Re: [PATCH 07/10] KVM: x86: Avoid NTP frequency skew for KVM clock on 32-bit host

[Paul Durrant]

On 18/04/2024 20:34, David Woodhouse wrote:
> From: David Woodhouse <dwmw@xxxxxxxxxxxx>
>
> 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,
> (well, OK, more than a decade later but clocks are hard), enable it for
> the 32-bit build too so that get_kvmclock_base_ns() can be unaffected by
> NTP sync on 32-bit too.
>
> Signed-off-by: David Woodhouse <dwmw@xxxxxxxxxxxx>
> ---
>   arch/x86/kvm/x86.c | 18 ++++++------------
>   1 file changed, 6 insertions(+), 12 deletions(-)

Reviewed-by: Paul Durrant <paul@xxxxxxx>