From 42cbf06872cc44fb8d2d6665fa6494b5925eaf1c Mon Sep 17 00:00:00 2001 From: Sean Christopherson Date: Tue, 27 Aug 2019 14:40:31 -0700 Subject: [PATCH] KVM: x86: Move #GP injection for VMware into x86_emulate_instruction() Immediately inject a #GP when VMware emulation fails and return EMULATE_DONE instead of propagating EMULATE_FAIL up the stack. This helps pave the way for removing EMULATE_FAIL altogether. Rename EMULTYPE_VMWARE to EMULTYPE_VMWARE_GP to document that the x86 emulator is called to handle VMware #GP interception, e.g. why a #GP is injected on emulation failure for EMULTYPE_VMWARE_GP. Drop EMULTYPE_NO_UD_ON_FAIL as a standalone type. The "no #UD on fail" is used only in the VMWare case and is obsoleted by having the emulator itself reinject #GP. Signed-off-by: Sean Christopherson Reviewed-by: Liran Alon Signed-off-by: Paolo Bonzini --- arch/x86/include/asm/kvm_host.h | 3 +-- arch/x86/kvm/svm.c | 10 ++-------- arch/x86/kvm/vmx/vmx.c | 10 ++-------- arch/x86/kvm/x86.c | 14 +++++++++----- 4 files changed, 14 insertions(+), 23 deletions(-) diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h index 13b35f94dec4..80071d02b87d 100644 --- a/arch/x86/include/asm/kvm_host.h +++ b/arch/x86/include/asm/kvm_host.h @@ -1325,8 +1325,7 @@ enum emulation_result { #define EMULTYPE_TRAP_UD (1 << 1) #define EMULTYPE_SKIP (1 << 2) #define EMULTYPE_ALLOW_RETRY (1 << 3) -#define EMULTYPE_NO_UD_ON_FAIL (1 << 4) -#define EMULTYPE_VMWARE (1 << 5) +#define EMULTYPE_VMWARE_GP (1 << 5) int kvm_emulate_instruction(struct kvm_vcpu *vcpu, int emulation_type); int kvm_emulate_instruction_from_buffer(struct kvm_vcpu *vcpu, void *insn, int insn_len); diff --git a/arch/x86/kvm/svm.c b/arch/x86/kvm/svm.c index 00ec27bc2946..c7aa55e192c0 100644 --- a/arch/x86/kvm/svm.c +++ b/arch/x86/kvm/svm.c @@ -2768,7 +2768,6 @@ static int gp_interception(struct vcpu_svm *svm) { struct kvm_vcpu *vcpu = &svm->vcpu; u32 error_code = svm->vmcb->control.exit_info_1; - int er; WARN_ON_ONCE(!enable_vmware_backdoor); @@ -2780,13 +2779,8 @@ static int gp_interception(struct vcpu_svm *svm) kvm_queue_exception_e(vcpu, GP_VECTOR, error_code); return 1; } - er = kvm_emulate_instruction(vcpu, - EMULTYPE_VMWARE | EMULTYPE_NO_UD_ON_FAIL); - if (er == EMULATE_USER_EXIT) - return 0; - else if (er != EMULATE_DONE) - kvm_queue_exception_e(vcpu, GP_VECTOR, 0); - return 1; + return kvm_emulate_instruction(vcpu, EMULTYPE_VMWARE_GP) != + EMULATE_USER_EXIT; } static bool is_erratum_383(void) diff --git a/arch/x86/kvm/vmx/vmx.c b/arch/x86/kvm/vmx/vmx.c index d1bac3cb2440..d4371599abe3 100644 --- a/arch/x86/kvm/vmx/vmx.c +++ b/arch/x86/kvm/vmx/vmx.c @@ -4522,7 +4522,6 @@ static int handle_exception_nmi(struct kvm_vcpu *vcpu) u32 intr_info, ex_no, error_code; unsigned long cr2, rip, dr6; u32 vect_info; - enum emulation_result er; vect_info = vmx->idt_vectoring_info; intr_info = vmx->exit_intr_info; @@ -4549,13 +4548,8 @@ static int handle_exception_nmi(struct kvm_vcpu *vcpu) kvm_queue_exception_e(vcpu, GP_VECTOR, error_code); return 1; } - er = kvm_emulate_instruction(vcpu, - EMULTYPE_VMWARE | EMULTYPE_NO_UD_ON_FAIL); - if (er == EMULATE_USER_EXIT) - return 0; - else if (er != EMULATE_DONE) - kvm_queue_exception_e(vcpu, GP_VECTOR, 0); - return 1; + return kvm_emulate_instruction(vcpu, EMULTYPE_VMWARE_GP) != + EMULATE_USER_EXIT; } /* diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c index e6063f20259e..09753b699d81 100644 --- a/arch/x86/kvm/x86.c +++ b/arch/x86/kvm/x86.c @@ -6307,8 +6307,10 @@ static int handle_emulation_failure(struct kvm_vcpu *vcpu, int emulation_type) ++vcpu->stat.insn_emulation_fail; trace_kvm_emulate_insn_failed(vcpu); - if (emulation_type & EMULTYPE_NO_UD_ON_FAIL) - return EMULATE_FAIL; + if (emulation_type & EMULTYPE_VMWARE_GP) { + kvm_queue_exception_e(vcpu, GP_VECTOR, 0); + return EMULATE_DONE; + } kvm_queue_exception(vcpu, UD_VECTOR); @@ -6648,9 +6650,11 @@ int x86_emulate_instruction(struct kvm_vcpu *vcpu, } } - if ((emulation_type & EMULTYPE_VMWARE) && - !is_vmware_backdoor_opcode(ctxt)) - return EMULATE_FAIL; + if ((emulation_type & EMULTYPE_VMWARE_GP) && + !is_vmware_backdoor_opcode(ctxt)) { + kvm_queue_exception_e(vcpu, GP_VECTOR, 0); + return EMULATE_DONE; + } if (emulation_type & EMULTYPE_SKIP) { kvm_rip_write(vcpu, ctxt->_eip); -- GitLab