From 1051778f6e1e25c1203869586f4431785a35c13c Mon Sep 17 00:00:00 2001 From: Sean Christopherson Date: Tue, 27 Aug 2019 14:40:35 -0700 Subject: KVM: x86: Handle emulation failure directly in kvm_task_switch() Consolidate the reporting of emulation failure into kvm_task_switch() so that it can return EMULATE_USER_EXIT. This helps pave the way for removing EMULATE_FAIL altogether. This also fixes a theoretical bug where task switch interception could suppress an EMULATE_USER_EXIT return. Signed-off-by: Sean Christopherson Signed-off-by: Paolo Bonzini --- arch/x86/kvm/svm.c | 11 ++--------- arch/x86/kvm/vmx/vmx.c | 14 +++----------- arch/x86/kvm/x86.c | 9 ++++++--- 3 files changed, 11 insertions(+), 23 deletions(-) (limited to 'arch/x86') diff --git a/arch/x86/kvm/svm.c b/arch/x86/kvm/svm.c index fc40052fa334..69e53aa3969d 100644 --- a/arch/x86/kvm/svm.c +++ b/arch/x86/kvm/svm.c @@ -3892,17 +3892,10 @@ static int task_switch_interception(struct vcpu_svm *svm) if (int_type != SVM_EXITINTINFO_TYPE_SOFT) int_vec = -1; - if (kvm_task_switch(&svm->vcpu, tss_selector, int_vec, reason, - has_error_code, error_code) == EMULATE_FAIL) - goto fail; - return 1; -fail: - svm->vcpu.run->exit_reason = KVM_EXIT_INTERNAL_ERROR; - svm->vcpu.run->internal.suberror = KVM_INTERNAL_ERROR_EMULATION; - svm->vcpu.run->internal.ndata = 0; - return 0; + return kvm_task_switch(&svm->vcpu, tss_selector, int_vec, reason, + has_error_code, error_code) != EMULATE_USER_EXIT; } static int cpuid_interception(struct vcpu_svm *svm) diff --git a/arch/x86/kvm/vmx/vmx.c b/arch/x86/kvm/vmx/vmx.c index d4371599abe3..498270cfc71d 100644 --- a/arch/x86/kvm/vmx/vmx.c +++ b/arch/x86/kvm/vmx/vmx.c @@ -5074,21 +5074,13 @@ static int handle_task_switch(struct kvm_vcpu *vcpu) type != INTR_TYPE_NMI_INTR)) skip_emulated_instruction(vcpu); - if (kvm_task_switch(vcpu, tss_selector, - type == INTR_TYPE_SOFT_INTR ? idt_index : -1, reason, - has_error_code, error_code) == EMULATE_FAIL) { - vcpu->run->exit_reason = KVM_EXIT_INTERNAL_ERROR; - vcpu->run->internal.suberror = KVM_INTERNAL_ERROR_EMULATION; - vcpu->run->internal.ndata = 0; - return 0; - } - /* * TODO: What about debug traps on tss switch? * Are we supposed to inject them and update dr6? */ - - return 1; + return kvm_task_switch(vcpu, tss_selector, + type == INTR_TYPE_SOFT_INTR ? idt_index : -1, + reason, has_error_code, error_code) != EMULATE_USER_EXIT; } static int handle_ept_violation(struct kvm_vcpu *vcpu) diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c index 802dfb926ca7..bdee7e39accb 100644 --- a/arch/x86/kvm/x86.c +++ b/arch/x86/kvm/x86.c @@ -8693,9 +8693,12 @@ int kvm_task_switch(struct kvm_vcpu *vcpu, u16 tss_selector, int idt_index, ret = emulator_task_switch(ctxt, tss_selector, idt_index, reason, has_error_code, error_code); - - if (ret) - return EMULATE_FAIL; + if (ret) { + vcpu->run->exit_reason = KVM_EXIT_INTERNAL_ERROR; + vcpu->run->internal.suberror = KVM_INTERNAL_ERROR_EMULATION; + vcpu->run->internal.ndata = 0; + return EMULATE_USER_EXIT; + } kvm_rip_write(vcpu, ctxt->eip); kvm_set_rflags(vcpu, ctxt->eflags); -- cgit