Re: [Xen-devel] [PATCH v4 2/3] arm: export platform_op XENPF_settime64

[Daniel De Graaf <dgdegra@xxxxxxxxxxxxx>]

On 16/11/15 08:08, Ian Campbell wrote:
> On Thu, 2015-11-12 at 17:46 +0000, Stefano Stabellini wrote:
> > Call update_domain_wallclock_time at domain initialization.
> > Set time_offset_seconds to the number of seconds between physical boot
> > and domain initialization: it is going to be used to get/set the
> > wallclock time.
> > Add time_offset_seconds to system_time when before calling do_settime,
> > so that system_time actually accounts for all the time in nsec between
> > machine boot and when the wallclock was set.
> >
> > Expose xsm_platform_op to ARM.
> >
> > Signed-off-by: Stefano Stabellini <stefano.stabellini@xxxxxxxxxxxxx>
> Acked-by: Ian Campbell <ian.campbell@xxxxxxxxxx>
>
> An aside:[...]
> @@ -1332,6 +1332,75 @@ static int flask_deassign_dtdevice(struct domain
> > *d, const char *dtpath)
> >   }
> >   #endif /* HAS_PASSTHROUGH && HAS_DEVICE_TREE */
> >
> > +static int flask_platform_op(uint32_t op)
> > +{
> > +    switch ( op )
> > +    {
> > +#ifdef CONFIG_X86
> > +    /* These operations have their own XSM hooks */
> > +    case XENPF_cpu_online:
> > +    case XENPF_cpu_offline:
> > +    case XENPF_cpu_hotadd:
> > +    case XENPF_mem_hotadd:
> > +        return 0;
> Should this not then be an error (e.g. fail closed)?
During the invocation of these operations, two XSM hooks are called: this
one (from above the switch) and the individual hook (inside the switch).
This hook needs to allow access so that the more detailed hook is called.

> Also, although only implemented today for x86 they don't seem inherently
> any more x86 specific than many of the other things below, so maybe the
> ifdef could be ditched?
The #ifdef is there mostly as a failsafe reminder to ensure that the
implementation for other architectures actually calls the same XSM hooks
that the x86 version does.


--
Daniel De Graaf
National Security Agency

_______________________________________________
Xen-devel mailing list
Xen-devel@xxxxxxxxxxxxx
http://lists.xen.org/xen-devel