[PATCH v2] qemu: Do not silently allow non-available timers on non-x86 systems

[Thomas Huth]

On 05/08/2020 12.22, Thomas Huth wrote:
> libvirt currently silently allows <timer name="kvmclock"/> and some
> other timer tags in the guest XML definition for timers that do not
> exist on non-x86 systems. We should not silently ignore these tags
> since the users might not get what they expected otherwise.
> Note: The error is only generated if the timer is marked with
> present="yes" - otherwise we would suddenly refuse XML definitions
> that worked without problems before.
> 
> Buglink: https://bugzilla.redhat.com/show_bug.cgi?id=1754887
> Signed-off-by: Thomas Huth <thuth at redhat.com>
> ---
>  v2: Check also for timer->present == 1
> 
>  src/qemu/qemu_validate.c | 12 ++++++++++++
>  1 file changed, 12 insertions(+)
> 
> diff --git a/src/qemu/qemu_validate.c b/src/qemu/qemu_validate.c
> index 488f258d00..561e7b12c7 100644
> --- a/src/qemu/qemu_validate.c
> +++ b/src/qemu/qemu_validate.c
> @@ -371,6 +371,18 @@ qemuValidateDomainDefClockTimers(const virDomainDef *def,
>          case VIR_DOMAIN_TIMER_NAME_TSC:
>          case VIR_DOMAIN_TIMER_NAME_KVMCLOCK:
>          case VIR_DOMAIN_TIMER_NAME_HYPERVCLOCK:
> +            if (!ARCH_IS_X86(def->os.arch) && timer->present == 1) {
> +                virReportError(VIR_ERR_CONFIG_UNSUPPORTED,
> +                               _("Configuring the '%s' timer is not supported "
> +                                 "for virtType=%s arch=%s machine=%s guests"),
> +                               virDomainTimerNameTypeToString(timer->name),
> +                               virDomainVirtTypeToString(def->virtType),
> +                               virArchToString(def->os.arch),
> +                               def->os.machine);
> +                return -1;
> +            }
> +            break;
> +
>          case VIR_DOMAIN_TIMER_NAME_LAST:
>              break;

Ping! The patch got two Reviewed-bys, so I guess it should be fine now?
Could somebody please pick it up?

Thanks,
 Thomas