Re: [PATCH v3 1/5] xen: introduce xen,enhanced dom0less property

[Stefano Stabellini <sstabellini@xxxxxxxxxx>]

On Sat, 29 Jan 2022, Julien Grall wrote:
> > diff --git a/xen/arch/arm/domain_build.c b/xen/arch/arm/domain_build.c
> > index 6931c022a2..9144d6c0b6 100644
> > --- a/xen/arch/arm/domain_build.c
> > +++ b/xen/arch/arm/domain_build.c
> > @@ -2963,6 +2963,7 @@ static int __init construct_domU(struct domain *d,
> >                                    const struct dt_device_node *node)
> >   {
> >       struct kernel_info kinfo = {};
> > +    const char *dom0less_enhanced;
> >       int rc;
> >       u64 mem;
> >   @@ -2978,6 +2979,12 @@ static int __init construct_domU(struct domain *d,
> >         kinfo.vpl011 = dt_property_read_bool(node, "vpl011");
> >   +    rc = dt_property_read_string(node, "xen,enhanced",
> > &dom0less_enhanced);
> > +    if ( rc == -EILSEQ ||
> 
> I think the use an -EILSEQ wants an explanation. In a previous version, you
> wrote that the value would be returned when:
> 
> fdt set /chosen/domU0 xen,enhanced
> 
> But it is not clear why. Can you print pp->value, pp->length, strnlen(..) when
> this happens?

I added in dt_property_read_string:

printk("DEBUG %s %d value=%s value[0]=%d length=%u 
len=%lu\n",__func__,__LINE__,(char*)pp->value, *((char*)pp->value),pp->length, 
strlen(pp->value));

This is the output:
(XEN) DEBUG dt_property_read_string 205 value= value[0]=0 length=0 len=0