diff mbox series

[v13,13/48] KVM: x86: Prepare kvm_hv_flush_tlb() to handle L2's GPAs

Message ID 20221101145426.251680-14-vkuznets@redhat.com
State New
Headers
Series KVM: x86: hyper-v: Fine-grained TLB flush + L2 TLB flush features |

Commit Message

Vitaly Kuznetsov Nov. 1, 2022, 2:53 p.m. UTC 
  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>
Reviewed-by: Sean Christopherson <seanjc@google.com>
Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>
---
 arch/x86/kvm/hyperv.c | 14 ++++++++++++++
 1 file changed, 14 insertions(+)
diff mbox series

Patch

diff --git a/arch/x86/kvm/hyperv.c b/arch/x86/kvm/hyperv.c
index fca9c51891f5..cb145987f5b8 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>
@@ -1908,6 +1909,19 @@  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);
 
+	/*
+	 * 'Slow' hypercall's first parameter is the address in guest's memory
+	 * where hypercall parameters are placed. This is either a GPA or a
+	 * nested GPA when KVM is handling the call from L2 ('direct' TLB
+	 * flush).  Translate the address here so the memory can be uniformly
+	 * read with kvm_read_guest().
+	 */
+	if (!hc->fast && is_guest_mode(vcpu)) {
+		hc->ingpa = translate_nested_gpa(vcpu, hc->ingpa, 0, NULL);
+		if (unlikely(hc->ingpa == INVALID_GPA))
+			return HV_STATUS_INVALID_HYPERCALL_INPUT;
+	}
+
 	if (hc->code == HVCALL_FLUSH_VIRTUAL_ADDRESS_LIST ||
 	    hc->code == HVCALL_FLUSH_VIRTUAL_ADDRESS_SPACE) {
 		if (hc->fast) {