Commit 2e2f1e8d authored by Vitaly Kuznetsov's avatar Vitaly Kuznetsov Committed by Paolo Bonzini
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KVM: x86: hyper-v: Check access to hypercall before reading XMM registers 



In case guest doesn't have access to the particular hypercall we can avoid
reading XMM registers.

Signed-off-by: default avatarVitaly Kuznetsov <vkuznets@redhat.com>
Reviewed-by: default avatarSiddharth Chandrasekaran <sidcha@amazon.de>
Signed-off-by: default avatarPaolo Bonzini <pbonzini@redhat.com>
Message-Id: <20210730122625.112848-2-vkuznets@redhat.com>
Signed-off-by: default avatarPaolo Bonzini <pbonzini@redhat.com>
parent fa7a549d

arch/x86/kvm/hyperv.c

+3 −3
Original line number Diff line number Diff line
@@ -2173,9 +2173,6 @@ int kvm_hv_hypercall(struct kvm_vcpu *vcpu) 
	hc.rep_idx = (hc.param >> HV_HYPERCALL_REP_START_OFFSET) & 0xfff;

	hc.rep = !!(hc.rep_cnt || hc.rep_idx);



	if (hc.fast && is_xmm_fast_hypercall(&hc))

		kvm_hv_hypercall_read_xmm(&hc);



	trace_kvm_hv_hypercall(hc.code, hc.fast, hc.rep_cnt, hc.rep_idx,

			       hc.ingpa, hc.outgpa);
@@ -2184,6 +2181,9 @@ int kvm_hv_hypercall(struct kvm_vcpu *vcpu) 
		goto hypercall_complete;

	}



	if (hc.fast && is_xmm_fast_hypercall(&hc))

		kvm_hv_hypercall_read_xmm(&hc);



	switch (hc.code) {

	case HVCALL_NOTIFY_LONG_SPIN_WAIT:

		if (unlikely(hc.rep)) {