kvm/x86: Reject Hyper-V hypercall continuation

Currently we do not support Hyper-V hypercall continuation
so reject it.

Signed-off-by: Andrey Smetanin <asmetanin@virtuozzo.com>
Reviewed-by: Roman Kagan <rkagan@virtuozzo.com>
CC: Gleb Natapov <gleb@kernel.org>
CC: Paolo Bonzini <pbonzini@redhat.com>
CC: Joerg Roedel <joro@8bytes.org>
CC: "K. Y. Srinivasan" <kys@microsoft.com>
CC: Haiyang Zhang <haiyangz@microsoft.com>
CC: Roman Kagan <rkagan@virtuozzo.com>
CC: Denis V. Lunev <den@openvz.org>
CC: qemu-devel@nongnu.org
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

diff --git a/arch/x86/kvm/hyperv.c b/arch/x86/kvm/hyperv.c
index 599b067..e8af597 100644 (file)
--- a/arch/x86/kvm/hyperv.c
+++ b/arch/x86/kvm/hyperv.c
@@ -1083,6 +1083,12 @@ int kvm_hv_hypercall(struct kvm_vcpu *vcpu)
 
        trace_kvm_hv_hypercall(code, fast, rep_cnt, rep_idx, ingpa, outgpa);
 
+       /* Hypercall continuation is not supported yet */
+       if (rep_cnt || rep_idx) {
+               res = HV_STATUS_INVALID_HYPERCALL_CODE;
+               goto set_result;
+       }
+
        switch (code) {
        case HVCALL_NOTIFY_LONG_SPIN_WAIT:
                kvm_vcpu_on_spin(vcpu);
@@ -1092,6 +1098,7 @@ int kvm_hv_hypercall(struct kvm_vcpu *vcpu)
                break;
        }
 
+set_result:
        ret = res | (((u64)rep_done & 0xfff) << 32);
        if (longmode) {
                kvm_register_write(vcpu, VCPU_REGS_RAX, ret);