Re: [PATCH v3 06/34] KVM: x86: Prepare kvm_hv_flush_tlb() to handle L2's GPAs

[Maxim Levitsky]

On Thu, 2022-04-14 at 15:19 +0200, Vitaly Kuznetsov wrote:
> To handle L2 TLB flush requests, KVM needs to translate the specified
> L2 GPA to L1 GPA to read hypercall arguments from there.
> 
> No fucntional change as KVM doesn't handle VMCALL/VMMCALL from L2 yet.
   ^ typo
> 
> Signed-off-by: Vitaly Kuznetsov <vkuznets@xxxxxxxxxx>
> ---
>  arch/x86/kvm/hyperv.c | 7 +++++++
>  1 file changed, 7 insertions(+)
> 
> diff --git a/arch/x86/kvm/hyperv.c b/arch/x86/kvm/hyperv.c
> index 1a6f9628cee9..fc4bb0ead9fa 100644
> --- a/arch/x86/kvm/hyperv.c
> +++ b/arch/x86/kvm/hyperv.c
> @@ -23,6 +23,7 @@
>  #include "ioapic.h"
>  #include "cpuid.h"
>  #include "hyperv.h"
> +#include "mmu.h"
>  #include "xen.h"
>  
>  #include <linux/cpu.h>
> @@ -1975,6 +1976,12 @@ static u64 kvm_hv_flush_tlb(struct kvm_vcpu *vcpu, struct kvm_hv_hcall *hc)
>  	 */
>  	BUILD_BUG_ON(KVM_HV_MAX_SPARSE_VCPU_SET_BITS > 64);
>  
> +	if (!hc->fast && is_guest_mode(vcpu)) {
> +		hc->ingpa = translate_nested_gpa(vcpu, hc->ingpa, 0, NULL);
> +		if (unlikely(hc->ingpa == UNMAPPED_GVA))
> +			return HV_STATUS_INVALID_HYPERCALL_INPUT;
> +	}
> +
>  	if (hc->code == HVCALL_FLUSH_VIRTUAL_ADDRESS_LIST ||
>  	    hc->code == HVCALL_FLUSH_VIRTUAL_ADDRESS_SPACE) {
>  		if (hc->fast) {


Reviewed-by: Maxim Levitsky <mlevitsk@xxxxxxxxxx>

Best regards,
	Maxim Levitsky