[Xen-ia64-devel] Re: [PATCH] pv_ops/xen: elf note based xen startup

[Isaku Yamahata <yamahata@xxxxxxxxxxxxx>]

On Tue, May 06, 2008 at 04:37:11PM +0800, He, Qing wrote:
> This patch enables elf note based xen startup for IA-64, which gives the
> kernel an early hint for running on xen instead of relying on psr.cpl.
> It is also an extension for possible support of future hypervisors.

Thank you for the patch.
Basically it looks good, but some comments.

- It looks unnecessary to define PARAVIRT_HYPERVISOR_TYPE_xxx,
  hypervisor_type and hypervisor_setup_hooks array.
  Only just one hook looks necessary.
  Do you intended to use hypervisor type later?
  If so, probably pv_info->name should be used or add a new member
  to pv_info.

  C-like pseudo code:
  head.S  
  void (*paravirt_setup_hook) = NULL
  ...
  _start:

  if (*paravirt_setup_hook != NULL)
    (*paravirt_setup_hook)()
  ...

  xensetup.S
  startup_xen:
  *paravirt_setup_hook = &xen_setup_hook
  ...
  branch _start

  ...
  xen_setup_hook:
  ...

  Thus the weak symbol trick also goes away.

- Please split it into two parts, xen specific part
  (modification to xensetup.S) and common part (modification to head.S).
  If you don't mind, I'll do it keeping your signed off by.

thanks.
-- 
yamahata

_______________________________________________
Xen-ia64-devel mailing list
Xen-ia64-devel@xxxxxxxxxxxxxxxxxxx
http://lists.xensource.com/xen-ia64-devel