From 1f3141e80b149e7215313dff29e9a0c47811b1d1 Mon Sep 17 00:00:00 2001 From: Gleb Natapov Date: Mon, 21 Jan 2013 15:36:41 +0200 Subject: [PATCH] KVM: VMX: remove special CPL cache access during transition to real mode. Since vmx_get_cpl() always returns 0 when VCPU is in real mode it is no longer needed. Also reset CPL cache to zero during transaction to protected mode since transaction may happen while CS.selectors & 3 != 0, but in reality CPL is 0. Signed-off-by: Gleb Natapov Signed-off-by: Marcelo Tosatti --- arch/x86/kvm/vmx.c | 12 ++++-------- 1 file changed, 4 insertions(+), 8 deletions(-) diff --git a/arch/x86/kvm/vmx.c b/arch/x86/kvm/vmx.c index dd2a85c..9d2ec88 100644 --- a/arch/x86/kvm/vmx.c +++ b/arch/x86/kvm/vmx.c @@ -2817,6 +2817,10 @@ static void enter_pmode(struct kvm_vcpu *vcpu) fix_pmode_dataseg(vcpu, VCPU_SREG_DS, &vmx->rmode.segs[VCPU_SREG_DS]); fix_pmode_dataseg(vcpu, VCPU_SREG_FS, &vmx->rmode.segs[VCPU_SREG_FS]); fix_pmode_dataseg(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 gva_t rmode_tss_base(struct kvm *kvm) @@ -3229,14 +3233,6 @@ static int vmx_get_cpl(struct kvm_vcpu *vcpu) && (kvm_get_rflags(vcpu) & X86_EFLAGS_VM)) /* if virtual 8086 */ return 3; - /* - * If we enter real mode with cs.sel & 3 != 0, the normal CPL calculations - * fail; use the cache instead. - */ - if (unlikely(vmx->emulation_required && emulate_invalid_guest_state)) { - return vmx->cpl; - } - 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; -- 2.7.4