Commit 4306f200 authored by Radim Krčmář's avatar Radim Krčmář Committed by Paolo Bonzini
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ptp_kvm: try to detect hypercall availability 



No point in registering the device if it cannot work.
The hypercall does not advertise itself, so we have to call it.

Signed-off-by: default avatarRadim Krčmář <rkrcmar@redhat.com>
Signed-off-by: default avatarPaolo Bonzini <pbonzini@redhat.com>
parent 681bcea8

drivers/ptp/ptp_kvm.c

+7 −0
Original line number Diff line number Diff line
@@ -176,12 +176,19 @@ static void __exit ptp_kvm_exit(void) 


static int __init ptp_kvm_init(void)

{

	long ret;



	clock_pair_gpa = slow_virt_to_phys(&clock_pair);

	hv_clock = pvclock_pvti_cpu0_va();



	if (!hv_clock)

		return -ENODEV;



	ret = kvm_hypercall2(KVM_HC_CLOCK_PAIRING, clock_pair_gpa,

			KVM_CLOCK_PAIRING_WALLCLOCK);

	if (ret == -KVM_ENOSYS || ret == -KVM_EOPNOTSUPP)

		return -ENODEV;



	kvm_ptp_clock.caps = ptp_kvm_caps;



	kvm_ptp_clock.ptp_clock = ptp_clock_register(&kvm_ptp_clock.caps, NULL);