[PATCH 1/3] KVM: x86: Do a KVM_MEMORY_FAULT EXIT when stage-2 fault handler EFAULTs

[Anish Moorthy <amoorthy@google.com>]

Right now userspace just gets a bare EFAULT when the stage-2 fault
handler fails to fault in the relevant page. Set up a memory fault exit
when this happens, which at the very least eases debugging and might
also let userspace decide on/take some specific action other than
crashing the VM.

Signed-off-by: Anish Moorthy <amoorthy@google.com>
---
 arch/x86/kvm/mmu/mmu.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/arch/x86/kvm/mmu/mmu.c b/arch/x86/kvm/mmu/mmu.c
index 901be9e420a4..c22c807696ae 100644
--- a/arch/x86/kvm/mmu/mmu.c
+++ b/arch/x86/kvm/mmu/mmu.c
@@ -3264,6 +3264,7 @@ static int kvm_handle_error_pfn(struct kvm_vcpu *vcpu, struct kvm_page_fault *fa
 		return RET_PF_RETRY;
 	}
 
+	kvm_mmu_prepare_memory_fault_exit(vcpu, fault);
 	return -EFAULT;
 }
 
-- 
2.46.0.rc2.264.g509ed76dc8-goog