From b83b1b4104c6821b4fcb38e78fcbbace21038d8c Mon Sep 17 00:00:00 2001 From: "kfraser@localhost.localdomain" Date: Fri, 20 Oct 2006 10:09:55 +0100 Subject: [PATCH] [HVM][SVM] Fix 1/2 to interrupt delivery logic. This patch uses the VINTR intercept to signal the hypervisor when a guest can take an interrupt. When guest's interrupts are masked by EFLAGS.IF or the guests are in an interrupt shadow, we create a 'fake' virtual interrupt to inject while also enabling the VINTR intercept. When the guest _can_ take interrupts, the hypervisor will #VMEXIT on VINTR. The VINTR exit handler then clears the VINTR intercept bit and clears the V_IRQ bit so that svm_intr_assist() can inject a legitimate interrupt. Signed-off-by: Travis Betak Signed-off-by: Wei Huang Signed-off-by: Tom Woller --- xen/arch/x86/hvm/svm/intr.c | 14 ++++++++++++-- xen/arch/x86/hvm/svm/svm.c | 5 +++++ 2 files changed, 17 insertions(+), 2 deletions(-) diff --git a/xen/arch/x86/hvm/svm/intr.c b/xen/arch/x86/hvm/svm/intr.c index 140df0d636..af1b69deb5 100644 --- a/xen/arch/x86/hvm/svm/intr.c +++ b/xen/arch/x86/hvm/svm/intr.c @@ -43,7 +43,7 @@ * to be suitable for SVM. */ -static inline int svm_inject_extint(struct vcpu *v, int trap, int error_code) +static inline int svm_inject_extint(struct vcpu *v, int trap) { struct vmcb_struct *vmcb = v->arch.hvm_svm.vmcb; vintr_t intr; @@ -87,6 +87,16 @@ asmlinkage void svm_intr_assist(void) re_injecting = 1; } + /* + * create a 'fake' virtual interrupt on to intercept as soon + * as the guest _can_ take interrupts + */ + if (irq_masked(vmcb->rflags) || vmcb->interrupt_shadow) { + vmcb->general1_intercepts |= GENERAL1_INTERCEPT_VINTR; + svm_inject_extint(v, 0x0); /* actual vector doesn't really matter */ + return; + } + /* Guest's interrputs masked? */ rflags = vmcb->rflags; if (irq_masked(rflags)) { @@ -146,7 +156,7 @@ asmlinkage void svm_intr_assist(void) } /* let's inject this interrupt */ TRACE_3D(TRC_VMX_INTR, v->domain->domain_id, intr_vector, 0); - svm_inject_extint(v, intr_vector, VMX_DELIVER_NO_ERROR_CODE); + svm_inject_extint(v, intr_vector); hvm_interrupt_post(v, intr_vector, intr_type); break; case APIC_DM_SMI: diff --git a/xen/arch/x86/hvm/svm/svm.c b/xen/arch/x86/hvm/svm/svm.c index 6c78d9986d..4ce428be5e 100644 --- a/xen/arch/x86/hvm/svm/svm.c +++ b/xen/arch/x86/hvm/svm/svm.c @@ -2811,6 +2811,11 @@ asmlinkage void svm_vmexit_handler(struct cpu_user_regs *regs) svm_inject_exception(v, TRAP_double_fault, 1, 0); break; + case VMEXIT_VINTR: + vmcb->vintr.fields.irq = 0; + vmcb->general1_intercepts &= ~GENERAL1_INTERCEPT_VINTR; + break; + case VMEXIT_INTR: break; -- 2.30.2