From f2483415293b180945da707e7dbe74e5daa72651 Mon Sep 17 00:00:00 2001 From: Jan Kiszka Date: Wed, 20 Jan 2010 18:20:20 +0100 Subject: [PATCH] KVM: VMX: Fix exceptions of mov to dr Injecting GP without an error code is a bad idea (causes unhandled guest exits). Moreover, we must not skip the instruction if we injected an exception. Signed-off-by: Jan Kiszka Signed-off-by: Marcelo Tosatti --- arch/x86/kvm/vmx.c | 13 ++++++++----- 1 file changed, 8 insertions(+), 5 deletions(-) diff --git a/arch/x86/kvm/vmx.c b/arch/x86/kvm/vmx.c index 516084f..9727773 100644 --- a/arch/x86/kvm/vmx.c +++ b/arch/x86/kvm/vmx.c @@ -3045,6 +3045,7 @@ static int handle_dr(struct kvm_vcpu *vcpu) unsigned long val; int dr, reg; + /* Do not handle if the CPL > 0, will trigger GP on re-entry */ if (!kvm_require_cpl(vcpu, 0)) return 1; dr = vmcs_readl(GUEST_DR7); @@ -3099,20 +3100,22 @@ static int handle_dr(struct kvm_vcpu *vcpu) vcpu->arch.eff_db[dr] = val; break; case 4 ... 5: - if (kvm_read_cr4_bits(vcpu, X86_CR4_DE)) + if (kvm_read_cr4_bits(vcpu, X86_CR4_DE)) { kvm_queue_exception(vcpu, UD_VECTOR); + return 1; + } break; case 6: if (val & 0xffffffff00000000ULL) { - kvm_queue_exception(vcpu, GP_VECTOR); - break; + kvm_inject_gp(vcpu, 0); + return 1; } vcpu->arch.dr6 = (val & DR6_VOLATILE) | DR6_FIXED_1; break; case 7: if (val & 0xffffffff00000000ULL) { - kvm_queue_exception(vcpu, GP_VECTOR); - break; + kvm_inject_gp(vcpu, 0); + return 1; } vcpu->arch.dr7 = (val & DR7_VOLATILE) | DR7_FIXED_1; if (!(vcpu->guest_debug & KVM_GUESTDBG_USE_HW_BP)) { -- 1.8.2.3