[PATCH v4 07/37] KVM: x86: Prepare kvm_hv_flush_tlb() to handle L2's GPAs

Vitaly Kuznetsov
2022-05-25T09:02:08Z

To handle L2 TLB flush requests, KVM needs to translate the specified
L2 GPA to L1 GPA to read hypercall arguments from there.

No functional change as KVM doesn't handle VMCALL/VMMCALL from L2 yet.

Reviewed-by: Maxim Levitsky <mlevitsk@redhat.com>
Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>
---
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 f491e26ce162..4973a8802e7f 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>
@@ -1917,6 +1918,12 @@ 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) {
--
2.35.3