Re: [PATCH v13 08/12] KVM: x86: Add Intel PT context switch for each vcpu

[Alexander Shishkin]

Luwei Kang <luwei.kang@xxxxxxxxx> writes:

> +static void pt_guest_enter(struct vcpu_vmx *vmx)
> +{
> +	if (pt_mode == PT_MODE_SYSTEM)
> +		return;
> +
> +	/* Save host state before VM entry */
> +	rdmsrl(MSR_IA32_RTIT_CTL, vmx->pt_desc.host.ctl);
> +
> +	/*
> +	 * Set guest state of MSR_IA32_RTIT_CTL MSR (PT will be disabled
> +	 * on VM entry when it has been disabled in guest before).
> +	 */
> +	vmcs_write64(GUEST_IA32_RTIT_CTL, vmx->pt_desc.guest.ctl);
> +
> +	if (vmx->pt_desc.guest.ctl & RTIT_CTL_TRACEEN) {
> +		wrmsrl(MSR_IA32_RTIT_CTL, 0);
> +		pt_save_msr(&vmx->pt_desc.host, vmx->pt_desc.addr_range);
> +		pt_load_msr(&vmx->pt_desc.guest, vmx->pt_desc.addr_range);
> +	}
> +}

>From my side this is still a NAK, because [1].

[1] https://marc.info/?l=kvm&m=153847567226248&w=2

Thanks,
--
Alex