Re: [PATCH 06/10] x86: jailhouse: Avoid access of unsupported platform resources

From: Thomas Gleixner
Date: Fri Nov 17 2017 - 17:59:59 EST


On Fri, 17 Nov 2017, Thomas Gleixner wrote:
> On Thu, 16 Nov 2017, Jan Kiszka wrote:
>
> > From: Jan Kiszka <jan.kiszka@xxxxxxxxxxx>
> >
> > We don't have CMOS access, thus we can't set the warm-reset vectors in
>
> s/We/A jailhouse cell/ or s/We/A jailhouse guest/
>
> > do_boot_cpu. There is no RTC, thus also no wall clock. Furthermore,
> > there are no ISA IRQs and no PIC. So fill the platform callbacks
> > accordingly.
>
> > +static void jailhouse_get_wallclock(struct timespec *now)
> > +{
> > + memset(now, 0, sizeof(*now));
> > +}
>
> > @@ -1006,7 +1007,8 @@ static int do_boot_cpu(int apicid, int cpu, struct task_struct *idle,
> > * the targeted processor.
> > */
> >
> > - if (get_uv_system_type() != UV_NON_UNIQUE_APIC) {
> > + if (get_uv_system_type() != UV_NON_UNIQUE_APIC &&
> > + !jailhouse_paravirt()) {
> >
> > pr_debug("Setting warm reset code and vector.\n");
>
> Adding more here might justify a function pointer in x86_platform_ops. Not
> sure though, but we have an increasing amount of xen()/kvm()/whatever
> conditionals popping up all over the place. And now you add jailhouse()
> ones :)

Actually we don't want a function pointer as we would need two. A simple
flag would be sufficient.

Thanks,

tglx