Since the pv_apic_ops are only present if CONFIG_X86_LOCAL_APIC is compiled
in, kvmclock failed to build without this option.  This patch fixes this.
Signed-off-by: NGlauber Costa <gcosta@redhat.com>
Signed-off-by: NAvi Kivity <avi@qumranet.com>

This patch writes 0 (actually, what really matters is that the
LSB is cleared) to the system time msr before shutting down
the machine for kexec.

Without it, we can have a random memory location being written
when the guest comes back

It overrides the functions shutdown, used in the path of kernel_kexec() (sys.c)
and crash_shutdown, used in the path of crash_kexec() (kexec.c)
Signed-off-by: NGlauber Costa <gcosta@redhat.com>
Signed-off-by: NAvi Kivity <avi@qumranet.com>

This is the guest part of kvm clock implementation
It does not do tsc-only timing, as tsc can have deltas
between cpus, and it did not seem worthy to me to keep
adjusting them.

We do use it, however, for fine-grained adjustment.

Other than that, time comes from the host.

[randy dunlap: add missing include]
[randy dunlap: disallow on Voyager or Visual WS]
Signed-off-by: NGlauber de Oliveira Costa <gcosta@redhat.com>
Signed-off-by: NRandy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: NAvi Kivity <avi@qumranet.com>