From 4161a569065b17954848069d5209182083ce876b Mon Sep 17 00:00:00 2001 From: Nadav Amit Date: Thu, 17 Jul 2014 01:19:31 +0300 Subject: [PATCH] KVM: x86: emulator injects #DB when RFLAGS.RF is set If the RFLAGS.RF is set, then no #DB should occur on instruction breakpoints. However, the KVM emulator injects #DB regardless to RFLAGS.RF. This patch fixes this behavior. KVM, however, still appears not to update RFLAGS.RF correctly, regardless of this patch. Signed-off-by: Nadav Amit Signed-off-by: Paolo Bonzini --- arch/x86/kvm/x86.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c index 1fd806cb96d4..cc4f65f39b87 100644 --- a/arch/x86/kvm/x86.c +++ b/arch/x86/kvm/x86.c @@ -5158,7 +5158,8 @@ static bool kvm_vcpu_check_breakpoint(struct kvm_vcpu *vcpu, int *r) } } - if (unlikely(vcpu->arch.dr7 & DR7_BP_EN_MASK)) { + if (unlikely(vcpu->arch.dr7 & DR7_BP_EN_MASK) && + !(kvm_get_rflags(vcpu) & X86_EFLAGS_RF)) { dr6 = kvm_vcpu_check_hw_bp(eip, 0, vcpu->arch.dr7, vcpu->arch.db);