Re: [Xen-devel] Xen on Seattle

[Suravee Suthikulanit <suravee.suthikulpanit@xxxxxxx>]

On 9/2/2014 1:06 PM, Stefano Stabellini wrote:
> On Tue, 2 Sep 2014, Suravee Suthikulanit wrote:
> > Hi all,
> >
> > I am running into an issue booting Xen on Seattle platform where dom0 kernel
> > failed to make the following hypercall in arch/arm/xen/enlighten.c:
> > xen_percpu_init().
> >
> >   HYPERVISOR_vcpu_op(VCPUOP_register_vcpu_info, cpu, &info)
> >
> > After investigation, the hypercall failed in the xen/common/domain.c:
> > map_vcpu_info(), where it check
> >
> >      if ( offset > (PAGE_SIZE - sizeof(vcpu_info_t)) )
> >          return -EINVAL;
> >
> > Here:
> >
> > (XEN) DEBUG0: map_vcpu_info: offset = 0x6790
> > (XEN) DEBUG0: map_vcpu_info: PAGE_SIZE = 0x1000
> > (XEN) DEBUG0: map_vcpu_info: sizeof(vcpu_info_t) = 0x30
> >
> > If I understand correctly, it seems that the hypervisor is making assumption
> > that the Dom0 guest is using 4K page size.  The PAGE_SHIFT in
> > include/asm-arm/config.h is currently set to 12.  So, I have tried changing
> > this to 16 (for 64K page). However, there is a restriction on the 16-bit value
> > of the struct active_grant_entry { length:16; }. So, I cannot boot dom0 with
> > 64K page size. Is this accurate?
> Hello Suravee,
> yes, that is correct: all pages used in hypercalls and shared with the
> hypervisor need to be 4K pages.
Ok, the next question would be, would it make sense/possible to extend 
the support to allow 64K pages?
Suravee


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