diff options
| -rw-r--r-- | arch/x86/include/asm/kvm_host.h | 1 | ||||
| -rw-r--r-- | arch/x86/kvm/svm.c | 35 | ||||
| -rw-r--r-- | arch/x86/kvm/vmx.c | 24 |
3 files changed, 18 insertions, 42 deletions
diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h index e21aee9..4931415 100644 --- a/arch/x86/include/asm/kvm_host.h +++ b/arch/x86/include/asm/kvm_host.h @@ -130,7 +130,6 @@ enum kvm_reg_ex { VCPU_EXREG_PDPTR = NR_VCPU_REGS, VCPU_EXREG_CR3, VCPU_EXREG_RFLAGS, - VCPU_EXREG_CPL, VCPU_EXREG_SEGMENTS, }; diff --git a/arch/x86/kvm/svm.c b/arch/x86/kvm/svm.c index 0b7d58d..ec8366c 100644 --- a/arch/x86/kvm/svm.c +++ b/arch/x86/kvm/svm.c @@ -1338,21 +1338,6 @@ static void svm_vcpu_put(struct kvm_vcpu *vcpu) wrmsrl(host_save_user_msrs[i], svm->host_user_msrs[i]); } -static void svm_update_cpl(struct kvm_vcpu *vcpu) -{ - struct vcpu_svm *svm = to_svm(vcpu); - int cpl; - - if (!is_protmode(vcpu)) - cpl = 0; - else if (svm->vmcb->save.rflags & X86_EFLAGS_VM) - cpl = 3; - else - cpl = svm->vmcb->save.cs.selector & 0x3; - - svm->vmcb->save.cpl = cpl; -} - static unsigned long svm_get_rflags(struct kvm_vcpu *vcpu) { return to_svm(vcpu)->vmcb->save.rflags; @@ -1360,11 +1345,12 @@ static unsigned long svm_get_rflags(struct kvm_vcpu *vcpu) static void svm_set_rflags(struct kvm_vcpu *vcpu, unsigned long rflags) { - unsigned long old_rflags = to_svm(vcpu)->vmcb->save.rflags; - + /* + * Any change of EFLAGS.VM is accompained by a reload of SS + * (caused by either a task switch or an inter-privilege IRET), + * so we do not need to update the CPL here. + */ to_svm(vcpu)->vmcb->save.rflags = rflags; - if ((old_rflags ^ rflags) & X86_EFLAGS_VM) - svm_update_cpl(vcpu); } static void svm_cache_reg(struct kvm_vcpu *vcpu, enum kvm_reg reg) @@ -1631,8 +1617,15 @@ static void svm_set_segment(struct kvm_vcpu *vcpu, s->attrib |= (var->db & 1) << SVM_SELECTOR_DB_SHIFT; s->attrib |= (var->g & 1) << SVM_SELECTOR_G_SHIFT; } - if (seg == VCPU_SREG_CS) - svm_update_cpl(vcpu); + + /* + * This is always accurate, except if SYSRET returned to a segment + * with SS.DPL != 3. Intel does not have this quirk, and always + * forces SS.DPL to 3 on sysret, so we ignore that case; fixing it + * would entail passing the CPL to userspace and back. + */ + if (seg == VCPU_SREG_SS) + svm->vmcb->save.cpl = (s->attrib >> SVM_SELECTOR_DPL_SHIFT) & 3; mark_dirty(svm->vmcb, VMCB_SEG); } diff --git a/arch/x86/kvm/vmx.c b/arch/x86/kvm/vmx.c index 6f7463f..a267108 100644 --- a/arch/x86/kvm/vmx.c +++ b/arch/x86/kvm/vmx.c @@ -414,7 +414,6 @@ struct vcpu_vmx { struct kvm_vcpu vcpu; unsigned long host_rsp; u8 fail; - u8 cpl; bool nmi_known_unmasked; u32 exit_intr_info; u32 idt_vectoring_info; @@ -3150,10 +3149,6 @@ static void enter_pmode(struct kvm_vcpu *vcpu) fix_pmode_seg(vcpu, VCPU_SREG_DS, &vmx->rmode.segs[VCPU_SREG_DS]); fix_pmode_seg(vcpu, VCPU_SREG_FS, &vmx->rmode.segs[VCPU_SREG_FS]); fix_pmode_seg(vcpu, VCPU_SREG_GS, &vmx->rmode.segs[VCPU_SREG_GS]); - - /* CPL is always 0 when CPU enters protected mode */ - __set_bit(VCPU_EXREG_CPL, (ulong *)&vcpu->arch.regs_avail); - vmx->cpl = 0; } static void fix_rmode_seg(int seg, struct kvm_segment *save) @@ -3555,22 +3550,14 @@ static int vmx_get_cpl(struct kvm_vcpu *vcpu) { struct vcpu_vmx *vmx = to_vmx(vcpu); - if (!is_protmode(vcpu)) + if (unlikely(vmx->rmode.vm86_active)) return 0; - - if (!is_long_mode(vcpu) - && (kvm_get_rflags(vcpu) & X86_EFLAGS_VM)) /* if virtual 8086 */ - return 3; - - if (!test_bit(VCPU_EXREG_CPL, (ulong *)&vcpu->arch.regs_avail)) { - __set_bit(VCPU_EXREG_CPL, (ulong *)&vcpu->arch.regs_avail); - vmx->cpl = vmx_read_guest_seg_selector(vmx, VCPU_SREG_CS) & 3; + else { + int ar = vmx_read_guest_seg_ar(vmx, VCPU_SREG_SS); + return AR_DPL(ar); } - - return vmx->cpl; } - static u32 vmx_segment_access_rights(struct kvm_segment *var) { u32 ar; @@ -3598,8 +3585,6 @@ static void vmx_set_segment(struct kvm_vcpu *vcpu, const struct kvm_vmx_segment_field *sf = &kvm_vmx_segment_fields[seg]; vmx_segment_cache_clear(vmx); - if (seg == VCPU_SREG_CS) - __clear_bit(VCPU_EXREG_CPL, (ulong *)&vcpu->arch.regs_avail); if (vmx->rmode.vm86_active && seg != VCPU_SREG_LDTR) { vmx->rmode.segs[seg] = *var; @@ -7471,7 +7456,6 @@ static void __noclone vmx_vcpu_run(struct kvm_vcpu *vcpu) vcpu->arch.regs_avail = ~((1 << VCPU_REGS_RIP) | (1 << VCPU_REGS_RSP) | (1 << VCPU_EXREG_RFLAGS) - | (1 << VCPU_EXREG_CPL) | (1 << VCPU_EXREG_PDPTR) | (1 << VCPU_EXREG_SEGMENTS) | (1 << VCPU_EXREG_CR3)); |
