KVM: x86: Avoid NTP frequency skew for KVM clock on 32-bit host

Now that 64-bit KVM doesn't consume pvclock_gtod_data when getting the
kvmclock base, use the ktime_mono_to_any() version on 32-bit hosts so
that they too are unaffected by NPT sync.

Note, even if KVM still used pvclock_gtod_data for getting kvmclock base,
it would still be very doable and reasonable to avoid skew on 32-bit hosts,
it's just much simpler now that KVM uses ktime_mono_to_any().

Specifically, commit 53fafdbb8b21 ("KVM: x86: switch KVMCLOCK base to
monotonic raw clock") did so only for 64-bit hosts, by capturing the boot
offset from within the existing clocksource notifier update_pvclock_gtod().

That notifier was added in commit 16e8d74d2da9 ("KVM: x86: notifier for
clocksource changes") but only on x86_64, because its original purpose
was just to disable the "master clock" mode which is only supported on
x86_64.

Now that the notifier is used for more than disabling master clock mode,
enabling it would be trivial for 32-bit builds as well, but as above,
that's a moot point since get_kvmclock_base_ns() no longer relies on the
notifier.

Signed-off-by: David Woodhouse <dwmw@amazon.co.uk>
Reviewed-by: Paul Durrant <paul@xen.org>
[sean: rebase on top of ktime_mono_to_any() usage]
Link: https://patch.msgid.link/20260826213303.914988-7-seanjc@google.com
Signed-off-by: Sean Christopherson <seanjc@google.com>

0 files changed, 0 insertions, 0 deletions