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

From: Thomas Gleixner
Date: Fri Nov 17 2017 - 17:58:20 EST


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 :)

Thanks,

tglx