO_VALID_MASK + | INTR_TYPE_EXT_INTR + | vmx->rmode.irq.vector; +} + static void vmx_vcpu_run(struct kvm_vcpu *vcpu, struct kvm_run *kvm_run) { struct vcpu_vmx *vmx = to_vmx(vcpu); @@ -2401,6 +2446,8 @@ static void vmx_vcpu_run(struct kvm_vcpu *vcpu, struct kvm_run *kvm_run) ); vmx->idt_vectoring_info = vmcs_read32(IDT_VECTORING_INFO_FIELD); + if (vmx->rmode.irq.pending) + fixup_rmode_irq(vmx); vcpu->interrupt_window_open = (vmcs_read32(GUEST_INTERRUPTIBILITY_INFO) & 3) == 0; -- 2.7.4