Re: [PATCH 10/11] VMX: work around lacking VNMI support

[Gleb Natapov <gleb@qumranet.com>]

On Wed, Sep 24, 2008 at 02:56:40PM +0200, Jan Kiszka wrote:
> > We should do something like this:
> > 
> > diff --git a/arch/x86/kvm/vmx.c b/arch/x86/kvm/vmx.c
> > index 046a91b..860e66d 100644
> > --- a/arch/x86/kvm/vmx.c
> > +++ b/arch/x86/kvm/vmx.c
> > @@ -2826,10 +2826,20 @@ static int handle_task_switch(struct kvm_vcpu *vcpu, struct kvm_run *kvm_run)
> >  	unsigned long exit_qualification;
> >  	u16 tss_selector;
> >  	int reason;
> > +	struct vcpu_vmx *vmx = to_vmx(vcpu);
> >  
> >  	exit_qualification = vmcs_readl(EXIT_QUALIFICATION);
> >  
> >  	reason = (u32)exit_qualification >> 30;
> > +
> > +	if (reason == TASK_SWITCH_GATE && vmx->vcpu.arch.nmi_injected &&
> > +		(vmx->idt_vectoring_info & VECTORING_INFO_VALID_MASK) &&
> > +		(vmx->idt_vectoring_info & VECTORING_INFO_TYPE_MASK) == INTR_TYPE_NMI_INTR) {
> > +		vcpu->arch.nmi_injected = false;
> > +		vmcs_set_bits(GUEST_INTERRUPTIBILITY_INFO,
> > +				      GUEST_INTR_STATE_NMI);
> > +		printk(KERN_DEBUG"NMI cause task switch. No need to reinject\n");
> > +	}
> 
> OK, I just think we are not supposed to set GUEST_INTR_STATE_NMI without
> cpu_has_virtual_nmis(). Otherwise looks reasonable. Have you tested
> this? Does it make your 2003 power-off?
> 
It does power-off, but hands during reboot. Looking at it right now.

--
			Gleb.