Re: [Xen-devel] [PATCH v2 10/18] xen: setup hypercall page for PVH

[Roger Pau Monné]

On Tue, Oct 09, 2018 at 01:03:09PM +0200, Juergen Gross wrote:
> Add the needed code to setup the hypercall page for calling into the
> Xen hypervisor.
> 
> Signed-off-by: Juergen Gross <address@hidden>
> ---
>  grub-core/kern/i386/xen/pvh.c | 70 
> +++++++++++++++++++++++++++++++++++++++++++
>  1 file changed, 70 insertions(+)
> 
> diff --git a/grub-core/kern/i386/xen/pvh.c b/grub-core/kern/i386/xen/pvh.c
> index 182ef95f9..c1b1cf8db 100644
> --- a/grub-core/kern/i386/xen/pvh.c
> +++ b/grub-core/kern/i386/xen/pvh.c
> @@ -20,14 +20,84 @@
>  #include <grub/misc.h>
>  #include <grub/memory.h>
>  #include <grub/mm.h>
> +#include <grub/i386/cpuid.h>
>  #include <grub/xen.h>
>  #include <grub/machine/kernel.h>
>  
>  grub_uint64_t grub_rsdp_addr;
>  
> +static struct { char _entry[32]; } hypercall_page[128]
> +  __attribute__ ((aligned (GRUB_XEN_PAGE_SIZE)));
> +
> +static grub_uint32_t xen_cpuid_base;
> +
> +static void
> +grub_xen_early_halt (void)

I would rename this to grub_xen_early_crash

> +{

And you can use the 0xe9 IO port to print a crash debug message even
before initializing the hypercall page, I think this would be helpful
here.

Roger.