KVM: x86: Drop RF manipulation for guest single-stepping
authorJan Kiszka <jan.kiszka@siemens.com>
Tue, 23 Feb 2010 16:47:58 +0000 (17:47 +0100)
committerAvi Kivity <avi@redhat.com>
Sun, 25 Apr 2010 10:52:51 +0000 (13:52 +0300)
RF is not required for injecting TF as the latter will trigger only
after an instruction execution anyway. So do not touch RF when arming or
disarming guest single-step mode.

Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
arch/x86/kvm/x86.c

index f2f246ae4a4cee02f3f088735fb2cb0cf1fabb10..a519fc6ed05131fc03b09cd6b6c804460efa03c7 100644 (file)
@@ -5884,7 +5884,7 @@ unsigned long kvm_get_rflags(struct kvm_vcpu *vcpu)
 
        rflags = kvm_x86_ops->get_rflags(vcpu);
        if (vcpu->guest_debug & KVM_GUESTDBG_SINGLESTEP)
-               rflags &= ~(unsigned long)(X86_EFLAGS_TF | X86_EFLAGS_RF);
+               rflags &= ~X86_EFLAGS_TF;
        return rflags;
 }
 EXPORT_SYMBOL_GPL(kvm_get_rflags);
@@ -5893,7 +5893,7 @@ void kvm_set_rflags(struct kvm_vcpu *vcpu, unsigned long rflags)
 {
        if (vcpu->guest_debug & KVM_GUESTDBG_SINGLESTEP &&
            kvm_is_linear_rip(vcpu, vcpu->arch.singlestep_rip))
-               rflags |= X86_EFLAGS_TF | X86_EFLAGS_RF;
+               rflags |= X86_EFLAGS_TF;
        kvm_x86_ops->set_rflags(vcpu, rflags);
 }
 EXPORT_SYMBOL_GPL(kvm_set_rflags);