2.6.27-stable review patch. If anyone has any objections, please let us know. ------------------ From: Marcelo Tosatti (cherry picked from commit 29415c37f043d1d54dcf356601d738ff6633b72b) The vcpu thread can be preempted after the guest_debug_pre() callback, resulting in invalid debug registers on the new vcpu. Move it inside the non-preemptable section. Signed-off-by: Marcelo Tosatti Signed-off-by: Avi Kivity Signed-off-by: Greg Kroah-Hartman --- arch/x86/kvm/x86.c | 9 ++++----- 1 file changed, 4 insertions(+), 5 deletions(-) --- a/arch/x86/kvm/x86.c +++ b/arch/x86/kvm/x86.c @@ -2839,10 +2839,6 @@ static int __vcpu_run(struct kvm_vcpu *v down_read(&vcpu->kvm->slots_lock); vapic_enter(vcpu); -preempted: - if (vcpu->guest_debug.enabled) - kvm_x86_ops->guest_debug_pre(vcpu); - again: if (vcpu->requests) if (test_and_clear_bit(KVM_REQ_MMU_RELOAD, &vcpu->requests)) @@ -2896,6 +2892,9 @@ again: goto out; } + if (vcpu->guest_debug.enabled) + kvm_x86_ops->guest_debug_pre(vcpu); + vcpu->guest_mode = 1; /* * Make sure that guest_mode assignment won't happen after @@ -2970,7 +2969,7 @@ out: if (r > 0) { kvm_resched(vcpu); down_read(&vcpu->kvm->slots_lock); - goto preempted; + goto again; } post_kvm_run_save(vcpu, kvm_run); -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/