Re: [patch 05/21] Xen-paravirt: paravirt_ops: allocate a fixmap slot

Gerd Hoffmann
2007-02-14T08:44:13Z

Dan Hecht wrote:
> Right. But that is only because Xen decides to allocate the page from
> the (machine) physical space, rather than from the pseudo-physical
> space. My question is: why doesn't Xen allocate shared_info from the
> pseudo-physical space?

Historical reasons ...

> If it had, then this page wouldn't need to be
> treated specially. I'm not sure, but I seem to remember on 64-bit
> Xen/XenLinux allocated shared_info from pseudo-physical space already...

Yep, the ia64 port which came later handles some things differently,
specifically some "magic" pages are allocated more clever ;)

Changing that for x86 would break existing guests though.

cheers,
Gerd

--
Gerd Hoffmann <kraxel@suse.de>