lkml.org 
[lkml]   [2007]   [Apr]   [28]   [last100]   RSS Feed
Views: [more markup]  [less markup]  [headers]  [forward] 
 
Messages in this thread
/
From(Eric W. Biederman)
SubjectRe: [PATCH] x86: fix PSE pagetable construction
DateSat, 28 Apr 2007 00:39:22 -0600
Jeremy Fitzhardinge <jeremy@goop.org> writes:

> I don't have any particularly bright ideas, but there is the other idea
> I mentioned.  I could pre-initialize the pagetable with the Xen
> template, but use unconditional calls to set_pte in pagetable_init. 
> However, the init-time xen_set_pte simply refuse to set _PAGE_WRITE on a
> pte which isn't already writable, thereby protecting the RO state of the
> pagetable pages.  Once pagetable construction has finished, it would
> switch to the real xen_set_pte, which operates as normal.
>
> This has the downside of making init-time xen_set_pte a little strange,
> but it does have the advantage of making the Xen constraints solely the
> responsibility of the Xen code, and it is mitigated by the fact that it
> is only in effect during pagetable_init.
>
> Would that work for everyone?

For a short term solution it sounds reasonable.

Eric
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/

\
 
 \ /
  Last update: 2007-04-28 08:43    [from the cache]
©2003-2008